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BRITISH STANDARD BS 5422:2001IncorporatingCorrigendum No. 1

Method for specifyingthermal insulating

materials for pipes,

tanks, vessels,

ductwork and

equipment operating

within the temperature

range 40 C to +700 C

ICS 23.040.01; 27.220

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BS 5422:2001

This British Standard, havingbeen prepared under thedirection of the EngineeringSector Policy and StrategyCommittee, was publishedunder the authority of theStandards Policy and StrategyCommittee on05 December 2001

BSI 13 November 2002

First published July 1977

Second edition July 1990

Third edition December 2001

The following BSI referencesrelate to the work on thisBritish Standard:

Committee reference RHE/9

Draft for comment 01/706326 DC

ISBN 0 580 38645 7

Committees responsible for thisBritish Standard

The preparation of this British Standard was entrusted to TechnicalCommittee RHE/9, Thermal insulating materials, upon which the following

bodies were represented:

Association of Building Component Manufacturers

Autoclaved Aerated Concrete Products

BEAMA Ltd. Power Generation Contractors Association

Chartered Institution of Building Services

Concrete Block Association

Cork Industry Federation

Cranfield University

Department of the Environment, Transport and the Regions (represented bythe Building Research Establishment)

Electricity Association

Energy Industries Council

EURISOL UK Mineral Wool Association

European Phenolic Foam Association

Gypsum Products Development Association

National Physical Laboratory

Thermal Insulation Contractors Association

Thermal Insulation Manufacturers and Suppliers Association

Co-opted members

The following bodies were also represented in the drafting of the standard,through subcommittees:

British Refrigeration Association

British Rigid Urethane Foam Manufacturers Association

HEVAC Association

Insulation Jacket Manufacturers Federation

Polyethelene Foam Insulation Association

Amendments issued since publication

Amd. No. Date Comments

13982Corrigendum No. 1

13 November 2002 Changes to Table 19, Table 20, Table 21,Table A.1 and Table C.1

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Contents

Page

Committees responsible Inside front cover

Foreword iii

Introduction 1

1 Scope 1

2 Normative references 1

3 Definitions 2

4 Application of this standard 3

5 General requirements 5

6 Refrigeration applications 8

7 Chilled and cold water applications 16

8 Central heating, air conditioning and direct hot water supplyinstallations in non-domestic applications 18

9 Central heating and hot and cold water services for domestic

applications 2310 Process pipework and equipment applications 24

11 Protection against freezing 36

Annex A (informative) Determination of environmental thickness 41

Annex B (informative) Default values for use in BS EN ISO 12241 heattransfer calculations 43

Annex C (informative) Summary of criteria used to establish the tables 45

Annex D (informative) Outside diameters of steel and copper pipes 46

Annex E (informative) Explanation of Class 0 rating and limitedcombustibility 47

Annex F (normative) Method for assessing the system load for refrigerationpipe-work 48

Annex G (normative) Calculation of economic insulation thickness 50Bibliography 52

Figure 1 Flow chart indicating application of the standard 4

Figure 2 Graph to determine environmental heat gain for intermediatetemperatures 21

Figure A.1 Heat loss related to pipe diameter for non-domestic heatingpipe at 75 C insulated in accordance with Table 12 41

Figure F.1 Example of Mollier diagram for R-22 49

Figure G.1 Economic thickness 50

Table 1 Maximum permitted water vapour permeance in relation to planttemperature at an ambient temperature of +20 C (dry bulb) 8

Table 2 Minimum insulation thickness for refrigeration applications toprevent condensation on a high emissivity outer surface (0.90) with anambient temperature of +20 C and a relative humidity of 70 % 10

Table 3 Minimum insulation thickness for refrigeration applications toprevent condensation on a low emissivity outer surface (0.05) with anambient temperature of +20 C and a relative humidity of 70 % 11

Table 4 Minimum insulation thickness for refrigeration applications toprevent condensation on a high emissivity outer surface (0.90) with anambient temperature of +25 C and a relative humidity of 80 % 12

Table 5 Minimum insulation thickness for refrigeration applications toprevent condensation on a low emissivity outer surface (0.05) with anambient temperature of +25 C and a relative humidity of 80 % 13

Table 6 Environmental insulation thickness for refrigeration applications

to control heat gain 14Table 7 Minimum insulation thickness for chilled and cold water suppliesto prevent condensation on a high emissivity outer surface (0.90) with anambient temperature of +25 C and a relative humidity of 80 % 17

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Table 8 Minimum insulation thickness for chilled and cold water suppliesto prevent condensation on a low emissivity outer surface (0.05) with anambient temperature of +25 C and a relative humidity of 80 % 17

Table 9 Environmental insulation thickness for chilled water supplies tocontrol heat gain 18

Table 10 Minimum insulation thickness for condensation control onductwork carrying chilled air in ambient conditions: indoor still airtemperature +25 C, relative humidity 80 %, dewpoint temperature 21.3 C 20

Table 11 Environmental insulation thickness on ductwork carryingwarm air 21

Table 12 Environmental insulation thickness for non-domestic heatinginstallations to control heat loss 22

Table 13 Environmental insulation thickness for non-domestic hot waterservice areas to control heat loss 23

Table 14 Environmental insulation thickness for domestic central heatinginstallations and hot water systems in potentially unheated areas to controlheat loss 24

Table 15 Environmental insulation thickness for process pipework and

equipment to control heat loss 26Table 16 Insulation thickness for personnel protection from a non-metallicsurface with a surface emissivity of 0.90 and design cold face temperatureof 59 C 28

Table 17 Insulation thickness for personnel protection from a metallicsurface with a surface emissivity of 0.05 and design cold face temperatureof 50 C 30

Table 18 Insulation thickness for personnel protection from a non-metallicsurface with a surface emissivity of 0.90 and design cold face temperatureof 50 C 32

Table 19 Heat loss from bare surfaces calculated in accordance withBS EN ISO 12241 (black steel pipes) 34

Table 20 Heat loss from bare surfaces calculated in accordance withBS EN ISO 12241 (copper pipes commercial grade, scoured to a shine) 35

Table 21 Heat loss from bare surfaces calculated in accordance withBS EN ISO 12241 (copper pipes oxidized) 36

Table 22 Minimum insulation thickness to protect steel pipes againstfreezing under selected industrial process conditions 37

Table 23 Minimum insulation thickness required to give protectionagainst freezing under specified commercial and institutional conditions 38

Table 24 Minimum insulation thickness to protect against freezing fordomestic cold water systems (12 h) 39

Table 25 Minimum insulation thickness to protect against freezing fordomestic cold water systems (8 h) 40

Table A.1 Environmental thickness methodologies 42

Table B.1 Surface emissivity () 43

Table B.2 Default data for use in BS EN ISO 12241 calculations 44

Table C.1 Summary of criteria used to establish the tables 45

Table D.1 Outside diameter of steel pipe (from BS 3600) 46

Table D.2 Outside diameter of copper pipe (from BS EN 1057) 46

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BSI 13 November 2002 iii

Foreword

This British Standard has been prepared by Technical Committee RHE/9,Thermal insulating materials. It supersedes BS 5422:1990, which is withdrawn.

The methods of calculation used in this standard have been revised to harmonize

with the methods in BS EN ISO 12241, which were developed to give uniforminternational methods of calculation, and differ slightly from those given in theprevious edition of BS 5422.

All tables of insulation thicknesses have been reviewed. The assumptions onwhich the tables are based are given in each case.

The previous economic insulation thicknesses have been revised in the contextof their potential to limit carbon dioxide (CO2) emissions, whilst maintaining dueconsideration of both economic and practical factors. This new approach isreferred to as the environmental thickness calculation.Annex Ashows the wayin which the environmental thickness was derived from the economic thickness.

The frost protection tables have been revised to reflect more accurately UK designand operating conditions.

The standard is not prescriptive, and recognizes that there are many reasons whythe insulation of pipes, tanks, vessels, ductwork and equipment may be required.It is therefore important that specifiers state the criteria or specific clause orreference in this standard in any specification.

Insulation thicknesses are given for a range of thermal conductivities appropriateto the usual materials used for the application; thicknesses for intermediatethermal conductivities and pipe sizes may be deduced by calculation orinterpolation. For assistance in selecting an appropriate type of insulation andsuitable methods of application, reference should be made to BS 5970.

Unless otherwise stated, the temperature of the surface to be insulated is takento be the temperature of the fluid inside the pipe, tank, duct, vessel or other pieceof equipment.

NOTE Requirements in this standard are expressed in accordance with BS 0-3:1997, 10.1.3.1.1,which states, Requirements shall be expressed using wording such as: When tested as described inannex A, the product shall ... . This means that only those products that are capable of passing thespecified test will be deemed to conform to this standard.

Annex FandAnnex Gare normative.Annex A,Annex B,Annex C,Annex DandAnnex Eare informative.

This publication does not purport to include all the necessary provisions of aontract. Users are responsible for its correct application.

Compliance with a British Standard does not of itself confer immunityfrom legal obligations.

Summary of pages

This document comprises a front cover, an inside front cover, pages i to iv,pages 1 to 53 and a back cover.

The BSI copyright notice displayed in this document indicates when thedocument was last issued.

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Introduction

In any single application, thermal insulation material can perform a variety of functions simultaneously,including:

a) inhibit freezing in an unheated pipe;

b) prevent condensation on a chilled or cold pipe;

c) protect personnel from exposure to extremes of temperature;

d) conserve energy for both cooled and heated systems;

e) control process temperatures.

Even within the range listed, consideration should be given to sub-sectors of these functions.

For example, energy conservation can be driven by two distinct considerations. The first, and moretraditional, reason for seeking energy saving is to save cost. The second, and more recent, reason forseeking energy saving is to minimize carbon dioxide emissions from the associated power source. Although

any insulation measure has desired effects in both of these areas simultaneously, the extent of insulationthat can be justified varies with the comparative costs of energy on the one hand, and alternative costs ofcarbon dioxide emission abatement on the other. Since thermal insulation of pipework and equipmentrepresents one of the most cost-effective ways available of limiting carbon dioxide emissions, this standardhighlights a series of environmental thicknesses within its core tables. (The derivation of these thicknessesfrom the previous edition of BS 5422 is explained inAnnex A.) Nonetheless, it is still possible, and fullyjustified, to choose an economic insulation thickness where carbon dioxide emissions are of lowerimportance (e.g. with low carbon fuels) and cost minimization is the priority.

Although the tables provided in this standard offer a simple method of determining the minimum thicknesslevels, their use will require the basic information outlined in clause 4and, in some cases, additionalinformation may be required. This specific information is outlined in the clauses pertaining to specificapplications.

It is also common that information such as the thermal conductivity of the chosen insulation material orthe pipe diameter do not conform to the categories highlighted in the relevant tables. Under thesecircumstances, it is possible to interpolate between either columns or rows where the margin of error is notlikely to be critical. For situations where the application parameters differ from those covered within thescope of a table (e.g. different ambient air temperature), the specifier will need to revert to first principlesby using methods set out in BS EN ISO 12241.

The default values for use in BS EN ISO 12241 heat transfer calculations are given inAnnex B, the criteriaused to establish the tables are summarized inAnnex C, and the diameters of pipes considered are giveninAnnex D.

1 Scope

This British Standard describes a method for specifying requirements for thermal insulating materials onpipes, tanks, vessels, ductwork and equipment for certain defined applications and conditions within the

temperature range 40 C to +700 C. It also specifies physical requirements for the insulating materials.It is intended for use by specifiers, contractors and manufacturers of thermal insulation.

This British Standard does not apply to pipelines that are embedded underground, nor does it refer to theinsulation of building construction.

2 Normative references

The following normative documents contain provisions which, through reference in this text, constituteprovisions of this British Standard. For dated references, subsequent amendments to, or revisions of, anyof these publications do not apply. For undated references, the latest edition of the publication referred toapplies.

BS 476-6:1989, Fire tests on building materials and structures Part 6: Method of test for fire propagationfor products.

BS 476-7:1997, Fire tests on building materials and structures Part 7: Method of test to determine theclassification of the surface spread of flame of products.

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BS 476-12:1991, Fire tests on building materials and structures Part 12: Method of test for ignitability ofproducts by direct flame impingement.

BS 3177, Method for determining the permeability to water vapour of flexible sheet materials used forpackaging.

BS 4370-2:1993, Methods of test for rigid cellular materials Part 2: Methods 6 to 10.

BS 5970: 2001, Code of practice for thermal insulation of pipework and equipment (in the temperaturerange 100C to +870C).

BS EN ISO 12241:1998, Thermal insulation for building equipment and industrial installations Calculation rules.

ISO 1182, Fire tests Building materials Non-combustibility tests.

3 Definitions

For the purposes of this British Standard, the following definitions apply.

3.1

assumed lifetime

lifetime assumed for insulation installed in a defined application

NOTE This is used to provide an assessment of the amount of energy (and hence carbon dioxide) saved by the use of the insulation.

3.2

chilled water

water that has been processed through cooling plant (typically 0 C to +10 C)

3.3

cold water

water delivered from the mains or natural supply

3.4economic thickness

thickness of insulation that minimizes the total cost (investment and running costs) over a chosenevaluation period (usually significantly less than the assumed lifetime)

3.5

environmental thickness

thickness of insulation that delivers energy saving at an investment level commensurate with othermeasures to save carbon dioxide (CO2) and offers parallel performance to other insulation materialsselected to the same criteria

3.6

evaluation period

time over which the heat transfer through insulated surfaces is to be calculated, e.g. to carry out frost

protection or economic thickness calculations

3.7

finishing materials

materials used to cover the insulation, whether pre-applied or applied on site

3.8

insulation thickness

thickness of insulating material, excluding any finish or covering

3.9

pre-applied

applied to the insulation prior to delivery to the point of use

3.10termination point

point at which the thermal insulation applied to a pipe, duct or vessel is terminated, e.g. at a valve orflange, or where traversing a wall or ceiling

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3.11

vapour barrier

water-vapour-retarding layerNOTE Permeance values for vapour barriers are given in Table 1.

4 Application of this standard

A specification produced in accordance with this British Standard shall specify only those elements of thestandard to which conformity is required for a specific application. A specification shall be deemed toconform to this British Standard if it makes reference to the clauses and tables within this standard thatpertain to the application being specified. The selection of materials and the insulation thickness to bespecified shall be determined according to the intended function of the insulation (see Figure 1).

The specification shall state the prime purpose of the insulation and shall specify the performancerequirements for the selected insulation system. The specification shall identify the minimum thicknessrequirements for each parameter of performance and shall identify the parameter that requires thegreatest thickness for the application in question.

The performance requirements shall be specified in accordance with the appropriate clauses and tables ofthis standard, which shall be determined from the following factors:

a) system operating temperature;

b) design ambient air temperature;

c) relative humidity of the ambient air;

d) air velocity;

e) location of the plant (indoors or outdoors);

f) pipe diameter (or flat surface dimensions);

g) orientation of pipes (horizontal or vertical);

h) vertical dimensions of flat surfaces;

i) emissivity of outer surface.

For refrigerated, chilled and other cold applications the following performance requirements, if applicable,shall also be specified in accordance with the appropriate clauses and tables of this standard:

j) resistance of the insulation material to the passage of water;

k) permeance of any vapour barriers used.

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Figure 1 Flow chart indicating application of the standard

Select the reasonsfor insulating

Inhibitfreezing

Controlcondensation

Protectpersonnel

Controlprocesses

Conserveenergy

Cost saving(economic)

Carbon saving(environmental)

Clause 6

Clause 7

Clause 8

Tables 2, 3, 4, and 5

Tables 7 and 8

Table 10 (duct)

Clause 9

Clause 10

Clause 11

Tables 16, 17, 18

Table 6

Table 9

Tables 12 and 13

Table 14

Table 15

A and FG

Tables 22, 23, 24, 25

Annex

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5 General requirements

5.1 Physical characteristicsThe manufacturer or specifier shall specify requirements for the physical characteristics of the insulatingmaterial, including finishing materials whether pre-applied or applied on site, to conform to theappropriate British Standard.

Where combustible insulating materials are used, the fire performance shall conform to 6.2.2,7.2.2,8.2.2,9.2.2, or 10.2.2, as appropriate.

The manufacturer or supplier shall specify requirements, together with appropriate methods forverification, for the insulating material to conform to whichever of the following conditions are deemed tobe appropriate.

a) The materials do not contain substances that will support pests or encourage the growth of fungi.

b) The materials are free from objectionable odour at the temperatures at which they are to be used.

NOTE 1 Transient effects during the initial period of use may generally be ignored.

c) The materials do not suffer permanent structural or physical deterioration as a result of contact withmoisture.

d) The insulation is suitable for specified conditions of use without the physical properties falling outsidethe tolerances allowed in the appropriate British Standard for the material.

e) The materials in contact are compatible and do not cause corrosion or degradation under normal siteconditions.

f) The materials and their method of application do not constitute a known risk to health duringapplication or use.

NOTE 2 Reference should be made to BS 5970 for health hazards when selecting, storing or removing insulation. Attention isalso drawn to the latest edition of HSE Guidance Note EH 40 [1].

5.2 Installation requirementsNOTE Guidance on the correct application of insulation and associated attachments is given in BS 5970.

If different forms of insulation are likely to be used for specific areas of the installation, the specifier shallindicate whether or not such areas are to be treated identically or differently.

The specifier shall state the type of finish to be applied if additional protection is required.

5.3 Thermal conductivity

5.3.1 General

Manufacturers of insulating materials shall supply a table of declared thermal conductivity values basedon results of tests carried out in accordance with the appropriate British Standards. The information shallinclude the corresponding cold face temperatures and the product identification. Thermal conductivityshall be expressed in Watts per square metre for 1 m thickness and a temperature difference of 1 K.

NOTE 1 The values for thermal conductivity quoted in the tables relate to the appropriate insulation mean temperature, which isdefined as the mean of the operating temperature of the system added to the temperature of the outer surface of the insulation system.

NOTE 2 In terms of unit symbols thermal conductivity should be expressed as Wm/(m2K) but in normal practice it is simplifiedto W/(mK).

5.3.2 Single-layer insulation (or multilayer insulation where the layers are of the samecomposition)

In all cases the contractor shall state the manufacturers declared values of thermal conductivity for eachmaterial proposed. These declared values shall be appropriate to the mean temperature of the appliedinsulation.

5.3.3 Composite insulation

When two or more layers of dissimilar insulating material are to be used, the contractor shall provide

the declared value of thermal conductivity for each layer under the appropriate temperature conditions.The thickness of each layer shall also be stated.

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5.3.4Design value of thermal conductivity and thermal bridges

Additional allowances shall be made to ensure that the specified performance is achieved where system

inefficiencies are created through the ageing of the product, or by the use of uninsulated valves or otherancillary fittings.

NOTE 1 An appropriate methodology for ensuring compliance is given in BS EN ISO 12241:1998, Annex A.

NOTE 2 To limit heat transfer through supports, load-bearing insulating material should be used on the pipe or vessel between thesupport and the surface to be insulated. If a water vapour barrier is required, the sealing of the load-bearing material should conformto the same requirements as the basic insulation and fitted so that the integrity of the vapour barrier of the system is maintained.Where the heat transfer through the supports does not need to be limited but a water vapour barrier is required, the edges of theinsulation, where interrupted at the support, should be sealed to maintain the effectiveness of the vapour barrier.

NOTE 3 Although it is possible to compensate for uninsulated valves by increasing insulation levels elsewhere, it can prove morecost-effective to insulate the valves themselves using appropriate fittings which should be selected on the basis of ease of access wherenecessary.

5.4 Temperature limitations

The manufacturer shall state the maximum and minimum continuous operating temperatures of theproducts specified, and any other temperature limitation appropriate to the anticipated service conditions.

If the temperature of the surface to be insulated is above the limiting temperature of the preferred maininsulating material, composite or alternative insulation shall be specified. Where composite insulation isspecified, the thickness of each layer shall be calculated to ensure that the interface temperature betweenthe two materials does not exceed the limiting temperature for the material of the outer layer.

5.5 Thickness

If thicknesses are required other than those given in the tables in the appropriate section, or bases otherthan those from which they were derived, the specification shall state the thickness required or the basesto be used in the calculation.

If the thicknesses given in, or interpolated from, the tables do not correspond with available thicknesses,the nearest higher available thickness shall be used.

In multilayer applications, where material thicknesses are rounded up to suit available thicknesses, afurther calculation in accordance with BS EN ISO 12241 shall be made to ensure that each interfacetemperature is below the maximum continuous operating temperature of the materials involved.

NOTE 1 Additional allowances should be made for heat transfer through joints, valves and other fittings when determininginsulation thickness in accordance with BS EN ISO 12241.

NOTE 2 Thicknesses given in the tables within this standard are specifically calculated against the criteria noted in each table.Adopting these thicknesses may not necessarily satisfy other design requirements.

5.6 Fire performance

5.6.1 Different levels of fire performance, the requirements for which are given in 5.6.2, 5.6.3, 5.6.4, 5.6.5,5.6.6, 5.6.7, 5.6.8, 5.6.9, 5.6.10and 5.6.11, shall be specified according to the type of application.The particular requirements to be specified for each type of application shall be selected in accordancewith 6.2.2, 7.2.2, 8.2.2, 9.2.2or 10.2.2.

NOTE In the event of a fire some insulation systems can generate appreciable quantities of smoke and toxic fumes. Considerationshould be given to the choice of materials bearing in mind their location, e.g. enclosed areas or adjacent to air ducts through whichthe smoke or fumes may spread.

5.6.2 When tested in accordance with BS 476-12:1991, insulation materials shall be resistant to ignitionsources types A and B.

5.6.3 When tested in accordance with BS 476-7:1997, the complete assembly of insulation materials, asinstalled, shall conform to the class 1 spread of flame requirements.

5.6.4 Where the insulating material itself (i.e. without any facing) is not rated class 1 when tested inaccordance with BS 476-7:1997, particular care shall be taken with the added facing material to ensurethat all joints and seams, etc. are fitted correctly, so that the underlying insulation is not left exposed anddoes not therefore provide a potential ignition source.

NOTE Where the complete assembly is liable to mechanical damage in use, the final finish should be sufficiently strong to ensurethat the insulation does not become exposed.

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5.6.5 Fire certification for faced materials shall state the nature of the facing material, the type and weightof any reinforcement, the type and weight of adhesive, the type and manufacturer of the substrate and any

other factors pertinent to the fire performance of the system.5.6.6 When tested in accordance with BS 476-7:1997, the insulation material itself (i.e. without any facing)shall conform to the class 1 spread of flame requirements.

5.6.7 When tested in accordance with BS 476-6:1989, the complete insulation assembly as installed, andthe insulation material itself where it is used unfaced, shall achieve a fire propagation index (I) notexceeding 12.0, of which the initial subindex of performance (i1) shall be not more than 6.0.

5.6.8 When tested in accordance with ISO 1182, insulation systems on pipework or ductwork traversing afire-resisting division shall be shown by independent data to maintain the level of fire resistance of thewall, floor or cavity barrier through which they pass.

5.6.9 In underground or windowless buildings, the thermal insulation material used for external insulationof ventilation ductwork or pipes greater than 100 mm nominal bore size, when tested in accordance with

ISO 1182, shall itself be of limited combustibility or non-combustible, with a weight loss during the testof not more than 50 %. In addition, the complete insulation assembly as installed shall conform to theclass 1 spread of flame requirements when tested in accordance with BS 476-7:1997, and the firepropagation requirements when tested in accordance with BS 476-6:1989 (see 5.6.7).

NOTE SeeAnnex Efor an explanation of limited combustibility.

5.6.10 When tested in accordance with ISO 1182, insulation materials for use at temperaturesabove 230 C (excluding finishing materials) shall be of limited combustibility or non-combustible, witha weight loss during the test of not more than 50 %.

NOTE SeeAnnex Efor an explanation of limited combustibility.

5.6.11 If there is a potential hazard from contamination by oil or other flammable chemicals, a suitablyresistant finish, e.g. a metal sheet or appropriate non-absorbent coating, shall be applied over thevulnerable areas. The lapped joints of sheet finishes shall be arranged to shed contaminating fluids away

from the insulating material.

5.7 Vapour barrier Permeance requirements

NOTE 1 Condensation of water vapour will occur on a surface that is at a temperature below the atmospheric dew pointtemperature. Moisture can be deposited within the insulating material and on the insulated metal surface. Where the insulatedsurface is likely to be at or below the dew point temperature during any part of its operating cycle, an effective vapour barrier shouldbe applied on the warmer face of the insulation to avoid deposition of moisture within the insulating system. The presence of waterwithin an insulation system can reduce thermal effectiveness and lead to corrosion of metal components.

For the purpose of this standard an effective vapour barrier shall be deemed to be one that meets the watervapour permeance requirements given in this subclause.

Different levels of water vapour permeance shall be specified according to the type of application. Wherethe insulating material itself does not conform to the water vapour permeance requirement, a vapourbarrier on the outside (warm side) of the insulation shall be used.

The vapour barrier shall take the form of a coating or sheet material. Any joints in the coating or sheetmaterial or in the insulating material itself, where it is providing the water vapour permeancerequirement, shall be fully sealed.

NOTE 2 This is to ensure that the vapour permeance performance is maintained continuously in the system as installed.

Particular care shall be taken at termination points. The external vapour barrier, where required, shall bepre-applied or applied immediately after fitting the insulating material and before the fluid in the pipe,duct, or vessel is cooled.

When a vapour barrier is used, the system as installed, when tested in accordance with the variousmethods specified in 5.6, shall have a fire performance at least equal to that specified in 5.6as appropriateto the type of application.

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The water vapour permeance of a flexible sheet material used as the vapour barrier shall be assessed inaccordance with the method given in BS 3177. The test conditions, e.g. temperate or tropical, and the

thickness of the test specimen shall be stated. Where the apparatus for the method in BS 3177 is unsuitablebecause of the thickness of the test specimen, BS 4370-2:1993, method 8 shall be used. The permeance ofthe vapour barrier shall be selected according to its relationship to the cold surface temperature of the plantand to the temperature difference, in degrees centigrade (C), between the plant temperature and ambienttemperature as indicated in Table 1.

Table 1 Maximum permitted water vapour permeance in relation to plant temperature at anambient temperature of +20 C (dry bulb)

NOTE 3 The permeance values given in Table 1 are applicable at an ambient temperature of 20 C and a relative humidity of 70 %,and other environmental conditions resulting in an equal or lesser partial vapour pressure difference. In order to calculate the partialvapour pressure difference, the internal temperature should be assumed to be equal to the plant temperature and the internal relativehumidity to be 100 %. In situations where the environmental conditions are normally 25 C and a relative humidity of 80 % the vapourbarrier permeance is selected from the table by subtracting 10 C from the plant operating temperature.

Where an external vapour barrier is used in service, separate layers in the form of coatings or sheetmaterial shall be used for the individual purposes. The specifier shall state the type of finish to be appliedwhere additional protection is required. Where such additional protection is specified, the installer shall

ensure that its application does not cause any damage to the vapour barrier during its installation and isunlikely to cause damage in service. (For further details see BS 5970:2001.)

NOTE 4 The use of an external vapour barrier where specified is an essential requirement for the proper functioning of theinsulation system. It is essential that its use for this purpose is not compromised by its additional use for other purposes e.g. as a formof weather protection or as mechanical protection for the thermal insulation.

5.8 Tests on physical properties

Where particular physical properties are required the specifier shall nominate the appropriate BritishStandard test methods. Only where no suitable British Standard test methods exist shall the specifierauthorize the use of an alternative test method to determine whether the required level of performance ismet.

6 Refrigeration applications

6.1 Information to be supplied by the specifier

The specifier shall supply details of the intended function and performance requirements of the application,and the materials to be used, in accordance with clause 4.

NOTE In addition to the parameters outlined in clause 4,items such as specific heat capacity and mass flow rates of fluids may alsobe required under certain circumstances, particularly where calculating from first principles using BS EN ISO 12241. However, theseadditional parameters are not required for the use of the tables contained in this standard.

6.2 Physical characteristics

6.2.1 General

The physical characteristics of the insulating material including finishing materials and vapour barriers,whether applied during manufacture or on site, shall conform to 5.1, 6.2.2and 6.2.3.

Temperature of plant (cold surface)C

Water vapour permeance of barrierg/(sMN)

10 0.050

5 0.015

0 0.010

5 0.004

10 0.002

15 0.0015

20 to 40 0.0010

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6.2.2 Fire performance

Insulation materials and systems used for refrigeration shall conform to 5.6.2, 5.6.3, 5.6.5, 5.6.8and 5.6.9.

Insulation materials and systems used for refrigeration shall also conform to 5.6.4except where theinstalled insulation assembly is unfaced, when 5.6.6shall apply.

Where the equipment and pipework is located in non-domestic buildings, but excluding processapplications, the insulation system shall conform to 5.6.7.

6.2.3 Water vapour barrier Permeance requirements

Insulation materials and systems used for refrigeration shall be installed in accordance with and shallconform to the permeance requirements specified in 5.7.

When tested in accordance with BS 3177 or BS 4370-2, as appropriate, the permeance of the material usedas a vapour barrier shall not exceed the values given in Table 1for the appropriate temperature of theplant.

6.3 Insulation thickness

6.3.1Protection against condensation

In the absence of specific instructions from the specifier, the insulation thickness shall be not less than thatgiven in Table 2, Table 3, Table 4and Table 5, as appropriate.

6.3.2 Insulating to minimize heat gain

NOTE Under certain circumstances, typically where heat gain from distribution pipes represents greater than 5 % of the totalsystem refrigeration load, it may be appropriate to consider insulating to minimize heat gain. This can require greater thicknessesthan those required for condensation control.

If insulation is used to minimize heat gain, the insulation thickness shall be not less than that givenin Table 6 for the temperature range 0 C to 40 C.

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Table 2 Minimum insulation thickness for refrigeration applications to prevent condensation on a surface (0.90) with an ambient temperature of +20 C and a relative humidity of 70

Outside diameter ofsteel pipe on whichinsulation thickness

has been based(mm)

Insulation thickness(mm)

t= 0 t= 10 t= 20 t= 30

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.05

21.3 5 7 9 11 8 11 14 16 10 14 18 22 13 18 22 27

33.7 5 8 10 12 8 12 15 18 11 16 20 24 14 20 25 30

60.3 6 8 11 13 9 13 17 21 13 18 23 28 16 22 29 34114.3 6 9 12 15 10 15 19 24 14 20 26 32 18 25 33 40

168.3 7 10 13 16 11 16 21 25 15 22 28 34 19 27 35 43

273.0 7 10 13 17 12 17 22 27 16 23 30 37 20 29 38 47

508.0 7 11 14 18 12 18 24 29 17 25 33 40 22 32 41 51

610.0 8 11 15 18 12 18 24 30 17 25 33 41 22 32 42 52

Flat surfaces 8 11 15 18 12 18 24 30 17 26 34 43 22 33 44 55

Key

t = temperature of contents (C)

= thermal conductivity at mean temperature of insulation [W/(mK)]

NOTE Thicknesses given are calculated specifically against the criteria noted in the table. These thicknesses may not satisfy other design requir

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has been based

(mm)


t= 0 t= 10 t= 20 t= 30

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.05

21.3 9 13 16 20 14 20 26 31 19 27 35 42 24 34 44 53

33.7 10 14 19 23 16 23 30 36 22 31 40 49 27 39 50 61

60.3 12 17 22 27 19 27 35 43 26 37 48 59 33 47 60 73

114.3 14 20 27 33 23 33 43 52 31 45 58 71 39 57 73 89

168.3 16 23 30 36 25 37 48 59 35 50 65 80 44 64 82 101

273.0 17 26 34 41 29 42 55 67 40 58 75 92 50 73 95 116

508.0 20 30 39 49 33 49 65 80 46 68 89 110 59 87 113 139

610.0 21 31 41 51 35 52 68 84 49 71 94 115 62 91 119 146

Flat surfaces 20 30 40 50 34 51 68 85 48 72 96 119 62 93 123 154

Keyt= temperature of contents (C)




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has been based(mm)


t= 0 t= 10 t= 20 t= 30

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.05

21.3 10 14 17 21 13 19 24 28 17 23 29 35 20 28 35 42

33.7 11 15 19 23 15 21 26 32 19 26 33 40 22 31 39 47

60.3 12 17 22 26 17 24 30 36 21 30 38 46 26 36 45 55114.3 13 19 25 30 19 27 34 42 24 34 44 53 29 41 53 63

168.3 14 20 26 32 20 29 37 45 26 37 47 57 31 44 57 69

273.0 15 22 28 35 21 31 40 49 27 40 51 63 33 48 62 76

508.0 16 23 30 37 23 33 44 54 29 43 56 69 36 53 69 84

610.0 16 24 31 38 23 34 44 55 30 44 58 71 37 54 70 86

Flat surfaces 16 24 32 39 23 35 46 58 31 46 61 76 38 57 76 94

Key

t= temperature of contents (C)




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has been based

(mm)


t= 0 t= 10 t= 20 t= 30

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.05

21.3 19 28 36 43 27 39 50 61 35 50 64 79 42 60 78 96

33.7 22 32 41 50 31 45 58 70 40 57 74 90 48 69 90 109

60.3 27 38 49 60 37 53 69 84 48 68 88 107 58 83 107 130

114.3 32 46 60 73 45 65 84 102 58 83 107 131 70 101 130 158

168.3 36 51 67 82 51 73 94 115 65 93 121 147 79 113 146 178

273.0 40 59 77 94 58 84 109 133 75 108 140 170 91 131 169 206

508.0 47 69 91 112 68 99 130 159 88 128 167 205 108 157 203 249

610.0 49 73 95 117 71 104 136 167 93 135 176 216 113 165 214 262

Flat surfaces 49 73 97 122 72 107 143 179 95 142 189 236 117 176 234 292

Keyt= temperature of contents (C)




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Table 6 Environmental insulation thickness for refrigeration applications to control h

Outsidediameter of

steel pipe onwhich

insulationthickness has

been based(mm)

t= 0 t= 10

Insulation thickness (mm) Heatgain(W/m)

Insulation thickness (mm) Heatgain(W/m)

Insulation

=0.020

=0.025

=0.030

=0.035

=0.040

=0.045

=0.050

=0.020

=0.025

=0.030

=0.035

=0.040

=0.045

=0.050

=0.020

=0.025

=0.030

21.3 12 17 23 32 43 57 76 3.4 15 22 32 44 61 84 114 4.2 19 28 40

33.7 15 21 29 38 50 64 82 4.0 19 28 39 52 70 92 120 4.9 24 35 50

60.3 21 28 37 48 61 76 94 5.0 27 37 50 66 85 108 136 6.0 34 48 66

114.3 29 39 50 63 77 93 112 6.5 39 53 69 88 111 136 162 7.5 47 64 85

168.3 34 45 57 71 85 102 120 7.9 45 61 78 97 120 145 174 9.1 55 74 96

273.0 39 51 64 78 93 109 127 10.6 53 69 88 108 130 154 180 12.0 65 86 109

508.0 45 57 71 84 99 114 131 16.5 62 80 99 119 141 164 189 18.0 78 101 126

610.0 andabove,includingflat surfaces

52 67 82 98 115 132 151 17.2 71 91 113 136 161 187 214 18.9 87 113 141

Key



NOTE 1 Heat gain is related to the specific insulation thickness.

NOTE 2 This table should be used only if the control of heat gain already provided by the insulation of refrigeration pipework for the purposes oindicated in Table 2, Table 3, Table 4and Table 5 does not limit the distribution heat gain to a maximum of 5 % of the system load. The method forrefrigeration pipework is given inAnnex F. Distribution pipework heat gains should be calculated using the formulae given in BS EN ISO 12241 i


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Table 6 Environmental insulation thickness for refrigeration applications to control heat ga

Outsidediameter of

steel pipe onwhich

insulation

thickness hasbeen based(mm)

t= 30 t= 40

Insulation thickness (mm) Heatgain

(W/m)

Insulation thickness (m

=0.020

=0.025

=0.030

=0.035

=0.040

=0.045

=0.050

=0.020

=0.025

=0.030

=0.035

=0.04

21.3 22 33 48 69 99 141 198 5.6 24 36 54 80 116

33.7 28 41 59 82 113 154 210 6.4 32 48 70 100 140

60.3 40 57 79 107 143 188 247 7.5 44 63 89 121 163

114.3 53 73 98 128 163 205 257 9.7 59 82 111 146 188

168.3 63 86 113 144 180 223 273 11.4 70 96 126 162 205

273.0 75 100 128 160 196 237 283 14.6 85 114 147 185 228

508.0 91 119 149 182 218 257 300 20.9 104 136 172 211 254


101 131 164 200 238 280 325 22.5 114 149 188 230 275

Key



NOTE 1 Heat gain is related to the specific insulation thickness.

NOTE 2 This table should be used only if the control of heat gain already provided by the insulation of refrigeration pipework for the purposes of cin Table 2, Table 3, Table 4and Table 5 does not limit the distribution heat gain to a maximum of 5 % of the system load. The method for calculatrefrigeration pipework is given inAnnex F. Distribution pipework heat gains should be calculated using the formulae given in BS EN ISO 12241 i


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7 Chilled and cold water applications

7.1 Information to be supplied by the specifierThe specifier shall supply details of the intended function and performance requirements of the application,and the materials to be used, in accordance with clause 4.

NOTE In addition to the parameters outlined in clause 4, items such as specific heat capacity and mass flow rates of fluids may alsobe required under certain circumstances, particularly where calculating from first principles using BS EN ISO 12241. However, theseadditional parameters are not required for the use of the tables contained in this standard.


7.2.1 General

The physical characteristics of the insulating material, including fixing and finishing materials whetherpre-applied or applied on site, shall conform to 5.1, 7.2.2and 7.2.3.


Insulation materials and systems used for chilled and cold water applications shall conform to 5.6.2, 5.6.3,5.6.5, 5.6.6, 5.6.7, 5.6.8and 5.6.9.


Insulation materials and systems used for chilled and cold water applications shall be installed inaccordance with and shall conform to the permeance requirements specified in 5.7.

When tested in accordance with BS 3177 or BS 4370-2, as appropriate, the permeance of the material usedas a vapour barrier shall not exceed the values given in Table 1for the relevant temperature of the plant.


7.3.1Protection against condensation

In the absence of specific instructions from the specifier, the insulation thickness shall be not less than that

given in Table 7or Table 8as appropriate.

7.3.2 Insulating to minimize heat gain to chilled water pipes

NOTE 1 Under certain circumstances, typically where the heat gain of the distribution network represents more than 5 % of thedesign chiller load, it may be appropriate to consider insulating to minimize heat gain. This can require greater thicknesses than thoserequired for condensation control.

If insulation is specified to minimize heat gain, the insulation thickness shall be not less than that specifiedin Table 9for pipes carrying fluids at 5 C or lower. Where fluid temperatures exceed 5 C in any part of achilled water system, the thicknesses required for 5 C shall be maintained.

Table 9shall be used only if the control of heat gain already provided by the insulation of chilled pipeworkfor the purposes of condensation control as indicated in Table 7and Table 8 does not limit the distributionheat gain to a maximum of 5 % of the system load, which shall be calculated in accordance withAnnex F.

NOTE 2 Distribution pipework heat gains should be calculated using the formulae given in BS EN ISO 12241 if the values areoutside the scope ofTable 9.

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Table 7 Minimum insulation thickness for chilled and cold water supplies to preventcondensation on a high emissivity outer surface (0.90) with an ambient temperature of +25 C

and a relative humidity of 80 %

Table 8 Minimum insulation thickness for chilled and cold water supplies to preventcondensation on a low emissivity outer surface (0.05) with an ambient temperature of +25 C

and a relative humidity of 80 %


has been based(mm)

t= +10 t= +5 t= 0

Insulation thickness (mm) Insulation thickness (mm) Insulation thickness (mm)

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

21.3 6 8 10 12 8 11 14 17 10 14 17 21

33.7 6 9 11 14 9 12 15 19 11 15 19 23

60.3 7 10 13 15 10 14 17 21 12 17 22 26

114.3 8 11 14 17 10 15 19 24 13 19 25 30

168.3 8 11 15 18 11 16 21 25 14 20 26 32

273.0 8 12 16 19 12 17 22 27 15 22 28 35

508.0 9 13 17 21 12 18 24 29 16 23 30 37

610.0 9 13 17 21 12 18 24 30 16 24 31 38

Flat surfaces 9 13 17 21 12 18 24 30 16 24 32 39

Key



NOTE Thicknesses given are calculated specifically against the criteria noted in the table. These thicknesses may not satisfyother design requirements.


has been based(mm)

t= +10 t= +5 t= 0

Insulation thickness (mm) Insulation thickness (mm) Insulation thickness (mm)

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

21.3 11 16 20 25 15 22 28 34 19 28 36 43

33.7 13 18 24 29 18 25 32 39 22 32 41 50

60.3 15 22 28 34 21 30 39 47 27 38 49 60

114.3 18 26 34 41 25 36 47 57 32 46 60 73

168.3 20 29 38 46 28 40 52 64 36 51 67 82

273.0 22 33 43 53 31 46 60 74 40 59 77 94

508.0 26 38 50 62 37 54 71 87 47 69 91 112

610.0 27 40 52 65 38 56 74 91 49 73 95 117

Flat surfaces 26 39 52 65 38 56 75 93 49 73 97 122

Key



NOTE Thicknesses given are calculated specifically against the criteria noted in the table. These thicknesses may not satisfyother design requirements.

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Table 9 Environmental insulation thickness for chilled water supplies to control heat gain

8 Central heating, air conditioning and direct hot water supply installations innon-domestic applications





8.2.1 General

The physical characteristics of the insulating material, together with adhesive, fixing, vapour barrier andfinishing material, whether pre-applied or applied on site, shall conform to 5.1, 8.2.2and 8.2.3.


Insulation materials and systems used for central heating, air conditioning and direct hot water supplyinstallations in non-domestic applications shall conform to 5.6.2, 5.6.3, 5.6.5, 5.6.7, 5.6.8, 5.6.9and 5.6.11.Insulation materials and systems used for central heating, air conditioning and direct hot water supplyinstallations in non-domestic applications shall also conform to 5.6.4except where the installed insulationassembly is unfaced, when 5.6.6shall apply.


If pipework or ductwork for central heating, air conditioning or direct hot water supply systems is likely tohave a surface temperature below the dew point temperature, the insulation materials and system shallconform to the permeance requirements and installation methods for water vapour barriers detailed in 5.7.

Outside diameter of

steel pipe on whichinsulation thickness

has been based(mm)

t= +5 t= 0

Insulation thickness(mm) Heatgain

(W/m)

Insulation thickness (mm) Heatgain(W/m) =

0.020 =

0.025 =

0.030 =

0.035 =

0.040 =

0.020 =

0.025 =

0.030 =

0.035 =

0.040

21.3 10 14 20 27 36 2.9 12 17 23 32 43 3.4

33.7 13 18 24 31 40 3.5 15 21 29 38 50 4.0

60.3 17 23 30 38 47 4.5 21 28 37 48 61 5.0

114.3 23 30 38 47 58 6.1 29 39 50 63 77 6.5

168.3 28 37 46 57 69 7.2 34 45 57 71 85 7.9

273.0 32 41 51 62 72 9.9 39 51 64 78 93 10.6

508.0 35 45 55 66 77 15.8 45 57 71 84 99 16.5

610.0 and above,including flatsurfaces

42 54 66 78 91 16.2 52 67 82 98 115 17.2

Key



NOTE 1 Thicknesses given are calculated specifically against the criteria noted in the table. These thicknesses may not satisfyother design requirements.

NOTE 2 Some thicknesses in this table are less than those in Table 8.

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Insulation materials and systems used for chilled air ductwork shall be installed in accordance with andshall conform to the permeance requirements specified in 5.7.

When tested in accordance with BS 3177 or BS 4370-2, as appropriate, the permeance of the material usedas a vapour barrier shall not exceed the values given in Table 1for the appropriate temperature of theplant.


8.3.1Minimum insulation thickness to prevent condensation on ductwork carrying chilled air

In the absence of specific instructions from the specifier, the insulation thickness shall be not less than thatgiven in Table 10.

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Table 10 Minimum insulation thickness for condensation control on ductwork carrying chilled air iindoor still air temperature +25 C, relative humidity 80 %, dewpoint temperature 21

Minimum airtemperatureinside duct

(C)

Minimum thickness of insulating material(mm)

= 0.020 = 0.025 = 0.030 = 0.035 = 0.040 = 0.0=

0.05=

0.44=

0.90=

0.05=

0.44=

0.90=

0.05=

0.44=

0.90=

0.05=

0.44=

0.90=

0.05=

0.44=

0.90=

0.05=

0.44

15 15 8 5 18 9 6 22 11 7 25 13 8 29 15 10 32 17

10 26 10 9 32 17 11 39 20 13 45 23 15 52 26 17 58 29

5 37 19 12 47 24 15 56 28 18 64 33 21 75 38 24 83 420 48 25 16 60 31 20 72 37 24 84 43 27 96 49 31 108 56

Key

= thermal conductivity of insulating material at a mean temperature of 10 C [W/(mK)]

= external surface emissivity

NOTE 1 Thicknesses calculated in accordance with BS EN ISO 12241 based on 0.6 m vertical flat surface of rectangular duct but are also adequ

NOTE 2 Thicknesses given are calculated specifically against the criteria noted in the table. These thicknesses may not satisfy other design requ

NOTE 3 Refer toAnnex B, Table B.1 for surface emissivities of common finishing materials.


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8.3.2 Environmental insulation thickness for ductwork carrying warm air

In the absence of specific instructions from the specifier, the thickness applied shall be not less than that

given in Table 11and Figure 2.

Table 11 Environmental insulation thickness on ductwork carrying warm air

8.3.3Determination of environmental thickness

NOTE The relevant thicknesses defined in Table 12and Table 13 have been derived using the methodology set out inAnnex A.

In the absence of specific instructions from the specifier, the insulation thickness shall be as given inTable 12, Table 13or Table 14.

Environmental insulation thickness and corresponding heat loss(see Note 2)

Temperature difference = 10 C Temperature difference = 25 C Temperature difference = 50 C

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

=0.020

=0.030

=0.040

=0.050

19 mm 29 mm 38 mm 47 mm 25 mm 38 mm 50 mm 63 mm 32 mm 47 mm 63 mm 79 mm

7.2 W/m2 15.3 W/m2 26.0 W/m2

Key

Temperature difference = difference between air inside ductwork and ambient air

= thermal conductivity at mean temperature of insulating material [W/(m

K)]

NOTE 1 Equivalent environmental thicknesses and heat loss values calculated in accordance with BS EN ISO 12241 basedon 0.6 m depth of vertical flat surface of rectangular duct but are also adequate for horizontal surfaces.

NOTE 2 Heat loss values shown in the table are based on insulation with a low emissivity finish (0.05), in ambient still airat 10 C.

NOTE 3 For intermediate temperature differences, the insulation thickness can be derived by interpolation, or calculated fromfirst principles such that the heat loss given in Figure 2 is not exceeded.

Figure 2 Graph to determine environmental heat gain for intermediate temperatures

0

5

10

15

20

25

30

0 10 20 30 40 50 60

Temperature difference, C

Heatloss,

W/m2

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Table 12 Environmental insulation thickness for non-domestic heating installations to cont

Outsidediameter of

steel pipe onwhich

insulationthickness has

been based(mm)

t= 75 t= 100

Insulation thickness (mm) Heatloss

(W/m)

Insulation thickness (mm) Heatloss

(W/m)

Insulation

=0.025

=0.030

=0.035

=0.040

=0.045

=0.050

=0.055

=0.025

=0.030

=0.035

=0.040

=0.045

=0.050

=0.055

=0.025

=0.030

=0.035

17.2 13 18 24 32 43 55 71 7.7 14 20 27 36 48 62 81 10.8 16 23 32

21.3 14 19 26 34 44 56 72 8.4 15 21 29 38 50 64 81 11.7 18 26 35

26.9 16 21 28 36 46 57 72 9.2 17 23 31 40 52 65 82 12.9 21 28 38

33.7 17 23 30 38 47 58 72 10.1 19 26 33 43 54 68 84 14.0 23 31 41

42.4 19 24 31 39 49 59 72 11.4 21 28 36 45 56 69 84 15.5 25 33 44

48.3 19 25 32 40 49 60 72 12.1 22 29 37 47 58 70 85 16.4 26 35 45

60.3 21 27 34 42 51 61 72 13.5 24 31 39 49 60 72 86 18.3 28 37 48

76.1 22 29 36 43 52 62 72 15.5 26 33 42 51 62 74 87 20.7 31 40 51

88.9 23 30 37 44 53 62 73 17.0 27 35 43 52 63 75 88 22.6 33 42 53

114.3 25 31 38 46 54 63 73 19.7 29 37 45 54 64 76 88 26.2 35 45 56

139.7 26 32 39 47 55 64 73 22.5 30 38 47 56 66 76 88 29.6 37 47 58

168.3 27 33 40 48 56 64 73 25.5 32 40 48 57 67 77 89 33.5 39 50 61

219.1 28 35 42 49 57 65 73 30.9 34 42 50 59 69 79 90 40.0 42 53 64273.0 29 36 43 50 58 66 74 36.3 35 43 52 61 70 80 91 46.6 44 55 66


32 39 46 54 63 71 80 39.6 38 47 56 65 76 87 98 50.9 47 57 69

Key

t= hot face temperature (C)


NOTE Heat loss relates to the specified thickness and temperature.


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Table 13 Environmental insulation thickness for non-domestic hot water service areas tocontrol heat loss

9 Central heating and hot and cold water services for domestic applications





9.2.1 General

The physical characteristics of the insulating material, together with adhesive, fixing, vapour barrier andfinishing materials, shall conform to 5.1, 9.2.2and 9.2.3.


Insulation materials and systems used for central heating and hot and cold water supply installations fordomestic applications shall conform to 5.6.2, 5.6.3, 5.6.5, 5.6.8and 5.6.9. Insulation materials and systemsused for central heating and hot and cold water supply installations for domestic applications shall alsoconform to 5.6.4except where the installed insulation assembly is unfaced, when 5.6.6shall apply.

Where insulation is used on the exterior of pipework that is exposed within the building, the completeassembly of materials as installed shall have a rating for the surface spread of flame of not less than thatfor the wall or ceiling it traverses.

Outside diameter of steelpipe on which insulationthickness has been based

(mm)

Water temperature of 60 C

Insulation thickness (mm) Heat loss(W/m) =

0.025 =

0.030 =

0.035 =

0.040 =

0.045 =

0.050 =

0.055

17.2 12 17 24 32 41 54 69 5.6

21.3 14 19 25 33 43 55 69 6.1

26.9 15 21 27 35 45 56 70 6.7

33.7 17 22 29 37 46 57 70 7.4

42.4 18 24 30 39 48 58 71 8.2

48.3 19 25 32 40 49 60 72 8.7

60.3 21 27 34 42 51 61 73 9.776.1 23 29 36 44 53 62 73 11.0

88.9 24 30 37 45 54 63 74 12.1

114.3 25 32 39 47 55 64 74 14.0

139.7 27 33 40 48 56 65 75 16.0

168.3 28 35 42 49 58 67 76 18.1

219.1 29 36 43 51 59 68 77 21.6

273.0 31 38 45 53 61 69 78 25.1

323.9 and above,including flat surfaces

32 39 46 54 63 71 81 28.5

Key

= thermal conductivity at mean temperature of insulation [W/(m

K)]

NOTE 1 Heat loss relates to the specified thickness and temperature.

NOTE 2 Thicknesses in this table are based on a greater heat utilization than those for heating installations.

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9.2.3 Vapour barriers Permeance requirements

Insulation materials and systems used for cold water services shall be installed in accordance with and

shall conform to the permeance requirements specified in 5.7.

When tested in accordance with BS 3177 or BS 4370-2, as appropriate, the permeance of the material usedfor the vapour barrier shall not exceed the values given in Table 1depending on the temperature of theplant.

9.3 Thickness

9.3.1 Environmental thickness for central heating and hot water installations

NOTE The requirements for domestic heating and hot water are combined into one table for ease of material handling on site. Inaddition the distinction between heated and unheated areas was removed because of concerns over the validity of the assumption ofcontinuous background heat. The basic methodology and approach is outlined inAnnex A.

In the absence of specific instructions from the specifier, the insulation thickness shall be not less than thatspecified in Table 14.

Table 14 Environmental insulation thickness for domestic central heating installations andhot water systems in potentially unheated areas to control heat loss

10 Process pipework and equipment applications


10.1.1 General

The specifier shall supply details of the intended function and performance requirements of the application,and the materials to be used, in accordance with clause 4, as well as the requirements specified in 10.1.2and 10.1.3.

NOTE 1 For the applications appropriate to this clause, the specifier typically indicates the precise performance requirements ofthe insulation system.

NOTE 2 In addition to the parameters outlined in clause 4, items such as specific heat capacity and mass flow rates of fluids mayalso be required under certain circumstances, particularly where calculating from first principles using BS EN ISO 12241. However,these additional parameters are not required for the use of the tables contained in this standard.

10.1.2 Special service requirements

Reference shall be included in the specification to any difficult or unusual site conditions that influence theselection and/or application of insulating materials, e.g. relevant to transport, access, storage, scaffoldingand weather protection.

Outside diameter ofcopper pipe on which

insulation thickness hasbeen based

(mm)

Insulation thickness (mm) Heat lossat 60 C

Heat lossat 75 C =

0.025 =

0.030 =

0.035 =

0.040 =

0.045

10.0 10 16 22 31 44 6.8 W/m 8.6 W/m

12.0 12 18 26 36 49 7.3 W/m 9.2 W/m

15.0 15 22 31 42 58 7.8 W/m 9.7 W/m

22.0 19 26 35 47 62 8.2 W/m 10.2 W/m

28.0 21 28 38 49 64 9.0 W/m 11.3 W/m

35.0 22 30 39 51 64 10.0 W/m 12.6 W/m

42.0 23 31 41 52 65 11.0 W/m 13.8 W/m

54.0 25 33 42 53 65 12.8 W/m 16.0 W/m

Cylinders 35 42 50 58 67 38.2 W/m2 47.9 W/m2

Key


NOTE 1 Heat loss relates to the specified thickness and temperature.

NOTE 2 Water temperatures considered are 75 C for central heating and 60 C for hot water with an ambient still airtemperature of 1 C.

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10.1.3Basis on which thickness is to be determined

The specifier shall state the basis for selection to be used and provide the relevant information giving due

consideration to safety and environmental requirements.

NOTE See 10.3.


10.2.1 General

The physical characteristics of the insulating material, fixing and finishing materials, whether appliedduring manufacture or on site, shall conform to 5.1, 10.2.2and 10.2.3.


Insulation materials and systems used for process applications shall conform to 5.6.2, 5.6.3, 5.6.5, 5.6.8,5.6.9, 5.6.10and 5.6.11. Insulation materials and systems used for process applications shall also conformto 5.6.4except where the installed insulation assembly is unfaced, when 5.6.6shall apply.


NOTE 1 Process applications can encompass systems running at temperatures throughout the full range of this standard, 40 Cto +700 C, and beyond.

Where a process application has a normal operating temperature below ambient temperature, theinsulation material and systems used for such an application shall be installed in accordance with and shallconform to the permeance requirements for water vapour barriers specified in 5.7.

Where a process application has a normal operating temperature above ambient temperature, and a watervapour barrier is installed, the system shall be installed in accordance with and shall conform to thepermeance requirements specified in 5.7.

NOTE 2 The need to apply a vapour barrier is dependant upon whether such a system can on occasion have a surface temperaturebelow the dew point temperature.

When tested in accordance with BS 3177 or BS 4370-2, as appropriate, the permeance of the material usedas a vapour barrier shall not exceed the values given in Table 1 depending on the temperature of the plant.


10.3.1 Environmental

NOTE The environmental insulation thickness for process conditions has been derived according to the methodology given inAnnex A. However, in this instance, cost effectiveness assessments have taken into account gas prices available to the industrialsector. Recognizing the need to reduce carbon dioxide emissions, particularly in the process sector, the thicknesses given in Table 15are intended to achieve this result by reducing the heat loss.

In the absence of specific instructions from the specifier, the insulation thickness shall be as givenin Table 15.

10.3.2 Economic

Where economic thickness determination is deemed to be the most appropriate approach, it shall becalculated in accordance withAnnex G.

NOTE Environmental thicknesses are preferred where practicable because of their greater contribution to environmental objectivesin this sensitive sector.

10.3.3 Other design criteria

Where the requirements for personal protection are pre-eminent, the insulation thickness shall be as givenin Table 16, Table 17and Table 18.

Where other design criteria are identified, e.g. a specified heat loss (see Table 19, Table 20and Table 21),a specified temperature on the outer surface, or a special condition at the point of delivery, the calculationshall be in accordance with BS EN ISO 12241 (see also BS 5970).

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Table 16 Insulation thickness for personnel protection from a non-metallic surface with a surface emiscold face temperature of 59 C

Outside diameter ofsteel pipe

(mm)

t= 100 t= 200

Insulation thickness (mm) Insulation thickness (mm) Insula

=0.025

=0.035

=0.045

=0.055

=0.035

=0.045

=0.055

=0.065

=0.035

0.

17.2 2 3 3 4 7 9 11 12 12 14

21.3 2 3 4 4 8 10 11 13 12 15

26.9 2 3 4 4 8 10 12 14 13 1633.7 2 3 4 4 9 11 13 15 14 17

42.4 2 3 4 5 9 11 13 15 14 18

48.3 2 3 4 5 9 12 14 16 15 18

60.3 3 3 4 5 10 12 14 17 15 19

76.1 3 3 4 5 10 13 15 17 16 20

88.9 3 3 4 5 10 13 15 18 17 21

101.6 3 4 4 5 11 13 16 18 17 21

114.3 3 4 4 5 11 13 16 19 17 22

139.7 3 4 5 5 11 14 17 19 18 23

168.3 3 4 5 6 11 14 17 20 19 23

219.1 3 4 5 6 12 15 18 21 19 24

244.5 3 4 5 6 12 15 18 21 20 25

273.0 3 4 5 6 12 15 18 21 20 25

323.9 3 4 5 6 12 16 19 22 20 26

355.6 3 4 5 6 12 16 19 22 21 26

406.4 3 4 5 6 13 16 19 23 21 27

457.0 3 4 5 6 13 16 20 23 21 27

508.0 3 4 5 6 13 16 20 23 22 27

610.0 3 4 5 6 13 16 20 23 22 27

Flat surfaces 3 4 5 6 13 17 20 24 22 28

Key

t= hot face temperature at mean temperature (C) (with ambient still air at 20 C)



NOTE 2 To simplify the use of this table, the values shaded have been adjusted to avoid the specification of apparently anomalous results given BS EN ISO 12241, due to the transition from turbulent to laminar flow.


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Table 16 Insulation thickness for personnel protection from a non-metallic surface with a surface emiscold face temperature of 59 C (concluded)

Outside diameterof steel pipe

(mm)

t= 400 t= 500 t= 600

Insulation thickness (mm) Insulation thickness (mm) Insulation thickness (mm) I

=0.045

=0.055

=0.065

=0.075

=0.085

=0.055

=0.065

=0.075

=0.085

=0.095

=0.065

=0.075

=0.085

=0.095

=0.105

=0.065

17.2 19 22 26 29 32 27 32 35 39 43 37 42 46 51 55 43

21.3 20 24 27 30 34 29 33 37 42 46 39 44 49 54 58 45

26.9 21 25 29 32 36 31 35 40 44 48 42 47 52 57 62 48

33.7 22 26 30 34 38 33 38 42 47 51 44 50 55 61 66 51

42.4 24 28 32 36 40 35 40 45 50 55 47 53 59 64 70 54

48.3 24 29 33 37 42 36 41 46 51 56 49 55 61 67 72 56

60.3 26 31 35 40 44 38 44 49 54 60 52 58 64 71 77 59

76.1 27 32 37 42 47 40 46 52 58 63 55 62 68 75 81 63

88.9 28 33 38 43 48 42 48 54 60 66 57 64 71 78 85 66

101.6 29 34 40 45 50 43 49 56 62 68 59 66 74 81 88 68114.3 30 35 41 46 51 44 51 57 64 70 60 68 76 83 90 70

139.7 31 37 42 48 54 46 53 60 67 73 63 71 79 87 95 73

168.3 32 38 44 50 56 48 55 63 70 77 66 74 83 91 99 76

219.1 33 40 46 53 59 50 58 66 74 81 70 79 88 97 105 81

244.5 34 41 47 54 60 51 60 68 75 83 71 81 90 99 108 83

273.0 35 42 48 55 61 52 61 69 77 85 73 83 92 101 111 85

323.9 36 43 50 57 63 54 63 71 80 88 75 85 95 105 115 87

355.6 36 43 51 58 64 55 64 73 81 90 77 87 97 107 117 89

406.4 37 44 52 59 66 56 65 74 83 92 79 89 100 110 117 91

457.0 37 45 53 60 67 57 67 76 85 92 80 89 100 110 117 91

508.0 38 46 53 61 67 58 67 76 85 92 80 89 100 110 117 91

610.0 38 46 53 61 67 58 67 76 85 92 80 89 100 110 120 91

Flat surfaces 40 49 57 66 75 63 74 85 97 108 91 104 118 132 146 107

Key






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Table 17 Insulation thickness for personnel protection from a metallic surface with a surface emissivityface temperature of 50 C


(mm)

t= 100 t= 200


=0.025

=0.035

=0.045

=0.055

=0.035

=0.045

=0.055

=0.065

=0.035

0.

17.2 5 7 8 10 17 21 25 29 27 33

21.3 5 7 9 10 18 23 27 31 28 35

26.9 6 7 9 11 19 24 29 34 31 3833.7 6 8 10 12 21 26 31 36 33 41

42.4 6 8 11 13 22 28 33 39 35 44

48.3 6 9 11 13 23 29 35 40 37 46

60.3 7 9 12 14 25 31 37 43 39 49

76.1 7 10 12 15 27 33 40 46 42 53

88.9 8 10 13 15 28 35 42 49 44 55

101.6 8 11 13 16 29 36 44 51 46 57

114.3 8 11 14 17 30 38 45 52 48 60

139.7 8 11 14 17 32 40 48 56 50 63

168.3 9 12 15 18 33 42 50 59 53 67

219.1 9 13 16 20 36 45 54 63 57 72

244.5 10 13 17 20 37 47 56 65 59 75

273.0 10 14 17 21 38 48 58 68 61 77

323.9 10 14 18 22 40 50 61 71 64 81

355.6 10 14 18 22 41 52 62 73 66 83

406.4 11 15 19 23 42 53 65 75 68 86

457.0 11 15 19 23 43 55 67 78 70 89

508.0 11 16 20 24 45 57 69 80 72 92

610.0 12 16 21 25 45 57 69 80 72 92

Flat surfaces 12 16 21 25 46 59 72 85 76 98

Key






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Table 18 Insulation thickness for personnel protection from a non-metallic surface with a surface emiscold face temperature of 50 C


(mm)

t= 100 t= 200


=0.025

=0.035

=0.045

=0.055

=0.035

=0.045

=0.055

=0.065

=0.035

0.

17.2 3 4 5 6 10 13 15 17 15 19

21.3 3 4 5 6 11 13 16 18 16 20

26.9 3 5 6 7 11 14 16 19 17 2133.7 4 5 6 7 12 15 17 20 18 23

42.4 4 5 6 7 13 15 18 21 19 24

48.3 4 5 6 7 13 16 19 22 20 25

60.3 4 5 6 8 13 17 20 23 21 26

76.1 4 5 7 8 14 18 21 24 22 27

88.9 4 5 7 8 14 18 22 25 23 28

101.6 4 6 7 8 15 18 22 26 23 29

114.3 4 6 7 8 15 19 23 26 24 30

139.7 4 6 7 9 16 20 23 27 25 31

168.3 4 6 7 9 16 20 24 28 26 32

219.1 5 6 8 9 17 21 25 29 27 34

244.5 5 6 8 9 17 21 26 30 27 34

273.0 5 6 8 9 17 22 26 30 28 35

323.9 5 6 8 10 18 22 27 31 28 36

355.6 5 6 8 10 18 22 27 32 29 36

406.4 5 6 8 10 18 23 28 32 29 37

457.0 5 7 8 10 18 23 28 33 30 37

508.0 5 7 8 10 19 23 28 33 30 38

610.0 5 7 8 10 19 24 29 34 31 39

Flat surfaces 5 7 8 10 19 24 29 35 31 40

Key






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Table 18 Insulation thickness for personnel protection from a non-metallic surface with a surface emiscold face temperature of 50 C (concluded)

Outside diameterof steel pipe

(mm)

t= 400 t= 500 t= 600

Insulation thickness (mm) Insulation thickness (mm) Insulation thickness (mm) I

=0.045

=0.055

=0.065

=0.075

=0.085

=0.055

=0.065

=0.075

=0.085

=0.095

=0.065

=0.075

=0.085

=0.095

=0.105

=0.065

17.2 25 29 34 38 42 36 42 47 52 57 49 55 61 67 73 56

21.3 26 31 36 40 45 38 44 49 55 60 52 58 65 71 77 59

26.9 28 33 38 43 47 41 47 53 58 64 55 62 69 75 82 63

33.7 30 35 40 45 50 43 50 56 62 68 58 66 73 80 87 67

42.4 32 37 43 48 53 46 53 59 66 72 62 70 77 85 92 71

48.3 33 39 44 50 55 47 54 61 68 74 64 72 80 88 95 74

60.3 34 41 47 53 58 50 58 65 72 79 68 76 85 93 101 78

76.1 36 43 50 56 62 53 61 69 76 84 72 81 90 99 107 83

88.9 38 45 51 58 64 55 63 72 79 87 75 84 94 103 111 86

101.6 39 46 53 60 67 57 66 74 82 90 78 87 97 106 115 89114.3 40 47 55 62 68 59 67 76 84 93 80 90 100 109 119 92

139.7 42 49 57 64 72 61 71 80 89 97 84 94 105 115 125 96

168.3 43 51 59 67 75 64 74 83 93 102 87 99 110 120 131 101

219.1 45 54 63 71 79 68 78 88 98 108 93 105 117 128 139 107

244.5 46 55 64 73 81 69 80 90 101 111 95 107 120 131 143 110

273.0 47 56 66 74 83 71 82 93 103 114 97 110 123 135 147 112

323.9 49 58 68 77 86 73 85 96 107 118 101 114 127 140 152 117

355.6 49 59 69 78 87 74 86 98 109 120 103 116 130 143 156 119

406.4 50 61 70 80 90 76 88 100 112 123 105 120 133 143 156 122

457.0 51 62 72 82 92 78 90 102 114 123 108 120 133 143 156 122

508.0 52 63 73 83 89 79 92 102 114 123 108 120 133 144 157 122

610.0 52 63 73 83 90 79 92 102 114 124 108 121 135 148 161 123

Flat surfaces 56 68 80 93 105 87 103 119 135 151 126 145 1

Documents

BS-ISO 12241