Project title: Westwood Community Primary School, Maple ... › files... · 19.07.2017 · Project title: Westwood Community Primary School, Maple Grove, March, PE15 8JT. Mechanical

Project title: Westwood Community Primary School, Maple Grove, March, PE15 8JT. Mechanical Performance Specification

Date 19-07-17 – Initial design review

Westwood Primary School Expansion –Mechanical Services Specification

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Contents MECHANICAL SERVICES ............................................................................................................ 3

1 INTRODUCTION .......................................................................................................................... 3

1.1 General .................................................................................................................................. 3

2 DESIGN ......................................................................................................................................... 3

2.1 Engineering Philosophy ................................................................................................... 3

2.2 Design Standards ............................................................................................................... 4

2.3 Overview of Services Strategy ....................................................................................... 5

2.4 CDM ....................................................................................................................................... 5

2.5 Asbestos............................................................................................................................... 6

2.6 Plant Access for Test and Commissioning ................................................................. 6

2.7 BREEAM ............................................................................................................................... 6

2.8 Incoming Services ............................................................................................................. 6

2.9 Plant Access and Maintenance ...................................................................................... 7

2.10 Domestic Water Services ................................................................................................. 7

2.11 Natural Gas Services ......................................................................................................... 7

2.12 Heating .................................................................................................................................. 8

2.13 Ventilation ............................................................................................................................ 9

2.14 Controls ................................................................................................................................ 9

2.15 Energy Monitoring ............................................................................................................. 9

3 DRAWINGS SCHEDULE ......................................................................................................... 10


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DOCUMENT CONTROL SHEET

Name Initials Date

Prepared Agnieszka Kaminiarz AK 19 July 2017

Checked Agnieszka Kaminiarz AK 19 July 2017

Approved Ioannis Papanikolaou IP 19 July 2017

Revision -


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MECHANICAL SERVICES

1 INTRODUCTION

This document provides an outline description of the mechanical engineering services for the proposed project to develop The Westwood Community Primary School, located at Maple Grove, March city. The development comprises the refurbishment of existing building and a new building extension to provide a new 4 classrooms block, break out area, office, staff facilities.

1.1 General

The building services shall be designed to:

■ Provide all materials and works in accordance with the current Building regulations, Building Bulletins, British Standards or Code of Practice.

■ Ensure all equipment and systems are designed and installed in accordance with the relevant standards and that operational compatibility exists between the systems and any other system installed at the same location.

■ Supply plant and equipment to achieve the specified design conditions and to provide stable control.

■ Comply with the requirements of the Local Building Control office.

■ Allow easy access for maintenance of the equipment.

■ Minimise health and safety risks to maintenance operatives and others.

2 DESIGN

2.1 Engineering Philosophy

The engineering services design approach shall focus on a number of key design goals. These have

been identified and summarised below (although not limited). These design goals shall be used during

the design development in order to provide a building that can:

■ Meet the current and future functional needs of the building and its occupants

■ Offer a high quality internal environment

■ Considers the schools teaching needs

■ Be safe and secure

■ Be flexible in its usage and operation

■ Respond to future change (e.g. teaching, operational, layout and technological change etc.)

■ Make creative and maximum use of natural light

■ Minimise energy usage

■ Maximise use of passive environmental control (daylight, natural ventilation, good thermal insulation etc.)

■ Minimise maintenance requirements and costs

■ Offer value for money

The design of the engineering services will be in accordance with the client brief and associated

technical design guidance notes (e.g. DFES Building Bulletins).


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2.2 Design Standards

External Design Temperature

Season Dry bulb Wet bulb Relative humidity

Winter -3°C -3.6°C 100%

Summer 33.6°C 22.4°C 50%

Source: CIBSE Guide A

Internal Design Temperature

Room Winter temperature Summer temperature

Naturally Ventilated Classrooms 20°C No more than 120 hours >28°C and internal temperatures shall not exceed 32°C The average internal to external temperature difference should not exceed 5°C

Offices, Group Room, Caretakers office

20°C As Above

Main Hall 20°C As Above

Toilets 18°C N/A

Circulation Space , Cloakrooms 18°C N/A

Access hygiene Shower 21°C N/A

Source: CIBSE Guide A 2015 Table 1.5 and BB101

Fresh Air Ventilation Rates

Space Ventilation Rate Carbon Dioxide Level

Classrooms (Naturally Ventilated)

Min 3l/s/p, Daily Average of 5l/s/p, and system capability of achieving 8l/s/p

5000ppm MOA, 1500ppm average capable of reducing to 1000ppm

Office 12l/s/p No Control

Toilets 8-10ach N/A

Source: Building Bulletin 101 and BREEAM for Offices 2011

Acoustic Criteria

Space NR Level

Classrooms 30 generally/35 (In summer)

Offices 35

Toilets 45

Circulation 35

Source: Building Bulletin 93

Noise levels from all plant and equipment should not raise the existing background noise in excess of

3dB(A) between the hours of 07:00 and 23:00 (over any one hour period), and between the hours of

23:00 and 07:00 the acceptable period is decreased to 5 minutes, at the boundary of the premises.

Regulations and Standards

All mechanical, plumbing and process systems shall be designed and constructed in accordance with

current good practice to comply with the following governing standards:

CIBSE Guides for Installation and Commissioning

BS and EN Standards

The Building Regulations


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BSRIA Guidance

Local Standards and Guidelines having jurisdiction

Water Service – BS EN871 and Water Requirements 2000

Rainfall Intensity – BS EN12056

Gravity Drainage Systems Inside Buildings – BS EN12056

External Building Drainage – BS752

Temperature Maintenance Tape – CIBSE, TM13, BS6700 and BS6351

Other relevant international guidance/standards such as ASHRAE shall be used where

appropriate.

Local Water Supply Company Bylaws.

Recommendations of the Health and Safety at Work Executive.

HSE Legionnaire’s Disease – The Control of Legionella Bacteria in Water Systems – Approved

Code of Practice and Guidance

The governing standards applicable to this project shall be those in effect at the time of contract award

and those versions currently acceptable to the authority having jurisdiction.

2.3 Overview of Services Strategy

The Careful consideration has been given to the building services engineering concepts and integration

with the architectural design concept. The design strategy acknowledges the environmental criteria for

the space and the need to maximise energy efficiency.

New services shall be installed throughout, except where specifically noted otherwise. All areas shall

be naturally ventilated with heating provided via radiator emitters heating system or underfloor heating

system. The existing building is a single storey school building that shall be refurbished and replaced

with a new Low Temperature Hot Water (LTHW) heating system, using cased radiator emitters and a

new underfloor heating system which serves a new 4 classrooms block extension. The heat for the

existing building is provided by main boiler plant serving the whole building, located in the basement

plantroom. The boilers are 2No condensing, floor mounted Ideal Harrier GTE 280 kW boilers. The

boilers and the heating system shall be commissioned at the right temperature 80/60°C heating flow

and return. The existing main boiler room equipment shall be remain. The proposed refurbishment area

shall be heated by the new radiator emitters in casing in the same location as existing or removed to a

new location as stated on the drawing. The proposed new extension and kitchen area shall be heated

via a new condensing Heatmaster 85TC combination boilers. The existing school hot water supply is

provided by the local point of use electric water heaters located into the Sink/WHB’s Cupboards as

indicated on the drawings. The new hot water supply shall be generated via Heatmaster 85TC

combination unit to serve a new classroom extension and kitchen area. The existing drainage system

should be remove and reconnect with a new in proposed location as indicated on the drainage layout.

Mostly all of the space office should be naturally ventilated. If it is not possible then Extract Fans will

extract air from the landlocked MI Room, Repro room or toilet spaces, as indicated on the ventilation

layout. For more details please refer to the specification below and the MS4 drawings.

2.4 CDM

Consideration of safety shall be paramount at all times.


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There are no abnormal, unusual or significant hazards/risks over and above those that would be

anticipated on a project of this nature and that would be expected to be within the normal management

duties of a competent contractor with experience of this type of work.

2.5 Asbestos

Consideration The Contractor shall inspect the premises' Health and Safety File for records of asbestos

or other substances prior to commencing the works.

The appointed Contractor will be required to inspect the Property Asbestos Log Book (for buildings

where they exist) prior to carrying out any works on existing buildings, and must sign in the appropriate

column to confirm he has done this. The Contractor will be required to follow the procedures set out in

the Log Book. If the Log Book indicates that the area of works will disturb asbestos, the Contractor must

inform the engineer and await instructions.

Where during the course of the works, asbestos or other substances are found, which in the opinion of

the Contractor are hazardous to health, any work which involves the disturbance of such a substance

shall be immediately stopped. If working within a ceiling void or duct, close the access covers, or if

working in a boiler or plant room, close the door and put up a notice "NO ENTRY". Inform the engineer

immediately and await further instructions.

If an accident occurs whereby asbestos or other substances are inadvertently disturbed in no

circumstances attempt to sweep up or dispose of it but report to the engineer after complying with the

above requirements.

2.6 Plant Access for Test and Commissioning

Access for Test and Commissioning of plant items and all refurbished and a new mechanical services

installation was allowed in the project. The Contractor should test and re-commission the existing and

new mechanical installation to leave it fully operated in accordance with applicable regulations and

standards.

2.7 BREEAM

The proposed/extension building will achieve a BREEAM ‘Very Good’ rating.

The appointed BREEAM Assessor will indicate in future stages of the project the requirements for the

M&E services to be carried out in order to achieve the required rating within the BREEAM pre-

assessment. We have allowed for the BREEAM Assessor to achieve all BREEAM Credits as required

under the Client’s Requirements.

2.8 Incoming Services

The existing school is provided with gas and water meters located within the site boundary. We have

allowed for the upgrade of the existing water supply as required to serve all new extension areas. A

provisional sum has been allowed for the upgrade of the main water supply.

For water application further details of the quotation, please contact Lisa Stephenson at email address:

[email protected] on the phone number 03456 066 087 option 1.

mailto:[email protected]


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2.9 Plant Access and Maintenance

Access for maintenance and/or replacement of plant items and components was allowed and co-

ordinated with all services during MS4 stage and shall be strictly in accordance with BSRIA Technical

Note TN/92. Plant room layout and development will continue as necessary at MS4 stage and beyond.

2.10 Domestic Water Services

2.10.1 Cold Water Service

A new incoming water mains service to the school extension was allowed to serve the proposed

mechanical services plant room at ground floor level. The new incoming water mains pipe work material

shall be MDPE. Please see MS4 Drawings for further details.

The new incoming water mains service will be metered with a pulsed output (upon entry to the plant

rooms) and connected to the upgraded Building Management System (BMS) to monitor the water usage

and consumption. A separate water sub meter will be provided to the kitchen area, all as indicated at

MS4 stage Drawings.

For further details on the selection/design/specifications, please refer to the MS4 drawing number

Westwood-KWS-03-00-DR-M-001-003 Proposed Domestic Services, Westwood-KWS-XX-XX-DR-M-

001 Plant Room Schematic.

2.10.2 Hot Water Service

New independent domestic water hot water system will be provided to the new extension areas via gas

fired high efficiency Heatmaster 85TC combination boiler. The system shall be mains fed and a fully

pumped system to maintain required minimum system temperatures to prevent any bacterial

(legionella) growth. The hot water storage shall be maintained at 60°C at all times and the system shall

be designed to provide return temperature of minimum 55°C. The pipework shall be fully insulated, in

accordance with BREEAM requirements and all branches shall be provided with isolation valves and

thermostatically controlled temperature balancing valves.

All hot water outlets (with the exception of kitchen equipment) shall have lockable and adjustable

thermostatic mixing valves installed as near to the source of draw off points to prevent scalding and

minimise the risk of Legionella. Selection of TMV valves shall be strictly in accordance with BREEAM

requirements. All TMV valves shall be fully accessible for maintenance purposes.

For further details on the selection/design/specifications, please refer to the MS4 drawing number

Westwood-KWS-03-00-DR-M-001-003 Proposed Domestic Services.

2.11 Natural Gas Services

A gas supply is provided to the school main plant room, all as indicated at MS4 stage Drawings. The

modifications of the gas pipework was allowed in the main plantroom and on the existing school building

as indicated on the Westwood-KWS-XX-XX-DR-M-002 Kitchen Modifications and Westwood-KWS-07-

00-DR-M-001 Plant Room Layout. The gas pipework shall be sub metered to the heating gas fired

condensing boiler /hot water combination unit to comply with BREEAM requirements.


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We have allowed for all sub-meters to be installed in the existing plant room area or otherwise stated

on the Westwood-KWS-XX-XX-DR-M-001 Plant Room Schematic.

Gas solenoid valves and emergency gas safety panels shall be installed in the plant room to provide a

complete installation. The appointed M&E consultant at MS4 stage shall work closely with the Main

Contractor to ensure that all gas solenoid valves, gas knock-off button, gas sensors above boilers are

allowed, design, installed as necessary to provide a complete installation.

We have allowed a provisional sum for the upgrade of the existing gas services

2.12 Heating

2.12.1 Low Temperature Hot Water Heating

Plant

The new extension heating will be served via a plant comprising of a highly efficient internal gas fired

condensing boiler. The arrangement and sizing of the plant shall ensure that the plant provides

optimum efficiency and minimum of 10% of renewables requirement for the total extension energy

usage. The controls of the gas fired condensing boilers shall be designed to ensure the system will run

smoothly and efficiently. A correctly sized buffer vessel, pumps sets shall be provided.

Two gas fired condensing boilers shall be installed in the main plant room, all as indicated on the

Westwood-KWS-XX-XX-DR-M-001 Plant Room Schematic drawing. The boilers shall provide the

necessary heating to the extension areas only.

Pressurisation unit and expansion vessels shall be installed in the boiler plant room area, all as indicated

on the MS4 stage Drawings.

We have allowed for the underfloor heating specialist to provide a complete design and installation of

underfloor heating system to the extension areas, all as indicated on the MS4 Stage Drawings. The

underfloor heating system (allowed HTG F&R 50/40°C) shall come complete with the appropriate zone

control system to allow for locally adaptable thermal comfort operable by the user as necessary.

The underfloor heating specialist will calculate and provide the correct number of UFH manifolds. All

UFH manifolds will be installed in an easily accessible area and fully enclosed to avoid future damage.

The existing heating system will be disturbed/modified as necessary (in particular around the main

kitchen and surrounding existing office/toilet school areas) to allow the refurbishment works of the

existing heating system, all as indicated on MS4 Stage Drawings. We have allowed for all redundant

equipment to be dis-connected and removed from site, as indicated on the MS4 Westwood-KWS-02-

00-DR-M-001-003 Proposed Heating drawings.

Due to recent modifications that were carried out in the Kitchen area, it will be necessary for the existing

radiators to be retained in a new LST covers, as indicated on the MS4 Drawings. We have allowed for

a wall mounted modular electric heaters with thermostatic control to be provided and raise the room

temperature to a minimum of 18°C. All electric heaters to be provided with a LST cover system to avoid

risk of burning as indicated on the Westwood-KWS-02-00-DR-M-003 Proposed Heating 3OF3.

For Heatmaster 85TC Units further details on the selection/design/specifications, please contact Mark

Evans from ACV UK Ltd. at email address: [email protected] and a phone number 07824 360675.

mailto:[email protected]


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2.13 Ventilation

2.13.1 Natural Ventilation

Our ventilation philosophy is to utilise Natural Ventilation in all classrooms and offices areas within the

new extension, by means of openable windows.

Classroom areas will be provided with high level windows operated manually by Teleflex gear. CO2

sensors shall be installed in each classroom completed with wall mounted traffic light display

(Red/Amber/Green) to monitor/control the CO2 Levels.

We have carried out a thermal simulation analysis to validate and confirm that the windows provided

are sufficient and in compliance with BB101 Standards. The thermal simulation analysis have achieved

a PASS result and all relevant reports and documentation are included in a separate report for clarity.

An allowance has been made to further develop and finalise the thermal simulation analysis from MS4

stage and beyond.

2.13.2 Kitchen Ventilation

Upon carried out an inspection to the existing kitchen area, we’ve identified that the existing kitchen

ventilation system is not in compliance with the latest regulations. Therefore, we have allowed for the

existing kitchen supply and extract fans (supply and extract) and associated ductwork to be removed in

its entirety and a new kitchen ventilation system to be installed in compliance with DW172, DW144 and

BS6173-2009.

We have allowed in our cost for the appointment of a kitchen ventilation specialist (to provide a complete

kitchen ventilation system.

2.13.3 Toilet Ventilation

All WC areas with an external wall surface shall have its own dedicated inline mounted extract fan

ducted to atmosphere via wall dedicated wall kit and louvre. A centralized ducted ventilation system will

be installed within all internal WC areas and discharged to atmosphere via roof cowls or weather proof

louvers, all as indicated on MS4 Westwood-KWS-01-00-DR-M-001-003 Proposed Ventilation Drawings.

We have allowed in our design for the selection and design of suitable door transfer grilles to allow

positive pressure of air to enter all WC areas.

2.14 Controls

The existing BMS control panel will be necessary to be upgraded to allow for the control/monitoring of

the extension areas. The BMS Control panel will comprise of time, weather compensation, optimisation

controls suitable for the heating and domestic water plant. The M&E sub-contractor shall allow a control

specialist to provide a new and existing system upgrades of the control panel.

The new kitchen ventilation system will be inter-linked with a dedicated fire alarm control panel, with the

advice and assistance of a Kitchen Ventilation Specialist.

2.15 Energy Monitoring

The In order to comply with BREEAM requirements (ENE credit scoring system), the new gas and water

installation will be provided with the necessary sub-metering to provide a complete installation. We have


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allowed in our budget for the close co-ordination with the BREEAM assessor at MS4 stage and beyond

as necessary to provide all BREEAM credits.

3 DRAWINGS SCHEDULE

REF. DESCRIPTION

KWS-01-00-DR-M-001 Ventilation Services 1Of3



KWS-02-00-DR-M-001 Heating Services 1Of3



KWS-03-00-DR-M-001 Domestic Services 1Of3



KWS-05-00-DR-M-001 Drainage Services 1Of3



KWS-07-00-DR-M-001 Plant Room Layout

KWS-08-00-DR-M-001 Existing Site Services


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KWS-08-00-DR-M-002 Proposed Site Services

KWS-XX-XX-DR-M-001 Plant Room Schematic

KWS-XX-XX-DR-M-002 Kitchen Modifications

Documents

Project title: Westwood Community Primary School, Maple ... › files... · 19.07.2017 · Project title: Westwood Community Primary School, Maple Grove, March, PE15 8JT. Mechanical