Provisional Report - Eco Open Houses

130212- 1306-1-Exeter Hall carbon report www.greenbuildingpartnership.co.uk

“Working together to reduce energy costs and carbon emissions”

Client:

Exeter Street Hall

Property Ref:

Exeter Hall

Provisional Report

Exeter Street, BN1 5PH

Report Reference:13-06Assessor Name: John Smith

Signature: Date of Survey: 27/11/12

Client:

Exeter Street Hall

Property Ref:

Exeter Street Hall

http://www.cityzendesign.co.uk/

http://www.greenbuildingpartnership.co.uk/


Executive Summary To determine the potential for energy and carbon saving at Exeter Street Hall a brief site survey was

conducted and preliminary report produced with draft recommendations based on the following

sections within the report:

Site Observations Graph of benchmark energy consumption

Site heat loss Site recommendations Carbon emissions from site energy use Vs potential emissions after recommendations

applied Capital expenditure of options

Renewables

This is a draft report with energy consumption based on industry benchmarks for the expected

consumption of a church, village or club hall, i.e. intermittent usage by the public. The industry benchmark is based on gas heating and hot water and electricity for lighting and occupant uses. This type of building is deemed to have a low energy demand both for electricity and gas due to its low

level of use.

In Exeter Hall gas is only being used for water heating so the gas consumption is likely to be lower than expected, and the electricity, being used for heating and lighting is likely to be higher. The

overall consumption for the actual building may in fact be higher or lower than the benchmark if for example, the hall usage is significantly different to that of the “average hall” used to develop the benchmark data. Also if the construction and services within the actual building are more or less

efficient than the those in an “average hall” this will also impact on the actual consumption.

At a previous point the heating was natural gas, but on site it appears that this gas fired system has been condemned and heating is now from point of use electric heating. While electric heating is

efficient, the convection heaters have insufficient output for the large spaces to be heated.

When considering how to address the improvement of a building the fabric must always be considered prior to the services (heating, hot water). The building envelope must be sealed with the

building fabric improved so that the structure is as efficient as possible. Thus the heating demand can be accurately calculated and will be as low as possible.

All cost savings are theoretical and have been calculated based on the benchmark consumption for a

comparable building and electricity unit price of 10p/kWh and gas unit price of 4p/kWh. The calculations have been based upon the assumption that gas will be the heating fuel used.

Way forward: Collate a year's worth of energy bills to feed into this report to create a more accurate view of consumption, it would be interesting to include periods were gas heating was in use. Investigate the potential for obtaining the NCT data file from the assessor that produced the EPC. This represents a valuable and significant data resource that can be used to model options for refurbishment going forward.




Short-term Recommendations

1. Draught proofing is a key requirement of the hall. In terms of airtightness the structure is not sound. There are large gaps around doors, there is cracking in the walls and evidence of water ingress. Window frames are in a poor state of repair. Addressing the fabric of the building to ensure any heat generated is not lost through draughts could save up to 20% of the heating costs.

2. The lighting is inefficient and is the easiest way to reduce electricity consumption. Ensure all lights

are efficient and not in use when not required. As lights require replacing install LED or high frequency fluorescents where equivalent LED fittings are not available. Estimated saving through

replacement of lighting 25% of potential total electricity demand, estimated £88 of theoretical electricity cost.

3. Install energy meters to monitor electricity use of different services, collate information to enable hall management to establish patterns of use and to create user awareness through reporting of usage.

Mid-term (1 year) Recommendations

1. Optimise lighting use with PIR sensors.

2. Evaluate the condition of the windows, if condition is salvageable install secondary glazing saving around 6% of theoretical gas demand, if require refurbishment or replacement ensure the glazing and frame unit specified has a low U value, high energy efficiency rating.

Long term Recommendation

1. Once the building has been draught-proofed and upgraded in terms of insulation the heating

demand should be accurately calculated and a system installed that meets the needs of the occupants. Use weather compensation and optimum start/ stop controls to optimise the use of the heating.

2. Consider installing PV to supplement the electricity used on site, a PV array of 20 m2 on the SW

slope could supply 40% of the annual site electricity requirement saving over £557p.a. in theoretical electricity costs. As the site does have overshadowing, a full solar model should be obtained before proceeding to establish the extent of the shadow. If the building achieved a D rated energy

performance certificate it would be eligible for £349 p.a. of Feed-in-Tariff. (EPC may be negated if applied for as a community scheme, check with the FIT provider)

3. Solid wall insulation could save 16% of the heating demand, equivalent to £146 p.a. of theoretical gas costs. However, this is a very costly measure and would not payback unless the heating use of the hall was considerably more than the benchmark to begin with.

4. Improve the thermal performance of the roof, potentially reducing estimated gas demand by 36%, saving equivalent £ 328 p.a. theoretical costs.

5. Insulating under the floor is an option for saving around 5% of theoretical gas demand, though is not as cost effective as insulating the roof, the roof being the largest area of heat loss.




CO2 emissions from benchmarked energy use

7 tonnes CO2 per year

(N.B. The EPC produced in 2011, is a detailed model of actual construction and services in the building the heating system has changed since this was produced and so the data will need to be updated)

Estimated Energy and Carbon Savings

Underfloor insulation: 5% gas saving: 0.2 tonnes CO2 per year

Secondary glazing: 6% gas saving: 0.3 tonnes CO2 per year

LED lighting: 25% electricity saving: 0.6 tonnes CO2 per year

Solid Wall insulation: 16% gas saving: 0.8 tonnes CO2 per year

Roof insulation: 36% gas saving: 1.7 tonnes CO2 per year

PV installation: 40% electricity generated: 0.9 tonnes CO2 per year

N.B. Without sub-metering data for separate heating, lighting all figures are derived from an estimated proportion of the total energy demand.




Information:

Summary of Observations:

Building Fabric

Estimated date of construction

Building History (i.e. extensions etc)

= Not Applicable/Present

= Non-compliant/Hazard/Urgent Attention Required

= Satisfactory/Requiring Attention

= Good/No Action Needed

General Condition In need of repair and air tightness 3

By Element:

Walls: - Type Solid walls newer extension likely to be cavity 4

Comments Walls need attention.

Cracking can be seen externally and internally, a number of points of water ingress through cracks and saturated brickwork, blistering, blooming and mould can be seen at various places

across the front façade. Air gaps, cracks and missing bricks

throughout the façade.

Windows – Type Mix of single glazed metal and timber frames 4

Comments All windows need frame refurbishment,

Doors – Type Wooden 4

Comments Many draughts and heat loss through ill fitting doors

Roof – Type Slate tiles, Multiple pitches 7

Comments Presumed to have minimal insulation

Floor – Type Solid tiled and suspended wooden 5

Comments No insulation beneath floor

Interior Fit Out:

Date of last fit out

Estimated date of Refurbishment 0

General Condition Poor 5




Summary of Observations:

Building Services

= Not Applicable/Present

= Non-compliant/Hazard/Urgent Attention Required

= Satisfactory/Requiring Attention

= Good/No Action Needed

Lighting ~ Internal – Type High pressure vapour luminaire

Comments Not as efficient as LED or high frequency fluorescent

Heating – Type

Comments

Low Temp Hot Water – Type

Gas heating has been decommissioned and replaced

with point of use electric.

Electricity is higher cost but also higher efficiency, the heating is

inadequate for the areas

Electric point of use water heaters and a gas fired

water heater

Comments Several appeared out of service, poorly maintained

If all services were in use electricity usage would be higher than

expected, but as many are out off use consumption will be

erroneously low, if compared to a benchmark

Ventilation – Type Natural ventilation

Comments High level windows top-lights were open despite poor weather

BMS – Type None

Comments

User Controls – Type All manual

Comments

4

5

5

6

7




Gas 2995

cal Building of same usage

Electricity

0

Annual Consumption (kWh)

25000

Consumption: National Benchmarks

2

Typi

4380

In the absence of fuel data national benchmarks are taken from CIBSE TM46. The graph demonstrates what consumption an average building of the same size and use as Exeter Hall would be likely to consume.

The pie chart below shows the estimated percentage heat loss from the various areas of the building. This is

based upon the estimated construction of the various building elements. By re-running a heat loss calculation with alternative construction an estimation the benefits of addressing

each area can be obtained.

Exeter Hall Heat Loss

floor 11% glazing 11%

walls 32%

roof 46%




Summary of Recommendations:

Building Fabric

By Element

Walls Ensure all cracked walls are filled / re pointed

Rectify areas of damp

Solid wall insulation a possibility but costly

Windows

Doors

Provide secondary glazing throughout, or replace glazing with

thermally broken windows with an improved U-value.

Repair or replace, ensure that doors fit and that there are no

gaps allowing draughts

Roof Investigate feasibility of insulating slope to reduce heat losses

Floor

Other

Insulate to reduce heat losses, typically a rigid board cut tight between joists.

Seal all external brick work with a rain repellent finish to reduce

water ingress.

Where any fabric upgrades take place ensure the quality of workmanship, impart to any tradesmen the importance of sealing the building.

Completely seal the building as much as possible to reduce

infiltration losses (once works are carried out a pressure test may be worth while to find any shortcomings).





Building Services

Lighting ~ Internal Change all lighting to LED or high frequency fluorescent

Heating

LTHW

Metering

Controls

Once building has been sealed and insulated calculate required

heating demand and install central heating system

If the building was to be insulated and sealed to modern

standards alternative methods of low energy heating could be

looked at, i.e. air source heat pumps.

Point of use instantaneous electric water heating is most efficient, size appropriately according to calculated demand. Units that incorporate storage should only be used if storage

well insulated resulting in low heat loss.

Meters should be installed to ensure that the consumption is

monitored, thus enabling management to address any inefficient usage.

PIRs to WC and communal areas should be provided as a

minimum. Optimum start/ stop controls and zonal controls

should be provided as a minimum for any central heating

installed.


Sustainability Measures

Renewables

Photovoltaic Array Yes- if a full solar model indicated overshadowing not significant

Estimated area available for PV 20




Site Carbon Emissions: Existing and Potential based

On Energy Demand

Notes:

Energy demand based on benchmark data, carbon emissions calculated using standard carbon factors

published by Defra applied to the energy demand. The impact of insulation was calculated by producing heat loss calculations based on standard U-value

(thermal performance) data gather for each 'element' of the existing building fabric as observed during the site

inspection. The existing U-value data was then revised to reflect possible upgrades allowing the heat loss and

therefore the energy demand to be calculated.

The LED lighting calculation has been approximated, lighting has been assumed to be 50% of the electrical demand, changing to LED lights has been conservatively estimated to give a 50% reduction in lighting

electrical demand (depending on the application LED can result in savings of over 50%).

Option 4 –Secondary glazing to windows 4.4 2.4

Option 3 – Insulate under floor 4.5 2.4

Option 2 –Solid Wall Insulation 4.0 2.4

Option 1 – Insulate Roof 3.0 2.4 Electricity

PV 4.7 1.4 Gas

LED Lighting 4.7 1.8

Existing Building 4.7 2.4

0 1 2 3 4 5 6 7 8

Tonnes of CO2




Capital Expenditure

Carbon Emission Reduction Options

Photovoltaics

Assumptions

Cap Ex

Payback in

years

Total potential

savings after payback

Project

Lifespan in

years

Total savings over

project lifespan

Tonnes of Carbon

saved p.a.

Net Present Value

Index of Profitability

Internal rate

of return

Annual rise in fuel costs and

FIT not included

£5,344

9

£8,909

25

£13,921

0.92

£2,053

1.38

9.5%

Option 1 – Insulate Roof

Assumptions

Cap Ex

Payback in

years

Total potential


Project

Lifespan in

years

Total savings over

project lifespan

Tonnes of Carbon

saved p.a.

Net Present Value


Internal rate

of return

Estimating 2% fuel cost

increase p.a.

£7,898

19

£5,817

30

£13,311

1.69

-£2,003

0.75

1.6%

Estimating 4%

fuel cost increase p.a.

£7,898

17

£10,627

30

£18,403

1.69

-£362

0.95

5.1%


increase p.a.

£7,898

15

£18,303

30

£25,940

1.69

£1,954

1.25

7.6%

Option 2 –Solid Wall Insulation

Assumptions

Cap Ex

Payback in

years

Total potential


Project

Lifespan in

years

Total savings over

project lifespan

Tonnes of Carbon

saved p.a.

Net Present Value


Internal rate

of return


increase p.a.

£16,478.48

30

£0.00

30

£5,904.62

0.75

-£13,863.68

0.16

-56.37%


increase p.a.

£16,478.48

30

£0.00

30

£8,163.07

0.75

-£13,135.71

0.20

-36.65%

Estimating 6%


£16,478.48

30

£0.00

30

£11,506.79

0.75

-£12,108.24

0.27

-22.02%




Capital Expenditure

Carbon Emission Reduction Options

Option 3 – Insulate under floor

Assumptions

Cap Ex

Payback in years

Total potential


Project

Lifespan in

years

Total savings over

project lifespan

Tonnes of Carbon

saved p.a.

Net Present Value


Internal rate of return

Estimating 2%


£8,165.37

30

£0.00

30

£1,891.98

0.24

-£7,327.53

0.1

-96.62%


increase p.a.

£8,165.37

30

£0.00

30

£2,615.64

0.24

-£7,094.27

0.13

-65.62%


increase p.a.

£8,165.37

30

£0.00

30

£3,687.04

0.24

-£6,765.04

0.17

-42.55%

Option 4 –Secondary glazing to windows

Assumptions

Cap Ex

Payback in

years

Total potential


Project

Lifespan in

years

Total savings over

project lifespan

Tonnes of Carbon

saved p.a.

Net Present Value


Internal rate

of return

Estimating 2%


£1,789.00

23

£696.93

30

£2,411.74

0.3

-£720.99

0.6

-2.29%

Estimating 4%


£1,789.00

19

£1,722.29

30

£3,399.58

0.3

-£396.88

0.78

2.53%


increase p.a.

£1,789.00

17

£3,141.25

30

£4,884.25

0.3

£66.02

1.04

5.95%

Notes:

All costs are estimates based on industry book prices and therefore are dependent on products specified and

installers used. Saving on fuel based on 10p /kWh electricity, 4p/kWh gas and based on benchmark

consumption, savings will be increased if building energy demand is higher than the benchmark.

Photovoltaic installation costs are dependent on the size of the installation, panels specified, DNO

Requirements and site access, and achieving the required EPC rating to be eligible for the Feed-in-Tariff.

The index linked increase to the Feed-in Tariff has not been included in this calculation. The FIT is based on

the reduced tariff from the Government released August 2012.

A Controls and lighting option was not modelled for the capital expenditure calculation as sub-metering is

required beforehand in order that the appropriate plant can be ascertained. As such, capital expenditure

cannot be calculated without further investigation.




Renewables

A solar PV installation that could supply around 40% of the annual electricity demand

could be considered. All solar installations from April1 2012 require the building to

achieve a D rating on an energy performance certificate to qualify for the feed in tariff. However, investing in solar PV will be cost effective without the FIT within a few years

due to the increasing cost of grid electricity and reducing cost of PV. A full solar model should be obtained to take into account to the overshadowing of the chimneys

Individual optimisers or inverters are recommended to reduce the effect of overshadowing

Array 1

Panel Type

Income Savings

Feed In

Tariff (13.99p kWh)

Export Tariff 4.5p/kWh (30% of

generation)

Carbon Emission

Reduction (Tonnes

CO p.a.) 2

Electricity used on

site: 10p/kWh

A £321 £31 0.85 £160.80

B £338 £33 0.89 £168.87

C £349 £34 0.92 £174.48

The difference between income and savings of the panels is down to panel performance. Other differences arise between each panel type as shown below.

Panel Type

Size of installation Panel efficiency

Estimated Cost per kW

Number of panels

kW Peak m2

A 16 2.88 20 0.14 £2,845.00

B 12 3.02 20 0.15 £2,188.00

C 16 3.13 20 0.16 £1,710.00

Panel Type A - Globally renowned brand

Panel Type B - Spanish brand, scored No.1 by independent testing lab

Panel Type C - Chinese brand




Survey Photos & Notes

Significant water ingress, showing

throughout the building.

Significant Maintenance is required

throughout the building to reduce air gaps. Reducing air ingress would significantly

reduce the heat losses of the building and

improve user comfort.

Individual heaters and redundant point of use hot water heaters.

Individual heaters would be ineffectual in

this building due to the heat losses.




Redundant Gas fired heaters, C/W flues

running into chimneys. Significant heat losses will be present through the redundant flues

As above




Black mould present upon external walls

of the toilets, inadequate wall insulation, heating and ventilation combined with high

moisture levels.

Electrical services should be checked, made safe or removed as appropriate.




Purpose of document

This provisional survey and report was undertaken to analyse the

property

Exeter Hall

This report is prepared for the sole use of the client and their agents.

The findings, observations and conclusions contained in this report are

based on the findings of John Smith.

It is noted that the site inspection, and all advice arising from the

inspection, are from a purely visual perspective, without carrying out any opening up works or material testing.

The methodology of any works required should be in line with the

needs of the building, local planning conditions and Building Control. As such we shall leave future professionals to comment on the

methods employed.

About us

Cityzen is a multidisciplinary design practice offering full architectural design and energy consultancy. Our services are tailored to the client’s

requirements whether they are businesses, developers or home

owners.

Our architectural design services cover everything you might need from

the very outset of your project guiding you through the process from

feasibility stage to hand-over of the completed property, and everything

in between.

Common services include: – Feasibility Studies – Measured Surveys – Planning Permission Applications – Building Regulations Submissions – Construction Drawings Packages

In addition to this we offer energy reduction services and are accredited

low carbon consultants.

This covers a broad spectrum of services from energy usage and

carbon footprint calculations through to renewable technology system

design and specification. Although this work is often for corporate

clients, these services are available to all clients

Common services include: – Renewable technology feasibility

– Renewable Technology and sustainability reports for planning

applications and clients – Thermal element analysis, U-value & heat-loss calculations – Building energy and emissions modelling up to EPC Level 4 – Renewable technology expenditure and payback calculations

As part of our professional capability we offer support to architects and

other construction professionals and their clients to provide guidance

on sustainability, renewable technologies and waste management statements.



Documents

Provisional Report - Eco Open Houses