Nearer to Zero Refurbishment - Pellings: Home › pdf › Nearer to Zero...EST CWI Report 2008 - The...
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Nearer to Zero Refurbishment Alan Davison and Pete Thompson
Nearer to Zero Refurbishment - Pellings: Home › pdf › Nearer to Zero...EST CWI Report 2008 - The thermographic imaging indicated that surface temperatures at lintels remain high
• Introduction• Government Policy - The importance of green refurbishment.• Paying for it – funding and approach to refurbishment.• Importance of setting targets.• Importance of testing and monitoring.• What standards exist?• Examples of exemplar projects involving Pellings LLP.• Questions?• General discussion – sharing our knowledge.
Overview
Pellings Sustainability ConsultantGood Homes Alliance Associate -GHA monitoring programme
Previously:Assisted development of DEFRA NEAT ToolEast Thames Group, Sustainability Advisor, Code assessorHead of Energy Saving Trust UK Best Practice ProgrammeHousing Corporation advisor Decent Homes Standard and Sustainability
Who am I
Presenter
Presentation Notes
Helping Pellings – mention that we have our own ISO14001 in place; it is not just about helping our clients to reduce their emissions but also focussing on our own operations. GHA project demonstrates we have knowledge of issues around pre and post construction testing, monitoring and POE in homes. NEAT tool demonstrates we have knowledge, experience around climate change adaptation. - Assess how well prepared you and your homes are for the current and future weather
– Housing energy use responsible for 27% of UK CO2 emissions
– Within a UK housing stock of 25m dwellings only <1% are new build
– We have a high % of older homes - 36% built before 1939
– In 2050, 85% of buildings will be today’s stock
Green refurbs are government policy
– Target to retrofit 7 million homes by 2020 to include energy efficiency and micro generation.
– A set of measures which goes significantly beyond basic insulation…
Why ‘Green’ Refurbishment?
Presenter
Presentation Notes
Part L1 B – minimum levels of thermal performance; once refurbished a dwelling unlikely to be latered in near future. A legally binding target of at least an 80 percent cut in greenhouse gas emissions by 2050, on 1990 levels) to be achieved through action in the UK and abroad. Also a reduction in emissions of at least 34 percent by 2020. Both these targets are against a 1990 baseline. This Strategy will deliver our commitment to cut carbon emissions from homes by 29% by 2020. By 2015, we want to help every household install loft and cavity wall insulation where it is practical. By 2020, up to 7 million homes will have more substantial improvements such as solid wall insulation or renewable energy generating technologies, while millions more will benefit from access to advice, information and finance
Lets talk Retrofit - The scale of the challenge
Presenter
Presentation Notes
7 million homes by 2020 – Thats 700,000 homes refurbished per year! By 2030 wants all homes refurbished – thats over 1 million homes per year. Properties with solid walls – thats 660K per year!
Its good but its not right
And that’s assuming we get it right!
Paying for it
Presenter
Presentation Notes
Our results for an 80% improvement seem to correlate well with the BRE’s figures – i.e. around £25-£30K plus to get an 80% improvement in carbon
Present funding available CERT Renewable Heat Incentive, (RHi) Green Deal CESP Feed in Tariffs, (FiT) TSB Building Performance
Evaluation Enhanced Capital allowances Intelligent Energy Europe Green Investment Bank NHBC Foundation
Yes the capital and monitoring costs can be expensive
Presenter
Presentation Notes
FiT - Will be reviewed by HMG in 2012 (to ID potential 10% cost savings by 2014/15)
Not just about upfront costs but long term approach
Take a ‘whole house’ approach Assess ‘real’ current performance• Does the current SAP rating tell
you enough?• What about current - CO2 emissions - EPC band- Fuel bills (£ pa)- Water consumption- Testing
Have a range of carbon targets in mind
- ‘Value carbon methodology’- Analyse CO2 savings from each
specific area- Appraise installation costs- Rank measures – i.e. Low £/Kg at
the top- Pick from the top until desired CO2
saving reached
Reducing the costs of paying for it?
Presenter
Presentation Notes
EE opportunities e.g. When installing a new kitchen you could also choose to upgrade the internal wall insulation, low flow taps ..... Wholes house approach – consider the type of house, look at at appropriate EE and also consider RE technologies and include water and waste reduction measures – e.g. The United House example considered value carbon £/kg Co2; £/kWh saved (energy saved) and £/£fuel bill saved.
How can you reduce the costs of paying for it?
• Trial innovative materials• Take a ‘whole life costing approach’• Quality - ensure correct installation and
commissioning• Choose the right technologies• Availability of materials – cost effective and
timeliness• Ensure tenants know how to use systems• Climate change adaption measures vs ‘mal-
adaptation’• Specify evidence base requirements in
refurbishment contracts and ER’s
Not just talking about upfront capital costs
Presenter
Presentation Notes
Trial innovative materials – e.g. Aerogel insulation, pilkington E vacuum glass into existing window frames if house is in a conservation area and you can’t replace glass with double glazing.
• How do you know your worst performers?
• What resources do you have available and what carbon target do you want to achieve?
• Do you also want to achieve wider sustainability targets?
Tools e.g. Ecohomes XB- Allows RSL’s to assess and monitor
environmental performance of stock.
Setting Targets
Presenter
Presentation Notes
How do you know your worst performing homes – via limited RdSAP calcs, limited stock condition database, via tenant complaints around cold homes.... Ecohomes XB - EcoHomesXB is an easy to use desk based self assessment tool which has been designed to: Assess and monitor the environmental performance of housing stock Track improvements made during routine maintenance and minor improvements Provide a constant monitor of performance against a benchmark figure Highlight areas that require attention and help prioritise maintenance and refurbishment works Assist and guide the overall performance whilst recognising the restraints and practicalities facing existing housing.
• Rd SAP v real condition.
• Does property really have full CWI?
• Where are the existing air leakage pathways?
• Thermal imaging helps identify areas of poor detailing.
The need for testing – pre-refurbishment
Presenter
Presentation Notes
EST CWI Report 2008 - The thermographic imaging indicated that surface temperatures at lintels remain high after application of insulation, suggesting strong thermal bridging at lintels. In many cases there could be thermal bridging at junctions between walls and floors. There were were also, in some cases, areas in the cavities where insulation was either of low compactness1 or had voids which were large enough to be detectable by a thermal imaging camera. For each dwelling, heat flow datasets were collected over two-
• Fabric performance, occupant behaviour and services efficiency have effects on energy consumption
• Segregate these to identify where problems lie
• Without base line of fabric performance few conclusions can be drawn from in-use performance monitoring
• Work by LMU and others show that there can be a difference of up to 120% between whole house heat loss as a % of predicted
The need for testing & monitoring – post refurbishment
Presenter
Presentation Notes
Performance measurements revealed dwelling heat loss 54% higher than designed. Performance of heat pump less than designed; operational problems with solar hot ware system. Ok so you have paid for it – how do you know you have done it right? JRHT Elmtree Mews - The Government has set an ambitious target for all new housing to be zero carbon by 2016. With the application of good insulation, improved efficiencies and renewable energy, this is theoretically possible. However, there is growing concern that, in practice, even existing carbon standards are not being achieved and that this performance gap has the potential to undermine zero carbon housing policy. The report seeks to address these concerns through the detailed evaluation of a low carbon development at Elm Tree Mews. The report: evaluates the energy/carbon performance of the dwellings prior to occupation and in use; analyses the procurement, design and construction processes that give rise to the performance achieved; explores the resident experience; draws out lessons for the development of zero carbon housing and the implications for government policy; and proposes a programme for change, designed to close the performance gap
• Inadequate ventilation – review of Part F 2006.
• Installation• Inspection• Testing• Commissioning• Provision of information
Poor installation and commissioning
Presenter
Presentation Notes
Follow new guidance for existing dwellings
• Funders and stakeholders increasingly demanding evidence based approach to carbon reductions
• Thin on standards e.g. BREEAM Domestic Refurbishment
• And what about proposed ‘Local Standards Framework’?
Standards and the evidence base
Presenter
Presentation Notes
Hold up copy of BREEAM Domestic Refurbishment paper. Local standards framework announced by Grant Shapp, Minister on 25/11/10 at NHBC event. Benchmark where you are e.g. Ecohomes XB and know performance – use of BREEAM
Pellings has significant experience of ‘Green refurbishment’ schemes.
‘Greener Homes’
Inside Housing Sustainable Housing Awards 2010 ‘highly commended’Low energy social housing project of the Year.
Winner of the AJ Retrofit Awards 2010Domestic building – large scale (multiple dwellings)
The Aim: To refurbish 20 vacant dwellings of various ages to higher sustainability levels than current Decent Homes Standard
Why? • Help establish a systematic approach
to reducing carbon emissions
• To support other sustainability objectives such as water efficiency, waste minimisation and materials
• To assist the development of standards to measure the sustainability of housing refurbishment
• To test ‘modelled’ vs ‘actual’ performance
‘Greener Homes for Redbridge’
Pellings role – Employer’s Agent and CSH assessors
Partnership working
Presenter
Presentation Notes
Mention East Thames – as I was advising them on the project.
Grant:£2,790,000 grant from the Homes and Communities Agency£800,000 from the London Borough of Redbridge£50,000 from the NHBC Foundation
Works:Total works costs = £700,000 = £35K per property
So no ordinary refurbishment!
Total Scheme Cost = £5million
The Project - Funding
Presenter
Presentation Notes
Note remove all logs except for funded by. State the funding provided by the HCA, the overall project costs etc. Vacant not occupied. Some were Victorian terraces pre 1900, some 1030’s some 1950’s and a few 2002? + 2 and 3 bed properties pepperpotted around the borough – refer them to a map if we have one.
Important to know where you are starting from!
A Pre refurbishment testing
B Desktop modelling including application of New Build Code for Sustainable Homes
C Post refurbishment testing
D Monitoring and POE - How the homes really perform measure up
The Project – Key elements
Presenter
Presentation Notes
EPC – Info on the homes energy use and carbon dioxide emissions. Only when you buy and sell a property Not when you refurbish. SAP – Standard Assessment Procedure; define the energy efficiency – an estimate of the annual heating, lighting and hot water costs per m2. The national average is 43. It goes from 1- 100 Air tightness test – Calculated by creating a pressure difference between the inside and outside of the house when all intentional openings and ventilation systems are sealed. Measures the amount of air that leaks from the external structure. Thermal imaging – Shows temperature difference & heat loss. External shows heat loss from poorly fitted insulation. Internal shows damp area that are cold and moisture conducts heat so you get condensation, damp, mould etc. The darker the area the colder the surface
What do we test and what do we use:• Airtightness (with smoke pencil tests)• Infra red camera• Spot measurements of T, RH and ventilation• IAQ (Formaldehyde, Total VOCs and CO)• Water audit (tap and shower flows, WC types etc)
Individual reports prepared for each property to assist desktop modelling.
Pre and post refurbishment testing
Funded by NHBC Foundation, BRE Trust and Water companies
The ‘real condition of our stock’
1950s SemiAfter shots
Improvements:• Loft insulation (0.16)• 100% CFLs
Still air leakage:• Gaps around boards• Gaps around service
pipes
Still heat loss:• Walls not improved• Cold air ingress
-5.1°C
7.4°C
-4
-2
0
2
4
6
SP01
Example A – Decent Homes Plus - After
1950s SemiAfter shots
Refurbishments costs
Decent Homes Environmental Costs
Total Cost
£14,985 £353 £15,338
Example A – Decent Homes Plus - After
Significant air leakage:
• Crack in bay window
• Window casements
• Ceiling and floor
Uniform heat loss:• Cold air leaking up from
floor void• Loss at eaves• Loss in front bay
8.3°C
18.5°C
10
12
14
16
18
SP01
1930s End terrace118 Brian Road
Example B – Highly sustainable refurbishment – Before
Presenter
Presentation Notes
This example is 116 Brian Rd Costs for 118 Brian Road (Code 1)DHS costs £14,634env costs £591CSH costs £26,129 total costs £41,354
Significant air leakage:
• Crack in bay window
• Window casements
• Ceiling and floor
Uniform heat loss:• Cold air leaking up from
floor void• Loss at eaves• Loss in front bay
8.3°C
18.5°C
10
12
14
16
18
SP01
1930s End terrace118 Brian Road
Example B – Highly sustainable refurbishment – Before
Presenter
Presentation Notes
This example is 116 Brian Rd Costs for 118 Brian Road (Code 1)DHS costs £14,634env costs £591CSH costs £26,129 total costs £41,354
1930s End terracePhoto After shot
Improvements:• Loft + int. wall insulation• Improved heating• 100% CFL• Solar thermal and PV• Low-flow taps
Reduced air leakage:• Most floor gaps filled• Still gaps around window
casements
Reduced heat loss:• Still some wall heat loss• Some cold air ingress at
windows• Cold floor
1.9°C
13.9°C
2
4
6
8
10
12
SP01
Example B: Code refurbishment - After
1930s End terracePhoto After shot
Refurbishments costs
Decent Homes CSH Costs Total Cost
£14,634 £26,720 £41,354
Example B: Code refurbishment - After
Sustainable Refurbs• 10 properties achieved reductions in carbon ranging from 62% to 82%.• CSH level 3 for water.
Decent homes plus measures• Reductions in carbon ranging from 7% to 44%.
Improvements in carbon emissions
Pellings involvement - Building Surveyors, Cost Consultants and CDM Co-ordinators.
• First PassivHaus retrofit in England.
• Requires minimal energy demand for space heating and cooling.
• The aim is to reduce CO2
emissions by 83%, energy use by 94% and save the tenant in excess of £900 a year on fuel bills.
• How much more will this cost than a typical Decent Homes refurbishment – is it replicable?
• What is a low energy home like to live in?
Why is the project unique?• Funded by the TSB ‘Retrofit for
the Future’ fund.• Pre refurbishment testing.• Post refurbishment testing.• Monitoring – ‘modelled’ vs ‘actual’.• Post Occupancy Evaluation,
(POE).
Green Octavia
Presenter
Presentation Notes
An energy efficient building that has Year round comfort and good indoor Climate without the use of active space heating or cooling systems. The space heating requirement is reduced by means of passive measures to the point that there is no longer any need for a conventional heating system. UK Passiv Haus Standard for both new & existing homes. The average UK home uses 130kWh of energy per m2 per year for heating & cooling. Maximum space heating & cooling demand of less than 15 kWh/m2/yr. Specific heating demand of 25 kWh/m2/yr for existing homes. http://www.greenoctavia.org.uk/how/ Pellings have been appointed by Octavia Housing & Care as the building and quantity surveyors, and CDM Co-ordinators, to assist OH&C and its partners to carry out the low carbon retrofit of a terraced Victorian property, in poor condition situated within a conservation area in Notting Hill, London. Only around 8 in the UK refurbished to this standard! Reduce heat demand via means of insulation, heat recovery, superwindows, passive solar gains and other measures, the heating system can be simplified step-by-step. But the most significant threshold appears when the peak heating load reaches 10 W/m². When the peak heating load is less than 10 W/m², independent of climate, the ventilation system can easily be used for space heating, and a separate heating system is no longer required. The primary function of the ventilation system is to maintain excellent indoor air quality. If the maximum load is lower than 10 W/m², the ventilation system can distribute all heat needed throughout the building as well http://www.sphc.co.uk/passivhaus-retrofit. Occupant body heat and background heat from appliances and lights provides most of the heating http://www.sphc.co.uk/passivhaus-comparison. For those that do want additional heating, the low heating demand of less than 15kWh per square metre per year means that annual fuel costs are reduced by a factor of 5-10. For example a household living in a 70 m2 Passive Energy House with gas heating could spend as little as £25 on space heating each year. BREEAM excellent houses don’t guarantee low fuel costs and whilst Passivhaus space heating is limited to 15kWh/m2/year, a worst-case Code Level 4 house could have a space heating demand of up to 130kWh/m2/yr Primary energy demand is the total sum of the heating, hot water, cooling, auxillary and household electricity. Passivhaus is a German low energy building standard. A Passivhaus has very low energy and heating requirements gained through being very airtight, using natural energy and reusing wasted energy. The average UK home uses 130kWh of energy per m2 per year – to qualify as a Passivhaus our home will need to use less than 15kWh. A pressure test is also required
Green Octavia – reducing the heating demand
Average UK home uses 130kWh ofenergy per m2 per year for heating &cooling.
For existing homes specific heatingdemand of 25 kWh/m2/yr.
Reduce the heating demand byimproving the thermal envelope
• Insulation - to 0.1 U value applied to the front, rear and party walls.
Current building regulationsrequires only 0.25.
• Air tightness of 0.6 Current regs 10
• Thermal bridging – Joists contained within warm envelope
• Windows and doors – Triple glazed (0.6) with insulated frames (1.2)
Green Octavia – Heating & cooling
• Ventilation & heating provided by MVHR unit.
- Stale air constantly replaced withfresh air- Noisy extractor fans are not needed in the kitchen or bathrooms.
• Heat pump in MVHR tops up heating
• Labyrinth heat exchanger –warms outside cold air by the heat of the ground
- Pre heat in winter, cooling in summer
Green Octavia – Hot water
• Solar Thermal- Provides 70-75%, (higher than most
systems due to drain back technology
• Waste Water Heat Recovery
• Air Source Heat Pump within MVHR unit
• One of Lambeth Council’s largest housing refurbishment projects transforming almost 300 flats in three 40 year old dilapidated tower blocks in Kennington, South London
• Renewable energy will be generated on site via one of the largest Photo Voltaic panel arrays in the country, extending to over 900sqm
• CHP plant• Buffer vessels store excess heat
from CHP
Ethelred Estate – shortlisted for Building Magazine ‘Sustainable Refurbishment project of the year’
Presenter
Presentation Notes
A scheme in Kennington. Picture shows PV array. In addition, a gas fired CHP unit providing district heating and hot water will provide further electrical generation for the council which hopes to use it either as an energy services company or to sell electricity to the national grid, so profits can be reinvested into local services.
• Very low levels of air tightness• Average 80% reduction in Carbon• Green roof• Site Waste Management 92-97%• Water efficient products• POE• EU funding was secured.
Ethelred Estate – shortlisted for Building Magazine ‘Sustainable Refurbishment project of the year’
Presenter
Presentation Notes
A scheme in Kennington. Picture shows PV array. In addition, a gas fired CHP unit providing district heating and hot water will provide further electrical generation for the council which hopes to use it either as an energy services company or to sell electricity to the national grid, so profits can be reinvested into local services.
