Improvement to a 1930s Semi-Detached Property in Whitehaven
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as PDF Low energy and low carbon retrofitting of a three- bed semi-detached house in Whitehaven, Cumbria originally built in 1930's to achieve carbon emission reductions above 80%. This reduction is achieved by following a whole house approach, and prioritising low energy demand through fabric improvements first, followed by tried and tested low/zero carbon systems, to achieve an estimated 85% reduction in carbon emissions as compared to the existing house
Retrofit for the future ZA241K
Improvement to a 1930s Semi-Detached Property in Whitehaven : Project images
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Energy and fuel use
Measured data from renewable generation is not yet available.
Fuel use
| Pre-development | Forecast | Measured | |
| Electricity use | 752.48 kWh/yr | 874.14 kWh/yr | - |
|---|---|---|---|
| Natural gas use | 26803.87 kWh/yr | 3869.72 kWh/yr | - |
| Oil use | - | - | - |
| LPG use | - | - | - |
| Wood use | - | - | - |
| Other Fuel | - | - | - |
| Pre-development | Forecast | Measured | |
| Primary energy requirement | 428 kWh/m².yr | 87 kWh/m².yr | - |
|---|---|---|---|
| Annual CO₂ emissions | 78 kg CO₂/m².yr | 17 kg CO₂/m².yr | - |
| Annual space heat demand | - | 25.93 kWh/m².yr | - |
Renewable energy
| Electricity generation | Forecast | Measured |
|---|---|---|
| 1 kWp photovoltaic panel array | 818.4000244 kWh/yr | - |
| Other Renewables Tech | - | - |
| Electricity consumed by generation | - | - |
| Primary energy requirement offset by renewable generation | 60 kWh/m².yr | - |
| Annual CO₂ emissions offset by renewable generation | 11 kg CO₂/m².yr | - |
Calculation and targets
| Whole house energy calculation method | SAP |
|---|---|
| Other whole house calculation method | - |
| Energy target | Retrofit for the Future |
| Other energy targets | - |
| Forecast heating load | - |
Airtightness
| Date | Result | |
| Pre-development air permeability test | - | - |
|---|---|---|
| Final air permeability test | - | - |
Project description
| Stage | Under construction |
|---|---|
| Start date | 05 July 2010 |
| Occupation date | 20 October 2010 |
| Location | Whitehaven Cumbria England |
| Build type | Refurbishment |
| Building sector | Public Residential |
| Property type | Semi-Detached |
| Construction type | Masonry Cavity |
| Other construction type | 285mm Wall thickness (110mm brick, 65mm clear cavity, 110mm bric |
| Party wall construction | 110 mm Single brick / 285mm unfilled cavity |
| Floor area | 76.4 m² |
| Floor area calculation method | Treated Floor Area (PHPP) |
| Building certification |
Project Team
| Organisation | Roland Hill Ltd |
|---|---|
| Project lead person | Roland Hill Ltd |
| Landlord or Client | Home Group (North West) |
| Architect | Architects Plus |
| Mechanical & electrical consultant | Roland Hill Ltd |
| Energy consultant | Oxford Brookes University |
| Structural engineer | |
| Quantity surveyor | |
| Consultant | |
| Contractor | Roland Hill Ltd |
Design strategies
| Planned occupancy | Default as per SAP as the property is currently unoccupied. |
|---|---|
| Space heating strategy | Heating from mains gas. High efficiency condensing boiler feeding radiators. |
| Water heating strategy | Solar hot water, with high efficiency gas condensing boiler back up. |
| Fuel strategy | Mains gas and mains electricity. |
| Renewable energy strategy | South-oriented 1 kWp photovoltaic panel array to be installed. |
| Passive Solar strategy | Solar gains from south west facing windows. Efficient building fabric to minimise heat loss. |
| Space cooling strategy | Naturally ventilated house, SAP assessment shows overheating risk 'not significant'. |
| Daylighting strategy | Window sizes and positioning provide good levels of daylighting throughout the house. |
| Ventilation strategy | Natural ventilation through manually openable windows , passive stack ventilation for wet areas. |
| Airtightness strategy | Air - permeability of 3m3/hm2 @ 50 Pa is targeted, highest recommended level for naturally ventilated buildings. Upgrading of windows and doors, minimising thermal bridges and insulating and sealing all air leakage pathways will ensure an airtight fabric is achieved. |
| Strategy for minimising thermal bridges | Using accredited construction details, by detailing for continuous insulation and air barrier on external walls to prevent condensation. Party wall insulation to minimise the thermal bridge between the party wall (back and front) and external wall, and to reduce heat losses to the neighbouring property. Where the first floor rooms extend into the roof line, the underside of the ceiling will be lined with a thermal laminate to reduce thermal bridging. |
| Modelling strategy | SAP 2005 was used as the primary modelling tool. All SAP calculations were carried out in the approved SAP 2005 software SAPCalc. A PHPP analysis was also carried out for the final package of measures. |
| Insulation strategy | Insulating the cavity wall to achieve a U-value of 0.15 W/m2K. This will include filling the 65mm cavity with extruded polystyrene and additionally using 25mm of vacuum insulated panels (VIP) as external Insulation; Insulation of the party wall to avoid heat loss from the neighbouring property; Hipped roof will be insulated with 300mm of mineral wool quilt to achieve a U-value of 0.1 W/m2K; Concrete ground floor slab will be insulated with VIP to minimise the increase in the overall thickness of the floor while achieving a U-Value of 0.2W/m2K. |
| Other relevant retrofit strategies | |
| Contextual information |
Building services
| Occupancy | NULL |
|---|---|
| Space heating | NULL |
| Hot water | NULL |
| Ventilation | NULL |
| Controls | NULL |
| Cooking | NULL |
| Lighting | NULL |
| Appliances | NULL |
| Renewable energy generation system | NULL |
| Strategy for minimising thermal bridges | NULL |
Building construction
| Storeys | 0 |
|---|---|
| Volume | - |
| Thermal fabric area | - |
| Roof description | NULL |
| Roof U-value | 0.00 W/m² K |
| Walls description | NULL |
| Walls U-value | 0.00 W/m² K |
| Party walls description | NULL |
| Party walls U-value | 0.00 W/m² K |
| Floor description | NULL |
| Floor U-value | 0.00 W/m² K |
| Glazed doors description | NULL |
| Glazed doors U-value | 0.00 W/m² K - |
| Opaque doors description | NULL |
| Opaque doors U-value | 0.00 W/m² K - |
| Windows description | NULL |
| Windows U-value | 0.00 W/m² K - |
| Windows energy transmittance (G-value) | - |
| Windows light transmittance | - |
| Rooflights description | NULL |
| Rooflights light transmittance | - |
| Rooflights U-value | 0.00 W/m² K |