| Planned occupancy | All residents are expected to remain in occupation throughout. Respite provision will be made during noisy works, or instances where for health and safety reasons the homes should not be occupied. |
|---|
| Space heating strategy | The homes will be heated using a hot water radiator system with TRV's. The existing radiators will be reused but the hot water will be supplied by the shared boiler fed from the roof mounted solar thermal system supplemented by an Andrew's water heater. |
|---|
| Water heating strategy | The water heating will be provided by a shared thermal store heated by solar thermal panels mounted on the roof of the properties. A single system will span all four properties and feed into a single thermal store located at the end of the short terrace. A gas boiler will be used to bring the hot water up to the required temperature. |
|---|
| Fuel strategy | A communal system has been developed to replace the high gas usage of all four properties. The proposed combined gas demand for space heating is 60% lower than the combined predicted current gas demand. Electricity demand is substantially reduced by using efficient appliances and by generating an equivalent amount from Photovoltaics to power the home lighting and items with small power requirements. |
|---|
| Renewable energy strategy | There is a small amount of electrical generation to power CFL or LED lighting and to replace the demand for power from small appliances. |
|---|
| Passive Solar strategy | The proposed terrace faces south so that the solar thermal system will be optimised from the solar orientation and availability. The homes have large windows facing their gardens on the southern side and we will consult with residents on how to gain the benefit of solar gain in the spring and autumn months of the year. |
|---|
| Space cooling strategy | The homes have openable windows and we will consult with residents about how to use these in summer months to ensure that the homes are cooled overnight. The MVHR system will have a summer boost function to allow warm air to be vented and to bypass the heat recovery function. This will allow the home to be kept cool overnight or while residents are away. |
|---|
| Daylighting strategy | The homes enjoy good daylight levels. We will discuss the need for privacy screens that allow in maximum daylight and reduce the need for electric lighting during daylit periods. |
|---|
| Ventilation strategy | The ventilation will be provided with ducted Mechanical Ventilation with Heat Recovery. This will extract stale, and humid air from the 'wet' rooms and provide preheated air to the living room and bedrooms. Training will be given to the residents on how to use the MVHR and how to set the system correctly. |
|---|
| Airtightness strategy | We intend to achieve an airtightness of approximately 1m3/m2@50Pa which is demanding for new construction. We anticipate that these homes are already reasonalby airtight and we expect that we will be able to find and seal cracks and penetrations after the first airtightness test. The external wall insulation will help to provide an air tight skin, and we are bringing this down below the DPC level to ensure that service penetrations are insulated and air tight. |
|---|
| Strategy for minimising thermal bridges | The application of external wall insulation will solve many thermal bridging issues inherent in 1970's cavity wall construction. We will install new windows forward of the original location in the wall and make good the internal finishes. This will help to ensure there is a continuous line of insulation with few, if any, thermal bridges. We will be applying the insulation to all four properties in the terrace, and insulating at ceiling level. The only remaining thermal bridge will be the ground floor, which we will partially deal with by insulating externally below the DPC. The party wall will be dealt with by carrying the ceiling level insulation 500mm up the party wall. |
|---|
| Modelling strategy | We modelled the project in SAP and PHPP. We used SAP to produce the final figures, and took the results from the SAP worksheets into the SAP whole-house extension tool provided to develop the final figures for the existing situation, the full proposal and the individual measures. |
|---|
| Insulation strategy | We plan to achieve a U-value of 0.11 by insulating the external envelope with phenolic board with a polymeric render system finish. We will replace the windows with high performance windows designed to achieve a low U-value of around 0.8. This will depend on the number of tansoms and opening lights and will be determined at Phase 2. The ceiling level will be insulated with 350mm of blown recycled newspaper as the space available is too shallow to easily work in. The eaves will be extended to allow a covering to the external wall insulation and the roof ventilation will be installed at that point. |
|---|
| Other relevant retrofit strategies | We are planning to carry out our package of retrofit measures with residents remaining in the dwelling during the proposed works. We intend to demonstrate our approach can be undertaken with minimal disruption to the tenants and with no associated temporary decanting costs. |
|---|
| Contextual information | We selected a short terrace from the properties available which is south facing to gain the maximum benefit from the solar thermal system. Although all terraces on this estates could house an end of terrace 'energy centre', we chose a terrace with a large unused space on the end to minimise potential problems with the installation. |
|---|
