What do we mean by ‘Eco’?
Lots of developments now use the term ‘eco’ in their marketing. But Forge Bank actually delivers on the promise through PassivHaus design and green energy generation.
Forge Bank homes are built to the PassivHaus standard which dramatically reduces the need for space heating and can reduce heating bills by 90% compared with conventional homes. PassivHaus design achieves this through:
- south facing aspect and very high levels of insulation
- mechanical ventilation and heat recovery (MVHR).
South facing aspect and insulation
The design uses large south facing windows and doors to capture heat from the sun. Windows and external doors are all triple glazed. The external walls, roof and under floor are all designed with very high levels of insulation. Thermal bridging between inner and outer walls is eliminated. The result is negligible heat loss during winter and the temperature of internal surfaces is almost the same as the internal air temperature, providing a very comfortable living environment.
The homes are built to a very high level of airtightness, tested against a leakage level specified in the standard. This is achieved through specialised plastering and the use of tapes and membranes. The result is no discomfort from draughts and no entry of moisture.
The MVHR unit continuously replaces the air in the building with fresh air from outside and, in winter, transfers the heat energy from the outgoing to the incoming air. The result is that PassivHaus homes have excellent air quality and need very little additional heating. Much of the background heating is provided by appliances such as the fridge, oven and hobs. Even the heat given out by the occupants is significant. For times when the outside temperature is low, there is a single radiator and heated towel rail fed from the district heating system.
District heating system
Heating to Forge Bank homes is provided by the district heating system. Hot water from a highly efficient wood chip boiler in the mill building supplemented by over 50m2 of solar thermal collectors is delivered through insulated pipes to each property. Hot water is piped to the kitchen and bathroom via the same system.
Forge Bank will be connected to the community microgrid and each home will have a meter. Power from a 160kW hydro-electric scheme (developed in conjunction with Halton community), along with power from photovoltaic solar panels mounted on the most appropriate roofs, will be used in preference to National Grid electricity which will only be imported when demand exceeds supply.
We will think beyond the buildings in terms of environmental impacts. We will have a car share scheme and organic vegetable deliveries for example. Shared facilities will mean that some things, from washing machines to lawnmowers do not need to be owned by every household. In all, we want to design a neighbourhood where it is very easy to live a sustainable lifestyle.