3) The Green or Passivhouse


When considering what type of new housing in either a urban or rural context consideration should be given by both small and large charities on the impact of their activities upon the environment whilst also seking to save money. One of the great challenges of our time is to create an environment as carbon emmission free as possible in order to reduce the impact upon the environment. The `green-house` gas emission from residential housing/buildings is substantial whilst also absorbing considrable energy/costs.These are already prohibitive for organisations and also individuals experiencing `fuel poverty ` on low incomes.

One major step forward is the `Passive` house which maximises insulation and renewable energy sources whilst also reducing running costs.The principle is simple -prevent expensive heat loss saving 90 % of energy costs with super insulation, air tightness, maximising solar gain and preventing cold bridging. Mechanical ventilation provides heat recovery in winter and cooling in summer alongside fresh filtered air. The challenge is to produce housing which is capital and revenue cost effective and green.


In our northern climite the average heating demand is 150KWh /m2 a whwereas for a Passive house the requirement is a mere tenth of that obtained via renewable sources. Because of very high insulation the winter coldness stays outside the building and conversley in summer the heat stays outside so the internal temperature remains constant and comfortable.


The Passive house has an efficient ventilation system which control the internal environment preventing odours, moist air, mould & dust with resultant allergies. The ventilation unit has a heat exchanger which either heats or cools the air depending on the season and internal temperature.

Windows & noise

On normal days Sunlight (especially in south facing windows) can produce substantial heat gain with U values of 0.58W/m2 K. In winter energy loss is substantially reduced via tripple glazing filled with Kryton or argon gas. Noise transmission can be considerably reduced depending on the the frame materials,insulating glass,window and building sels etc.

Renewable energy

The Passivhause are circa one-tenth of a conventional building with heating requirements of 15Kwh/m2a and hot water of < 120 Kwh/m2 depending on systems used. So using either to Solar Thermal or Solar PV , or thermodynamics any deficit can be met.

Funding & Costs

We are currently looking at the above in order to provide advantageous solutions to new built,refurbishments or retro-fitting including new Passivhouse construction to meet needs within the charitable sector. In an era of change this is one of our most exciting projects.


If you would like some further information on how we can help you with new development in this area please contact john@caracommunity.co.uk or telephone 01803852270. Our conversation is entirely free.