Sustainable Approach

CSH

The Code for Sustainable Homes (CSH) was introduced in 2007 to assess the sustainability and carbon footprint of housing in the UK. The standard set out to produce a set of criteria on which a dwelling will be assessed with the aim of limiting the environmental impact.

The main driver of the initiative has been to reduce the contribution of housing to green house gas emissions. Between 40% and 50% of UK’s CO2 emissions are attributable to buildings; two thirds of this to the domestic sector.

The Code is based on a credit system with credit gained for performance within the 9 categories. The credit score is weighted depending on the category, the overall percentage is then calculated based on the weighted score.  The percentage score is split into 1-6 Code ratings, with a nil rated homes ones that meets current building regulations and Code 6 homes being an exemplar dwelling with a zero carbon status.

PassivHaus

PassivHaus is a German standard for the energy used for space heating only. However space heating occupies between 60-75% of energy usage within the home.

The core focus of Passivhaus design is to dramatically reduce the requirement for space heating and cooling. This can be achieved without compromising the comfort and climate of the living space.

Currently, this standard is gaining support in the UK as a means for meeting higher CSH scores in an extremely cost effective manner. Rather than employing numerous expensive renewable technologies the ‘Passiv’ approach focuses on energy efficiency through super-insulation and heat recovery.

These standards for insulation, u-values, airtightness, and window performance go far beyond any criteria illustrated in the Code for Sustainable Homes. A Passivhaus has such a highly insulated envelope that space heating requirements are reduced to almost zero requiring little or no formal heating system whatsoever.