Responding to the draft TGD L(2010)
A draft version of the new TGD L(2010) is currently on Public Consultation, which is aimed to achieve 60% reduction on energy consumption from 2005 standards. It has good points but many weak areas:
Internal insulation, U-value and condensation risk
The inter-relationship of U-values & inter-stitial condensation The location of insulation within a wall has a large bearing on how moisture and vapour move through it, and to what level it can be safely insulated. This is not evident in TGD L. From the perspective of inter-stitial condensation we find …
Thermal bridging in the new TGD L(2010)
Introduction The Ψ or Psi-value (W/mK) of a thermal bridge describes its extra over heat loss not accounted by the U-values of the adjoining walls, roofs or floors. It depends on several variables such as the U-value of the flanking elements, the geometry of the junction and the continuity of …
The paradox of geometry
Following the procedure in TGD L, the energy performance of the proposed dwelling is not assessed in absolute terms of energy consumption, but measured against a Reference Dwelling with the same geometry of our proposal and basic specs that comply with 2005 standards. The required 60% reduction on energy performance …
