Thanks to the latest document from DCLG in the shape of the Part L 2013 Impact Assessment the mists of confusion around the policy are starting to clear, a little.

Existing dwellings, for example, have been completely ignored by the policy.

We already knew that consequential improvements and the 120 million tonnes of CO2 savings the policy could have delivered had been ditched.

We now know that no standards for existing dwellings have been improved at all.

Given that existing domestic dwellings contributes over a quarter of the UK’s CO2 emissions, this seems rather surprising. It leaves a lot for Green Deal and ECO to deliver and those polices have not exactly been racing out of the starting blocks.

For new build we are given more of a clue on what ‘FEES’ (Fabric Energy Efficiency Standard) may actually look like.

‘Broadly in line with FEES plus efficient services’ is the statement. It all depends on what a Government definition of ‘broadly’ actually means. Given ‘late spring’ was deep into the summer, your guess is as good as mine.

However, if we look at the Zero Carbon Hub work on a detached house this equates to something like U-values of:

 Wall   = 0.15 to 0.18 W/m2K

Floor  = 0.13 to 0.15 W/m2K

Roof  = 0.11 to 0.13 W/m2K

In reality of course, with the transitional provisions for Part L 2013, no building to FEES will take place until after April 2015.

If FEES is key to delivery of Zero Carbon Homes in 2016, this leaves little time for developers or manufacturers to get experience of building or innovating to this new fabric standard.

Not surprisingly, this Assessment doesn’t really seem to mention the consequences of the Government delay in responding to the consultation. It is a very real impact of Part L 2013 and one that we can but hope is not repeated for Part L 2015/16/17/18*

(*delete as appropriate)