Part L confusion

[boudlo]

Hi all

I'm having my small Victorian end terrace house re-roofed by a local contractor. I am aware that the work needs approval from the building control people and the contractor has informed them, paid the fee's, etc

Had a phone call from the contractor last week saying that in order to meet the Part L insulation standards, he would need to fit '50mm celutex between the rafters' at a [considerable] extra cost.

I don't know if the contractor and the building reg's guys have been talking at cross purposes, but I was under the impression that if I increased the ceiling insulation to 300mm it would meet the new requirements. Surely I don't need to upgrade the ceiling insulation and have this 'celutex' fitted as well? Wouldn't that reduce ventilation in the loft space?

The loft is a normal, uninhabited roof space with perhaps 100mm of insulation at the moment and not boarded.

I shall have to sort this out next week and would welcome your thoughts.

 

[freddiemercurystwin]

You're right, if there is no accommodation in the loft space then all of the insulation needs to be at ceiling level not at rafter level. Your builder is either a bit thick or trying it on. So the normal three layers of fibreglass roll stuff cross laid at ceiling level will be fine.

 

[boudlo]

Thanks for that, I thought it was a bit over the top!