Advice sought please.

[ChedderAndChive]

Hi,

Im in a bit of a dilema where I have done some work but didnt notify LABC.

The work entailed romoving plasterboard ceilings and upgrading the insulation between the joists (some beneath a flat roof dormer). The problem is that the joists/trusses are only 75mm and so ive fitted 50mm Celotex and left a 25mm air gap which is not ideal but its better than no insulation at all. The ceilings are very low already so fitting beneath the joists is not somthing i really want to do. The work is about 75% complete. I have just been informed that removal of ceiling is notifiable.

So the question is do I tell building control and do it by the book, what will happen with regards to work already started.

 

[tony1851]

If you've left a 1" gap, that should be ok if there is breathable felt (or no felt) under the battens.
If there is the older bitumen-based felt, you ideally need a 2" air gap, and an inspector could well insist on that.
If it's mostly done, I'd keep quiet; so long as there is reasonable ventilation at eaves and ridge, you should be OK.

 

[ChedderAndChive]

Thank you for the reply.

OK I should have been clearer I have left a 25mm gap under the flat roof dormer section with 50mm of Celotex but I am considering converting this roof to sloping in a couple of years. Where I have sloping ceilings the rafters are 100mm and I have used 50mm Celotex leaving a 50mm air gap. The felt is the older type. I have no ridge vents at all just vented eaves although the dormer roofs are about 1000mm down from the ridge would this cancel the need for ridge vents?

 

[tony1851]

Hard to say without knowing the details of construction. The ideal in 'cold' roofs is to ensure that the space above the insulant is adequately vented to prevent any moisture from below condensing.
If it can't be completely vented, the next best opeion would be to try and stop moisture vapour from getting up there in the first place. The board is foil-faced, so if you could tape up all joints, that would help, and also even consider foil-backed plasterboard, though if you've already done most of it...?
From what you say,though, I doubt there is much condensation risk.

 

[ChedderAndChive]

Luckily I have foil taped all the joints. I think im just a bit worried not informing LABC, what are the likely consequences if im found to not comply with regs.

 

[tony1851]

They won't put you in jail or transport you to the penal colonies, but strictly speaking it is an offence not to inform Building Control.
However, in practice these things are dealt with informally. You can apply for a Regularization certificate, in which case the inspector checks the work to see if it complies; if in his opinion it does, you get your cert. If it doesn't, he will require you to do whatever necessary to make it comply.
It's expensive (its the standard fee x 2.25) so assume around £400, though thats only a ball-park figure.
But why bother? Have you told all the neighbours what you're doing? Have you put a banner outside your house stating that you're doing unauthorized work?
Who's to know? Why open a can of worms? Let sleeping dogs lie IMO.

 

[ChedderAndChive]

They won't put you in jail or transport you to the penal colonies.

OK thanks for the reply, I think im just going to finish what ive started and say no more. 50mm of Celotex has got to be better than non.