Pitched Roof Void Insulation

[Corry]

Hi -

Looking for a some help. I've found my pitched roof has no insulation in it. 

When I insulate it would you lay a few layers of rock wool and leave the RSJ.

Or does the RSJ require separate and more thorough insulation. That litlle bit of insulation just fell through.

Any advice appreciated. 

 

Cheers.

[ProDave]

That looks like a fairly recent build.  It would be unusual not to have any insulation.  Are you sure that is not a warm roof? is that "board" I am seeing over the rafters something like kingspan or similar insulation sheets?

[Mr Punter]

300mm mineral wool on the ceiling and if you have enough space, around and over the rsj/blockwork, otherwise Celotex around and over.

[Corry]

Hi

Thanks for the replies and help.

I'm not sure what a warm roof is but I don't think it is.

Cheers.

[A_L]

@Corry A warm roof is one where the insulation is wholly or partly above/outside the structural elements. It may be that there is no insulation because this area is notionally outside the heated space/volume and no insulation required. 

[ADLIan]

Have you a photo showing the front elevation of this bump out rather than the side. If only a porch and the main external door is between the house and this area then it’s probably outside the thermal envelope so no insulation required. However it looks to be too long for that and may well include part of a ground floor room ceiling in which it should be insulated with 300mm (min) of quilt insulation. Looks like they did try to prevent the thermal bridge across the steels by packing with insulation - not sure how successful that would be! Run more insulation vertically against wall to minimise thermal bridge through steel. Not sure how you would do this so late in the day, perhaps have to remove roof tiles. Is house still under any warranty?

[Corry]

Thanks very much for the help ?

 

Cheers.