DIY Doctor UK DIY Forums

Hello,

I live in a dormer bungalow where a storage room in the upstairs part does not have adequate insulation. I need to fit celotex boards between the rafters and also some sort of insulation under the floor. Looking under the loft floorboard, there is just a big gap where i can see the ceiling of the kitchen below and the light fittings.

I've had no luck trying to get a specialist company to come out, so going to have to do it myself. Not 100% on what to do though.

For the roof part, I think I can fit celotex board snugly between the rafters. I just need to make sure there is at least a 5mm gap between roof felt and board to allow for air flow?

What about the gable wall? That is bare brick at the moment, but I guess in theory it should have cavity wall insulation inside it?

What is the best way to approach the floor insulation? Should I get up the loft floorboards, fit some sort of net below them and then hang the insulation in the net? Kind of like how underfloor insulation goes? I can't just put insulation in the space as it would be touching the kitchen light fittings below and I'm not sure if the kitchen ceiling would take the weight either. It is like some very thin board with artex on.

Appreciate any help with this as I'm very concerned about the consequences of getting it wrong.

Thanks

Hi straygoat,
Unless you are going to make your loft space habitable there is little point in insulating the roof part/gable end as you propose.
Concentrate on insulating the ceiling, use standard loft insulation with guards around any ceiling lights. You could increase the depth of insulating by fitting extra rafters on top of the existing ones.
Regards S

Hi

Thanks - most of the loft space is habitable already. It is just one section that is used for storage that needs to be insulated (must be compromising the insulation of the upstairs as a whole).

What's the best way to get the insulation held in place in the ceiling? I don't think the ceiling is strong enough to cope with the weight of loft insulation on it.