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Insulating between the joists, and above the ceiling

2 Posts
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Posts: 1
Topic starter


I recently moved to an old property, which has previously had a room in the roof type conversion with stud walls and chipboard flooring. 

the entire loft is uninsulated, with nothing under the floor boards, behind the stud walls, or above/between/below the rafters. This is a concern as we move into winter and the temperatures start to drop. I am looking to add some insulation, and was wondering if it would be possible to remove the floor boards and use SteicoFLEX between the joists, directly onto the ceilings below? 

i have read that the depth of loft insulation needs to be at least 270mm, regardless of material. Is that correct? Would 270mm of the SteicoFLEX provide sufficient insulation? If not, what depth would you recommend?

I’m keen to avoid insulating between the rafters as it will require the removal of the existing plasterboard and stud walls and building up the depth of the rafters. We don’t have any immediate plans to use the room beyond storage.

Insulating between the joists seems like the simplest option as there is sufficient depth and this would only require lifting the floor boards. 

any advice would be greatly appreciated. 

Posted : 13/10/2022 11:52 am
Posts: 80
Member Admin

Hi Joe

Yes, 270mm of SteicoFlex 036 would easily be enough for your loft insulation and if you don't need to heat the space in the attic then it would be OK to install the insulation in this location.I would however suggest that you ventilate the attic room lightly to ensure that you do not get condensation building up in there with subsequent mould growth issues.

Hope that helps.

Posted : 17/10/2022 8:44 am

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