Old Loft insulation above rafters

Postby Ag1 » Wed Jan 01, 2014 9:58 am

Hi we have a three bed detached 1960s wimpey house. When we moved in we noticed there was strips of glass fibre insulation running gable to gable above the rafters. The insulation is fused with the felt above. Bizarre! There was also old gf insulation between the ceiling joists about 50mm. When we first moved in there was condensation in the rafter insulation and a musty smell however this has improved greatly after pulling the joist insulation away from being tight to the eave and by topping up the insulation between the joists and on the hatch. I'm looking to improve further by putting in soffit vents and a proper bathroom extractor fan.

I now want to protect the stored items and people who go into the loft from disturbing and getting covered in the insulation in the rafters and I'm unsure which material to use to cover the insulation in the rafters? Should it be a polythene sheet which would act as a vapour barrier or something breathable such as fine garden mesh or even plantex membrane? Whichever I used I would leave a gap top and bottom. For further background I will be putting in raised chipboard flooring for the storage. Any advice on covering the rafter insulation greatly appreciated. Thanks Adam
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Simply Build It

Postby welsh brickie » Tue Jan 07, 2014 4:07 pm

if your going to cover the area with loft boarding, then just use that, the weight will compress it 50mm and then screw it down to the ceiling joists,
as for the insulation between the rafters??? I would remove it to increase airflow
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