Insulation

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thamesside
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Insulation

Post by thamesside »

Just had a sloping lean to fitted. I need to insulate between the rafters then cover with T&G.

I intend on using a rigid insulation but if I need insulation 7cm deep do I fill the entire space with 7cm thick boards or do I leave a gap for air circulation ie. buy thinner boards?

Also do I push the boards to the plywood roof or should they be the T&G side flush for air flow behind them between the insulation and ply roof?

Oh, and do I need to metal insulation tape between insulation boards?

Thank you
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fin
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Insulation

Post by fin »

normally insulate between the rafter with say 100mm pir and then underneath with i think.....50 or 60mm straight across then plasterboard.

you also need to make sure its all installed correctly and all that.

is there any lights that need to be installed? id normally batten out the underside to suit the plasterboards and youve a void for wiring etc then also.

be loads of videos on youtube regarding this
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thamesside
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Insulation

Post by thamesside »

Do I fill the entire board between rafters or leave a space between the foam part and the bottom of the roof where the plywood is? He said I needed a gap there to allow air flow.
thamesside
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Insulation

Post by thamesside »

Do I fill the entire board between rafters or leave a space between the foam part and the bottom of the roof where the plywood is? He said I needed a gap there to allow air flow.
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