what sealant is suitable for sealing gaps in ceilings/walls

batman1

Could someone tell me what sealant I should use for sealing around ceiling penetrations in the attic such as pipes, wires for lights and extractor fans. Also for sealing around window boards and along the base of skirting. It's all for sealing draughts.

kkelliher

batman1 wrote: »

Could someone tell me what sealant I should use for sealing around ceiling penetrations in the attic such as pipes, wires for lights and extractor fans. Also for sealing around window boards and along the base of skirting. It's all for sealing draughts.

In attics I would use an expanding foam (fire rated if required) and in most of the other senarios you would get away with a caulk as you will want to decorate it.

aujopimur

For narrow gaps (4/5mm), use painters caulk, for larger gaps use expanding foam finished with filler.

Joey the lips

Foam is brilliant. Sound stupid but use vasaline where you dont want it to stick ie just beyond the boundry of the sticking. Foam is very very messy.

MicktheMan

batman1 wrote: »

Could someone tell me what sealant I should use for sealing around ceiling penetrations in the attic such as pipes, wires for lights and extractor fans. Also for sealing around window boards and along the base of skirting. It's all for sealing draughts.

For a long lasting result use proprietry air tightness tapes, membrane strips and mastic which have been developed to do exactly this.
In my experience most expanding foams are not airtight after a time.

Joey the lips

MicktheMan wrote: »

For a long lasting result use proprietry air tightness tapes, membrane strips and mastic which have been developed to do exactly this.
In my experience most expanding foams are not airtight after a time.

Your not doing it right so. Foams problem is not its ability to stick and seal but its mess.

MicktheMan

Joey the lips wrote: »

Your not doing it right so. Foams problem is not its ability to stick and seal but its mess.

As an airtightness tester I can tell you that expanding foam is not airtight after a time. It may very well be for a while, but believe me it will deteriorate over time.
Take a short piece of 4" pipe, fill the inside with spray foam and leave it for say a year or two, then check if the foam has loosened and come away from the piping.

batman1

All I want to do is seal around where lights are fitted in the ceilings and where plumbing pipes come through the ceiling, all done from the attic while I'm upgrading the insulation up there. I thought a brand of some sort of mastic sealant would suffice. There's only 4 or 5.

MicktheMan

For a long lasting solution use air tightness tape. I use *iga products (Sounds like Liga) which allow for differential movement of differing materials over time.

paddy147

batman1 wrote: »

All I want to do is seal around where lights are fitted in the ceilings and where plumbing pipes come through the ceiling, all done from the attic while I'm upgrading the insulation up there. I thought a brand of some sort of mastic sealant would suffice. There's only 4 or 5.

I wouldnt do that if I were you.


What if you need to change a light fitting in the future and you need to pull some slack down from the ceiling for new light fitting.

You would also need the sealent/expanding foam to be fire retardant too.....lights and electricity.