You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
It’s been pointed out to me there is about a 15mm wide gap under the external window sill and the pvc window in our bay, what’s the best way to seal it to help keep it a bit warmer? It’s deep so sealant is probably out as it would take loads of tubes, bay is approx 5 metres,
Expanding foam? Or mix up some cement? It’s quite deep, approx 40mm
I'd use foam (and have). It's exactly what it was designed for. Cement will likely shirink and you'll end up putting mastic in anyway.
Mask it off before you start. It gets everywhere, particularly on the brickwork below. Let it dry over 24hrs then use an old steak knife to trim it back. Render with whatever you like.
Yep - external (ie waterproof) expanding foam. As above - squirt it in, leave to dry, cut to desired shape and then finish.
NB If it does over flow and start dripping everywhere just leave it. Much easier to clean up once it's dry than to try and wipe when wet, which just smears it everywhere...
dry
{Pedantic mode on}
Cured
{Pedantic mode off}
wet
{Pedantic mode on}
Uncured
{Pedantic mode off}