I am about to fix a external upvc cill & window for my garage window.I have read that you can either cement cill into place or use a few beads of mastic ,which seems a better idea.
Any ideas as to what you can use ? would it be something like gripfill,no nails, silicon or something similar which would set hard after a while.
I have over the years just used silicone sealant purchased from local store,now closed after 27 years to re-seal around my house upvc windows .I decided to see what if any silicone sealant is superior.As mentioned somewhere on forum the Low Modulus Silicone Neutral Cure seems to be best as it sticks to brickwork & frame better.
However they do say it is dearer than normal High Modulus silicon.Had a look in the Wicks book but no mention of if any of their silicone sealants are high or low and indeed if any one is suited for upvc windows.
I then went to the Screwfix web page and they do sell a Low Modulus Silicone but at only £2.69 a tube.That has thrown me a bit.Has anyone used this Screwfix silicone or recommend a silicone from either shed that would be suitable but good.