Window frame filler?

[Patrick254]

Some of the seals around my timber window frames are falling apart but I'm unsure what materials to use... Looks like the original builders have mixed sand or grit into something and packed it in. Could I just use caulk? Any advice much appreciated!

 

[Deleted member 174758]

That is probably traditional trowelling mastic and not something mixed by the builders on the spot

 

[Patrick254]

That is probably traditional trowelling mastic and not something mixed by the builders on the spot

Oh brilliant, that's really helpful thanks!

 

[Deleted member 174758]

Rake out the old stuff with an old chisel, putty knife, hacking knife or the like. New trowelling mastic comes in a variety of colours can be had from any builders merchants. You'll need a tuck pointer (or an old bent knife - straight blade) and a small mortar board (piece of 6mm ply or MDF about 150mm square screwed to a length of broom handle) to replace it. Best to redo the lot as once it starts to crack it all tends to go eventually

 

[crank39]

Sounds like burnt sand mastic