Hi,
I've checked out previous posts on uk.d-i-y but I'm still a bit unclear. The original mortar sealing around my window frames (original c.1900 sash and bay windows) has cracked and fallen out in several places, so I have removed the mortar as part of overhauling the windows.
Looking through various posts, some people are advocating using frame sealant, others recommend using mortar, whilst some suggest using a combination. What should I be using for my windows?
Thanks,
Steve.
There shouldn't be too much space between the frame and the brickwork as the outside lining is part of a box that holds a sliding mechanism and space is a premium.
You may find silicon effective but if there is a larger than normal space mortar is the more effective filler.
I'm just completing more or less the same process. I ended up with a gap between the brickwork and the frame that varies between about 7 to 10mm. What I did was to fill this with mortar (1:4.5 masonry cement:sand) using a dry mixture (to avoid it flowing out of the 6 ft verticals and the upside-down bit at the top) and a pointing trowel. This mix is (supposedly) equivalent to the 1:1:6 OPC:lime:sand mix usually suggested.
If it eventually shrinks back and opens a crack between the window and the mortar, I'll follow up with a bead of frame sealant.
However, the problem I have is that a hairline crack has opened between the new mortar and the brickwork in some areas. Is this because I was using a dry mixture over the hot weekend and it's dried out too quickly ? Is there anything I can do about this apart from chisel it out and try again ? Sealant wouldn't look right here.
Cheers,
Phil Young
Hi,
I'd stick a strip of wood/foam etc round the frame that goes 5mm deeper than the surface of the brick. Then when the cement dries remove it to leave a 5mm deep channel, put a strip of PVC at the bottom then fill with sealant to create an expansion joint.
A wood/uPVC frame will move with humidity/temperature so cement alone will never give a good seal.
cheers, Pete.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.