What to use to seal gaps around windows?

[Samantha L]

Hi everyone. Looking for advice on what to use to close the gaps between UPVC windows (I know!) and Cotswold stone. Currently there is clear silicone which is coming off and there are lots of gaps where water and bugs are entering. What’s the most appropriate product to use on this inappropriate windows? Thanks!

 

[fernicarry]

It'd probably be a good idea to point up the gaps in the stonework first to give you a smoother surface to seal against.

 

[Jahouli]

I've had good results with this: https://www.sealantsonline.co.uk/Pr...-premium-natural-stone-external-silicone-matt.
Look for something that clearly states its suitable for stone and UPVC. I think its worth paying for something of better quality that should hopefully withstand weathering for a little longer. Some products come in a range of colours, so it's easier blend with the stone.
When applying be sure to thoroughly dust off the stone to get good adhesion.

 

[Robola]

Is there a piece of wood in there behind the pointing? If so I would be removing that to allow for proper pointing repair.

 

[Cubist]

I suspect that you will need to remove all of that old silicon before you begin to apply any replacement material. Where the old has separated either from the masonry or the UPVC frame it will be nigh on impossible to achieve a good clean and effective seal. You will need either to pull all the old stuff out or, after cutting it away from edges of the UPVC, pushing it inside the frame to hide it or operate as a support/base for the new sealant. Typically I would recommend a burnt sand mastic for the new job but as the frame is UPVC then a silicon sealant would be the easiest and simplest solution.

 

[Samantha L]

Thanks all, so I think combining everyone’s advice the course of action will be.

1. Remove old silicone
2. Rake out old pointing and replace with new lime mortar
3. Re-silicone as is windows are UPVC

 

[Cubist]

@Samantha L .... I should have pointed out that you need to be careful when pushing any material, unwanted old silicon or even new lime mortar, into the gaps beside and behind the UPVC frame as it can be easily distorted.

 

[Samantha L]

@Samantha L .... I should have pointed out that you need to be careful when pushing any material, unwanted old silicon or even new lime mortar, into the gaps beside and behind the UPVC frame as it can be easily distorted.

Thanks very much, will do!