Cleaning for mastic

[john4703]

Hi,
I saw a guy installing new uPVC windows and he used some sort of cleaner before he put mastic on to seal the edges.
My windows have the mastic peeling off on many places so I thought I'd take it all off, clean the frames and remastic.
I wondered what to use to get the uPVC clean so the mastic sticks and does not peel off and what is the best white mastic to use.

 

[Gazman16]

PVC solvent cleaner (type 32) you can get it in most big diy stores.
A couple of things to watch for though:
Firstly dont leave solvent on the frames for too long as it will eat into the finish. Work on one are at a time about the size of an opening sash and then go over it all with glass cleaner to clean it off.
Secondly solvent is great at getting off oils and grease etc but not so good at ground in dirt so its best to get them a good general clean (hot soapy water) before you use the solvent.

 

[crank39]

Solvent is only to be used on white frames as you didn't state your colour, DO NOT use on wood grain effect frames