Just about to paint some window lintels and reveals but wondering how best to prepare the corners where the uPVC frames meet the masonry - presume there's some sealant underneath and the paint is cracked/peeling on top (see picture). What's best here?
Thanks
E.
Scrape the corner with a shavehook and run a bead of decorators caulk? Unlike silicon, the caulk can be painted over.
Thanks - do you mean strip out all the existing sealant with the hook and redo it it all? Or just caulk over what's not flaking?
E.
I would remove as much existing sealant as possible and make sure there is no damp visible.
Caulk is not generally suitable for external use but there are sealants that that are eg:
It may be that the existing sealant is in good condition but it is silicone based and so did not take the paint well. If that is the case I would rub off the loose stuff with a plastic pan scrub and either:
Paint over again, knowing that it will take a while before the paint over silicone breaks up again or
Run a smear of the Polysulphide sealant above over the existing silicone and then paint over that after it goes off (which can take a while).
The latter will also work if there are cracks in the original sealant.
Mask the frame with PVC tape before scrubbing to protect the finish and again to control the spread of sealant and then again the paint. Removing the tape immediately after applying the sealant will leave a clean, sharp edge.
My thoughts are that using sharp tools risks simply tearing the silicone, making more of a mess.
In article , Bod writes
Yes, that example is but generally they are not.
Of the 6 examples on the TS caulks page, only one specifically states that it is suitable for exterior use.
Decorators' caulk (TM) is _generally_ cheap s*it, full of cheap inert filler that makes it inferior to and less flexible than dedicated sealants. I'd expect the true sealant to adhere better to the existing base in the thin film application of the o/p's example too.
Examples of where I would use a caulk externally would be in a sheltered location, not subject to driving rain, and where I was starting from scratch and the product could get a good key into an existing gap. It should always be painted to seal the surface whereas sealant can be left in self colour if desired.
I'cve never found caulk good for anything much, inside our out.
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