Sealing round new double glazed windows

1 Apr 2009
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United Kingdom

We've just had some new double glazing windows fitted and they look great. They have sealed the left, top and right of the windows with brown sealant but, under the upvc window sill, if you get your head down there and look up, there's a bout a 2-3 mm gap between the bottom of the sill and the brickwork. It's not big, but it's a gap. One a couple of the windows, the sill is quite short as it sits on top of a stone window sill. Again there's a small gap and brown silicone may not look right, so maybe a thin silicone bead may resolve it?

Should this have been sealed? It's beneath the sill and not visible unless you get your head there, but I'm thinking about drafts, etc. and maybe moisture could get in there. I don't know. I just want to know if it should have been done

Any thoughts?

Many thanks.
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diychicken, Good evening.

Any chance you can post Images of the windows in general and close ups of the areas you are concerned about?

@KenGMac Here are two pictures. You'll see what I mean by the short sill as the stone sill is the "actual sill". I would be concerned that a big bead of brown mastik might be visible on the stone, unless it could be masked off somehow.



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