Hi, just wondering if anyone can help me with this.
I have just had new UPVC glazing fitted by a company, and wonder if someone can tell me how much gap should there be in new UPVC window installation. The windows are measured/fitted correctly widthwise, but, are short by approx 20-25mm - that is above the existing mortar bed, this means when filled the mortar bed will end up 35mm and look ridiculous. The company keep telling me this is standard, but, I have had windows installed in the past and never, ever, had a gap below them like this. After they initially patched the mortar up the majority cracked and dropped out. They are currently trying to convince me this is standard, and the windows should have this amount of gap below them, it just sounds rubbish to me. I don't know how they have managed to get the width right and make such a mess of measuring the height. Can anyon please advise. Many thanks.