Acceptable tolerances for window frames

smokey5877 · Post by **smokey5877** » Fri Oct 12, 2018 11:22 am

I've recently had new timber windows fitted to a listed building. On the plans submitted for Listed Building Consent, the frames are listed as 50mm wide. What tolerance is acceptable based on the premise that the design is for those to be 50mm?

dewaltdisney · Post by **dewaltdisney** » Fri Oct 12, 2018 11:41 am

I would have thought that as a listed building these pedant planners should have specified imperial measurements not metric. You have an argument if they get silly that you were copying the original dimensions in inches

DWD

smokey5877 · Post by **smokey5877** » Fri Oct 12, 2018 11:47 am

smokey5877 · Post by **smokey5877** » Fri Oct 12, 2018 11:49 am

dewaltdisney wrote:I would have thought that as a listed building these pedant planners should have specified imperial measurements not metric. You have an argument if they get silly that you were copying the original dimensions in inches

DWD

It is only partly an issue with how the Council view it. I agreed the width to be 50mm, what would Joiners be happy with as a tolerance to be a "good job"? It is softwood and made in the workshop, not on site.

ayjay · Post by **ayjay** » Fri Oct 12, 2018 12:36 pm

It really depends on how it's worded. A normal view of a 50mm timber dimension on a drawing is that this is a nominal measurement and the finished size will be about 44/45mm, but if it says 50mm FS then it should be 50mm - FS = finished size.

Argyll · Post by **Argyll** » Fri Oct 12, 2018 12:40 pm

Falkirk building standards state -0mm/+2mm

I'm not sure what the regs are elsewhere.

smokey5877 · Post by **smokey5877** » Fri Oct 12, 2018 12:45 pm

thanks all.

I've measured my window and the frame width is 56-57 mm when it should be 50mm. I just wanted to know if the fitter is blagging when he says 57 mm is within joiners tolerance. I see NHBC regs are much tighter, and the figure I seem to be getting back is 5mm tolerance maximum. The window is only 900 mm x 900 mm so I'd have thought things would be more accurate.

ayjay · Post by **ayjay** » Fri Oct 12, 2018 1:19 pm

They've probably used the nearest stock size that they had available - at a guess, a nominal 2.5" which when prepared will come down to 2.25" or 56/57mm.

smokey5877 · Post by **smokey5877** » Fri Oct 12, 2018 1:34 pm

Seems very odd, as the same people did 5 other windows in the summer all 50mm or there abouts.

wine~o · Post by **wine~o** » Fri Oct 12, 2018 5:47 pm

Are the people from the listed building consent office happy with it ?? If so not a problem...

Acceptable tolerances for window frames

Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames

Re: Acceptable tolerances for window frames