Measuring Bay windows

13 Nov 2006
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United Kingdom
:D I am currently trying to work out how to measure a bay window for replacement upvc windows,, the bay doesn't have any brick piers, it is just a continuation. is there anyway I can measure it without purchasing a winkle "thing" for £95, all help would be gratefully appreciated
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Do you mean something like this one ?


I measured the Width, Height, and then gave them a measurement i would like it to protrude. If you want it to stick out lets say 350mm then don't forget to tell them thats to the galss and NOT the windowsill as that sticks out another 100mm or so

You could end up with a near flat bay if you dont clarify that.
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First you need to draw out the bay as you require it then go outside and measure the height from under the sill to the top of the head if you can see the top of the existing frame this is perfect, but you may have to remove any cover bead to reveal this

Next go inside fix a string line to the left hand frame with a nail then take it across the bay to the right side and fix on the frame edge, measure the width this way then measure to all the inside angles of the existing frames from the taught stringline

then also measure all the internal frame widths from angle to angle and add them to your drawing shown from an above view.

When ordering remeber to state you require a welded sill and all bay poles, if the bay is supporting you will need to state this so the poles can run through the sill onto the brickwork

If when ordering your measurements are for some reason way out this should be picked up by the programme the window company uses.

Remeber to duduct about 10mm from the overall width and height to allow for expansion, and when fitting if its a supporting bay use acrows before removing the old one

Good Luck

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