Working with an architect on a glazed extension
The best projects have the glazing specialist involved before the drawings are finalised. What to draw, what to settle early, and why lead times catch people out.
- Bring the glazing supplier in at design stage, not at tender.
- Frame sizes, head heights and sightlines should be drawn, not assumed.
- Structure, drainage and setting out drive the price more than the glass does.
On a good glazed project the architect and the glazing supplier are talking before the drawings are finalised. On an awkward one they meet for the first time at tender, when the opening has already been drawn and priced.
Bring the supplier in early
A glazing specialist will tell you what the frame can do at a given size, which head height is realistic, where the structure needs to sit and how the threshold will drain. That information changes the drawings, and it is far cheaper to change a drawing than a building.
What to draw
Frame dimensions, sightlines, opening direction, stacking positions and the location of fixed panels should all appear on the elevation. So should the head and base details at full size.
Ambiguity here is what causes a variation later. A door that arrives with a frame 50mm wider than the opening is a drawing problem rather than a manufacturing one.
Structure, drainage and setting out
The structural opening decides everything downstream. If a steel beam sets the head height, the frame has to suit it rather than the other way round. Drainage has to be designed with the groundworks, because the finished floor levels on both sides of the threshold are what the detail is built from.
Lead times
Bespoke systems are manufactured to order after a site survey, and lead times run into weeks. The glazing should be surveyed and ordered as early as the build allows, not at the point the walls are finished.
Written by the Minimal Frame Projects UK team. If you would like advice on a specific opening, send us the dimensions and a few photographs and we will come back with a specification.
