How to Measure
A simple, fool-proof guide to measuring your opening so the product you configure arrives a perfect fit. All dimensions on Swift Frames Direct are given as Width × Height in millimetres.
Standard Windows
Measure brick-to-brick (the outside opening). Take 3 width readings — top, middle and bottom — and use the smallest. Do the same for the height. Then deduct 10mm from each to allow for fitting.
- Take 3 readings and use the smallest.
- Always quote in millimetres (mm).
- Allow 10mm on each side for fitting tolerance.
Entrance & Composite Doors
Measure the existing frame including the cill and threshold. Width is taken in 3 places (top, middle, bottom); height is measured both sides. Use the smallest reading and deduct 10mm.
- Take 3 readings and use the smallest.
- Always quote in millimetres (mm).
- Allow 10mm on each side for fitting tolerance.
French & Patio Doors
Measure the brickwork opening width at top, middle and bottom. For height, measure both jambs from the cill to the lintel. Side panels (if specified) are included in your overall width.
- Take 3 readings and use the smallest.
- Always quote in millimetres (mm).
- Allow 10mm on each side for fitting tolerance.
Aluminium Bifold Doors
Measure the structural opening width — bifolds need 10mm tolerance on each side. Height is taken from the finished floor to the underside of the lintel. Tell us which way the doors should fold/park.
- Take 3 readings and use the smallest.
- Always quote in millimetres (mm).
- Allow 10mm on each side for fitting tolerance.
Roof Lanterns & Skylights
Lanterns are measured as Width × Projection (often called Length) in millimetres. Measure the upstand on which the lantern will sit — outer to outer. Allow for the kerb height when calculating overall ceiling clearance.
- Take 3 readings and use the smallest.
- Always quote in millimetres (mm).
- Allow 10mm on each side for fitting tolerance.