Outside Mount Measuring for a Square-Set Window
A square-set window has no separate architrave, so an outside-mounted shutter fixes directly to the wall face around the recess.
Measuring Outside Mount for a Square-Set Window
A Square-Set window is an opening without a timber frame (Architrave).
Measure from the inside edges of the opening; the needed shutter frame allowance can then be applied around the opening.
- Measure the drop in three places.
- Measure the width in three places.
- Use the largest width and largest drop
If you don’t have a protruding window sill: add 42mm to each side — 84mm total to the width and 84mm total to the drop.
Where the opening has a protruding window sill: add 42mm to the left, right and top only — 84mm total to the width and 42mm total to the drop.
Measuring Outside Mount for a Window with a Sill
The height begins at the top surface of the sill.
- Measure height in three places from the sill to the upper reference point.
- Measure width in three places.
- Use the largest width and largest height.
For a protruding window sill: add 42mm to the left, right and top only — 84mm total to the width and 42mm total to the drop.
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