Measuring for an Outside Mount
Outside-mount shutters sit on the face around the window, so you measure the area the frame will cover instead of only the internal recess.
Measuring for an Outside Mount
Outside-mount shutters are fitted around the window opening instead of inside the recess. The correct measuring points depend on whether the window is square-set, has an architrave, incorporates a sill, or combines an architrave and sill.
The applicable outside-mount instructions below typically use the largest of the three dimensions so the opening is fully covered.
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 with an Architrave
Most windows will feature an architrave, as such this is the most common way to measure your outside mount shutter. Use the architrave itself as the dimension boundary.
- Measure height from outer architrave edge to outer architrave edge in three places.
- Measure width from outer architrave edge to outer architrave edge in three places.
- Use the largest width and largest height.
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.
Measuring Outside Mount for a Window with a Sill and Architrave
The lower height dimension begins at the top of the sill, while the top and side dimensions follow the outer edges of the architrave.
- Measure height in three places from the sill to the upper architrave edge.
- Measure width in three places from outer architrave edge to outer architrave edge.
- Use the largest width and largest height.
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