Measuring Specialty-Shaped Storm Windows
Arched and angled windows are the hardest to measure and the least forgiving. Here is why, what to record, and how we review your measurements.
Why shaped windows are different
No second chances
A shaped window is made for one opening. A small error in a curve or an angle means it will not fit, and there is no standard size to fall back on.
More than two numbers
A rectangle needs a width and a height. An arch also needs its springline, and a trapezoid needs both side heights and a diagonal.
Openings are rarely perfect
Older openings can be out of square or uneven. Photos and a record of where each reading was taken help show what is really there.
What to record for each shape
Arch top
Straight sides that turn into a curved arch. You record the bottom width, the total height and the springline height, where the straight side becomes curved.
Round top
A continuous curved top. You record the bottom width and the center rise, from the bottom center to the highest point.
Trapezoid
A sloped opening with unequal side heights. You record the bottom width, the left and right side heights and the corner-to-corner diagonal.
How to capture it
These are the same steps as in our measuring guide.
- 1
Photograph the entire opening straight-on.
- 2
Record the maximum overall width and height.
- 3
Record every straight side, spring line, angled corner and diagonal shown on the shape diagram in our measuring guide.
- 4
Take a close-up photo of the mounting surface, and one with the tape visible.
- 5
Add notes on the shape, uneven trim and obstructions, and where each measurement was taken.
- 6
Send the photos and measurements to us for review before you order.
How our review works
Shaped windows are never ordered from width and height alone. You send the photos and measurements, and every dimension and photo is reviewed and approved before the window is made.
The measuring guide builds a record of your readings that you can send to us in one step. If you are unsure about the mounting surface, stop and send us photos before ordering.
Contractors and other pros who struggle to source or measure shaped windows are welcome to send their measurements for review as well.
FAQs
Can I order an arched or other shaped storm window from width and height alone?
No. Arch tops, round tops, trapezoids and other irregular shapes are reviewed before they are made. You photograph the whole opening, record the dimensions shown on the shape diagram in our measuring guide, and send them to us for review.
What shapes do you make?
Our measuring guide covers arch-top, round-top and trapezoid windows. Other irregular shapes can be sent in for review.
Why do you review specialty measurements?
A shaped window is made for a single opening and cannot be reused elsewhere, so every dimension and photo is checked before it is approved for production.
What photos do I need?
A straight-on photo of the whole opening, a close-up of the mounting surface, a photo with the tape marks visible, and photos showing handles, locks, trim and any obstructions.
I am a contractor. Can I send my measurements for review?
Yes. Professionals can send their measurements and photos for review before ordering. Use the contractor application to get started, or contact us with the project details.
What if my opening is out of square or uneven?
Record every reading where you took it, note any uneven trim in the shape and opening notes, and add photos with the tape visible. That detail helps us see the real opening when we review it.
Does the review change how long my order takes?
The review happens before production, so it adds a step. We confirm lead times for your order once the measurements are approved.
Start with the guide
Choose your shape and record each dimension.