Measure guide
Window well cover sizes
Stock 40×18 lids are what warehouse sites sell. Western Prince William wells are often a different shape. Measure the well you have — or photograph it and let the installer measure.
Why the catalog size misses
A D.R. Horton, Pulte, or Toll colonial in Gainesville, Haymarket, or Bristow may have a Wellcraft, Boman Kemp, or poured custom well. The opening is rarely a perfect 40-by-18 rectangle. The flange may be wide, the wall bowed, or the well a half-circle. A mail-order cover that “almost” fits leaves a gap for leaves and a lip that an HOA will see from the sidewalk.
Custom covers are cut to the well after a measure. That is the product this site is for. We do not sell a SKU from a warehouse aisle.
What to measure
If you want a useful first conversation, take three numbers and two photos. The installer will still measure before they fabricate.
| Take | How | Why it matters |
|---|---|---|
| Width | Outside of well to outside of well, along the foundation. | Sets the long dimension of the lid. |
| Projection | Foundation face out to the farthest point of the well. | Half-round and flared wells are deeper than they look from the yard. |
| Shape | Rectangle, half-round, bow, or “none of those.” | Tells the shop whether a stock blank even exists. |
| Lip / flange | Does the cover sit on a rim, in a track, or on the grass? | Low-profile vs. dome, and whether the old lid can be reused as a pattern. |
Write the numbers in inches. Do not convert to a product title you saw online. If the well is out of square, say so — clay soil and a settling yard in 20169 will do that.
What to photograph
- One wide shot: foundation, well, and a few feet of yard, so the installer sees grade and the window.
- One shot with a tape across the opening, numbers readable.
- The existing cover, if any — especially if it is yellowed, cracked, or screwed down.
- The inside of the well if you can do it safely: drain, rust, standing water, ladder.
This form does not upload files. Describe the photos in the quote notes; the installer can take them by text on the callback.
DIY vs. measured
A $40 rectangle can cover a standard metal well on a 1970s rambler. It is the wrong bet on a custom well beside a finished basement in Dominion Valley. Gaps collect leaves. A proud dome fails the curb test. And a cover that does not release from inside fails the egress rule even if the tape measure was close.