Window operation comparison
| Type | How it opens | What to check |
|---|---|---|
| Casement | A sash swings on hinges. | Sash travel, hardware operation and space in the well. |
| Sliding | A sash moves sideways. | The usable opening with the sash fully open. |
| Single- or double-hung | A sash moves vertically. | Usable opening, operating effort and the proposed installed height. |
No operation type automatically establishes compliance. Compare the exact model and installation.
Well materials and shape
Wells are available in different materials and configurations. Ask about resistance to deterioration, attachment to the foundation, usable interior space, access features and replacement parts. Confirm that the proposed well fits the excavation, window movement and applicable requirements.
Cover and access choices
Compare a cover’s fit, attachment, interior release and maintenance access. Ask for product documentation for any claimed load rating. Review the well, cover, steps or ladder and window together before purchase.
Request a complete product schedule
Ask for window, well and cover model names in the quote, together with drainage details. A written substitution should explain any effect on opening size, operation, appearance or warranty. This makes competing quotes easier to compare.