The proper way to install windows on the house that is not level

levelwindows

My house is sloped at least 1/8" per 1' along the front side. It also has long horizontal siding. So if windows are installed level it may be pretty noticeable. Leveling the house is not an option. So I wonder how can I minimize visual effect of the difference in levels between house and windows.

Should windows be installed parallel to the siding (and be out of level like old ones) or should they be exactly level (and what do I do to minimize visual effect)? Or should they be installed lets say with 1/16 angle – is it still ok?

Best Answer

Installing opening windows out of plumb (out of level), will make them hard to open and close, and may affect their ability to seal well. If the windows are fixed, this is less of a problem.

If you install them level, the most noticeable issue will be the top and bottom, probably not the sides. You can address this by being creative with casings, the molding around the windows. If you put a shallow triangular pediment across the top, it will mask the angle difference between the window and siding.

triangle

An alternative is a curved facia board at the top, or any other combination that breaks up the horizontal line.

The bottom could be handled similarly, but there is less tradition of decorative moldings or pediments at the bottom of things. A straight, stepped molding might also break it up.

stepped molding

SUPPLEMENT: Based on the additional information, 1/8" in one foot is not a lot of lean. I would still hang them plumb and mask it with the moldings. You could rip cut the molding on a slight angle to split the difference. Also, having the moldings NOT end at the edge of a siding board makes variances harder to notice.

window trimmed