What are some reasons an upstairs floor in a new house would be angular? (floors, roof)

[potatosoup]

I'm looking at a house that is less than 20 years old, and all the floors throughout are even as far as I can tell. However one floor upstairs seems to be somewhat angular, so that if you dropped a marble on it, it would slowly role towards the other end.

The house did have several additions put on, one near this wing of the house. Is a home inspection enough (from someone who is a building engineer) to determine whether there is a serious issue? Or is this typically normal from a house that settles over time?

[mrs1885]

Wish I could help. Our house doesn't have a single level floor or straight wall anywhere. We've just kind of gotten used to it. *shrug*

[Charles22]

It was probably built on top of an existing roof. This is before they invented the bubble level.

[potatosoup]

Originally Posted by Charles22

It was probably built on top of an existing roof. This is before they invented the bubble level.

My understanding is that it was part of the original house. The additions were adjacent to this room (and downstairs).

[mawipafl]

It could be that it's always been that way or perhaps when the house settled, it just settled a little bit more on that end. Or it could be a structural problem that an inspector would be able to see right away if there's any separating happening where the ceiling and wall meet or where the wall and floor meet, or if there any major cracks around doors and windows. He'll look not only at that second floor, but also in the attic space above at the joists and rafters and the roof, on the first floor beneath as well as whatever is under the house on that side (basement or crawl space) and the foundation.

It may be that when the addition was put on, the ground was disturbed enough to affect the settling of the house on that side although I would think the first floor would have been affected, too, which it appears it wasn't.

Is the addition attached to the main house directly below that second floor room? If so, and presuming the addition's roof is attached to the main house at the second story floor level, its weight and settling may have initially "pulled down" on that part of the main house. Again, an inspector can look at the structural elements of the addition and see if there are any issues.

As a layman, you can visually inspect these areas yourself, looking for glaring problems such as warping or cracks or separations. These things are quite evident to an untrained eye even if previous owners have tried to mask or repair them. I wouldn't rely solely on a self-inspection, but if no red flags go up for you, chances are that the angled floor is just an "oddity" of that house and won't be a problem.