Obviously, unleveled floors are characterized by, well, non-level or sloping floors. However, floor sloping may be a sign of an underlying structural problem.
If your floor is unlevel, check out the following characteristics which could clue you in to your particular sloping floor’s underlying cause and, consequently, give you an idea about the cost of repairs.
Direction and Nature of Slope
Sloping in One Direction
If your floor is significantly sloped towards one direction, this could be an indication of structural damage such as foundation damage or settlement. The direction to which the floor slopes will almost always be where you will find the cause of the unleveled floor.
This type of condition is also oftentimes accompanied by other symptoms aside from sloping floors. Such symptoms are cracked foundations as well as cracks in the wall plaster and walls (especially near doors and window frames).
Unleveled Floors in Certain Parts of the House
Localized slopes in floors or sloping limited to certain areas of the house typically indicates damage to such areas’ supporting members (e.g., girders, joists or supporting posts). This type of damage is usually cheaper to repair than the one mentioned above.
A common example of this type of problem is sloping localized to the fireplace built on a central area. What usually happens in this case is that the fireplace structure was installed over ground that had not been compacted as much as the ground where the foundations were built. It could also be that the central structure’s foundations were not built as deeply as the perimeter foundations of the house.
Whatever building mistake was committed initially, the end result would be the same: settlement in the central area. Since the house’s girders and joists are naturally connected to the structure in this area (the fireplace, in our example), any settlement in this central area will naturally lead to a sloping of the floors around it.
Vertical Location of Floor Slope
Sloping Floors in the First Story
If floor sloping is limited to the first story of the house (that is, there is no corresponding slope to the 2nd-story floor), then the reason could be missing support posts and damaged joists.
However, if the second floor slopes along with the first floor, then there could be a more serious structural cause such as foundation damage or settlement.
Sloping Floors in the Second Story
If floor sloping is limited to the second story of the house (that is, there is no corresponding slope to the 1st-story floor), then the reason could be damage to the beams or joists that are holding up or supporting the floor of the second level.
This usually happens when second-story floor joists are merely nailed to the side of a 2×4 extending from the first floor to the roof supports of the second floor. Other possible causes are undersized beams, beams that are not not properly located for load-bearing, and termite damage to the wood.
Issues with Walls, Doors and Windows
Since the frames of door and windows are connected to the floor, floor sloping also affects these elements because they adjust to the sloping of the floors. This “adjustment” is manifested in the cracking of the wall plaster, the sticking of doors and windows (when they didn’t stick at all before), the loosening of the nails in walls and ceilings, and the appearance of gaps in doors and window trims, etc.
Damage to the Structural Elements of House
To determine if damage to structural members is the underlying cause of your sloping floors, your basement or crawlspace will have to be inspected for the following:
i) Rotting, sagging or damaged floor joists,
ii) Rotting, sagging or damaged girders,
iii) Rotting or damaged sill plates,
iv) Rotting or damaged cripple wall studs,
v) Cracked or crumbling foundation, and
vi) Cracked, crumbling or damaged posts.
To check the above components, a standard ocular inspection of the perimeter and the first and/or second stories of your house is not enough. There should also be an inspection of and a report on the state of your home’s crawlspace or basement, perimeter foundations, under-floor elements [there may be a need to remove some floor boards for this], etc.
It is important that you get a floor leveling inspector with foundation repair expertise if a thorough inspection of your house’s structure is to be made. This way, you can be assured that the repairs you will pay for will be effective in the long-term.
Floor leveling can be very expensive. Fixing a sloping floor (and addressing the underlying structural damage, if any) can actually lead to a need for other repair work such as wall crack repair, floor reinstallation, and wall plaster repair, among others. To save money, therefore, make sure that repairs are done right the FIRST time. Otherwise, costs will pile up as you will need to pay for even more repairs.