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acceptable slope of interior floors?

J

JPohling

SAWHORSE
Joined
Aug 16, 2011
Messages
1,685
Location
San Diego
We have a project that is old and has settled with high spots along the beams and dips in between. The floor slopes enough that file drawers may open on their own. pencils roll across tables, etc. The question came up regarding if there is a code section that would address this issue in terms of maximum allowable slope. Other than a 2% maximum cross slope for an accessible path I am not aware of another code section. Nothing in Chapter 12 regarding interior environment. This is California by the way.
 
Neat and workmen like manor? Performance specification in the project documents. Structural deficiencies? is it so unsafe the BO could cite a hazzard, or does the furniture require a liberal amount of shim stock under it?
 
I doubt that there is a code requirement that was in effect when building was originally permitted. Thus, the question is whether the owner of the building is motivated to correct the problem.

Shim the legs of the tables and desks.
 
We're in an old government build post office building and between the foundation walls if was backfilled with sand, well sand settles and so did the concrete floors. We have had recent movement where pictures on the walls have moved and floor cracks and floor displacement has occured. There are uneven openings below several door in the building. But the building is still serving a purpose and functions. Our front door nolonger meets ADA threshold requirements which would be a major reconstruction project. I to have the file drawer issue with drawers that stick, a good reason to go paperless!:eek:

An ADA issue at the door but no other code issues on an existing building.
 
These sound more like convenience issues than legitimate life-safety issues. I'm not sure I could apply current tolerances on floor slope to an existing building, unless it was a new floor going in.
 
There are no structural deficiencies. It is more of a personal comfort issue in terms of the sloping floors. The question is really being posed because if they attempt a remedy they would like a tolerance that is somehow rooted in code to shoot for. The concrete industry has requirements for slab flatness and levelness. For wood framed construction I have not seen anything.
 
"We have a project that is old and has settled with high spots along the beams and dips in between."

Sounds like undersized joists. It might be easier to add an intermediate beam than to sister all the joists, especially if wiring is running through the joists. Aim for the corrected floor being as close to level as practicable. It will still sag over time, but it won't be as bad.
 
Inspector Gift said:
Interesting question.

An acceptable answer might be, "Floors shall be level, but may have a maximum slope of 1 unit vertical per 48 units horizontal in any direction."
Click to expand...
So, what you're saying is; 5/8" of an inch per foot is bit much? That's what they built into just one part my new home, and all the floors are trip and fall hazards. The contractor told me I was asking for perfection, but he volunteered to install hand rails in the hall for me to hold on to so I don't fall. Yeah, right. 2-1/2 years later, and still not fixed.
 
Deflection is measured when a force is applied. Slope is a permanent condition. fatboy has intimate experience with both and can explain it better than I.

I must say, your building code has an index that is far superior to the US codes but your dimensions are wack.
 
Years ago a firm that I worked for designed a factory with floor that sloped in the direction of the assembly line conveyors. It required significantly less power to operate the conveyor motors.

Other than accessibility code, there is no life-safety code requirement that floors be level.

Many rehab project use self-leveling gypcrete to fix problems on old buildings: https://gyp-fill.com/gypsum-concrete-lightweight-concrete-floor-leveling/

Gypcrete is not good for areas that will receive water. If you need a concrete surface instead of gypcrete, consider Ardex or equivalent: https://www.ardexamericas.com/products/subfloor-preparation/self-leveling/

Remember to check with your structural engineer regarding the additional weight of these materials.
 
Is more a building owner maintenance issue, not a code issue at this point. Check your lease and see if it requires the owner to keep building in a safe operating manor. Still a civil matter tho.
 
ICE said:
Deflection is measured when a force is applied. Slope is a permanent condition. fatboy has intimate experience with both and can explain it better than I.

I must say, your building code has an index that is far superior to the US codes but your dimensions are wack.
Click to expand...

As one who has lived in both metric and imperial worlds, I gotta defend the SI system. Try calculating rise/run in imperial; then do it in metric. Sooooooo much easier in metric. It's only the Excited States that lives in a bygone measurement era.
 
ICE said:
Deflection is measured when a force is applied. Slope is a permanent condition. fatboy has intimate experience with both and can explain it better than I.

I must say, your building code has an index that is far superior to the US codes but your dimensions are wack.
Click to expand...
I am not an expert on terminology between slope and deflection. Baring an expert correcting me, I would say that deflection is what the structural members do and slope is what a surface does. Based on the original description, it sounds like the floors slope because of the deflection in the beams in this case.

That index is one of the best tools when you are writing certification exams.

As Canadians, we are bilingual in all things, even our measurements. Even my tape measure has metric and imperial on it. 100mm = 4". Easy.
 
tmurray said:
I am not an expert on terminology between slope and deflection. Baring an expert correcting me, I would say that deflection is what the structural members do and slope is what a surface does. Based on the original description, it sounds like the floors slope because of the deflection in the beams in this case.

That index is one of the best tools when you are writing certification exams.

As Canadians, we are bilingual in all things, even our measurements. Even my tape measure has metric and imperial on it. 100mm = 4". Easy.
Click to expand...
Yes.
for example, this ramp that is made of concrete cast onto the ground has zero deflection, but lots of slope.
1672857616329.png

Think of deflection as a kind of bending.
Slope is a term that describes any angle above or below horizontal. Slope may (or may not) result from bending, or for many other reasons or design purposes.


A simple beam that is installed level and has no downward force on it will have almost no slope.
A simple beam that is installed level and has some downward force on it will have slope, because the midpoint of the span is sagging lower than the end supports.

A simple beam that is pre-built with a camber (upward bend), can be loaded in such a way that the load flattens it to level.
 
Inspector Gadget said:
It's only the Excited States that lives in a bygone measurement era.
Click to expand...
Well, Liberia and Myanmar also use imperial. Credit the homebuilders for using their political clout to thwart the transition in to he 1960s. IIRC, it was at same time Canada transitioned and in the end it cost them like a tenth of what was expected.
 
Our codes are in metric but the construction industry is in imperial. This often makes me feel like AARRRG!
 
JPohling said:
There are no structural deficiencies. It is more of a personal comfort issue in terms of the sloping floors. The question is really being posed because if they attempt a remedy they would like a tolerance that is somehow rooted in code to shoot for. The concrete industry has requirements for slab flatness and levelness. For wood framed construction I have not seen anything.
Click to expand...
How big of an area are you trying to correct? Does the carpet (or other flooring) need to be replaced anyways? With flooring and base board removed (if the area is small enough) use a self-leveling gypcrete type of product. Once dry and new flooring installed it will be good as new.
 
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