Max flooring deviation at transitions

Can someone provide the maximum flooring deviation (height difference)between floor coverings (e.g carpet to wood, tile to wood) that would be considered a trip hazard. I can not find an IRC reference for this.


I would apply the 3/8 inch rule that IRC does for the variance in riser height as a definition of a trip hazard until something more definitive is in place. (R311.5.3.1)

I go by the depth of the threshold and the taper.

Many times I see thresholds higher than 3/8" when transitioning from hardwood flooring to tiled areas over a mud substrate. Tapered oak thresholds can be pretty high.

Are we talking about the height of the threshhold or the variance between floors in the absence of a threshhold?

I was asked a few days ago to manufacture some threshold pieces, going from hardwood to carpet and linoleum. Height needed is 1 inch. I’d call it a trip hazard, but that’s what the guy wants.

I understood the question to be the tolerance between the transitions.

I have some details here to share and if it does not help just make me understand what it is needed.

I believe this would show examples of transitions.
And yes, I don’t think any transitions should exceed 1/2" Residential or Commercial.

Anything higher is usually at exterior doors of a Residential Unit.

Multi-Units with common entries would be 1/2" max.

Hope this helps.

Marcel :slight_smile: :smiley:

Yes, I am questioning the variance between floors in the absence of a threshhold? Seems to me that 1/2" might be a bit extreme. I would be more inclined to think 3/8" would be more realistic and much less of a trip hazard.

Thanks for the comments.

Rod, the maximum rise should not exeed 1/2" on anything and less if the flooring material is properly installed with transition strips made for whatever product of flooring is being used.

Check out this link and browse around, click on the pictures for blow ups and products for different uses used in flooring of any type.

A flooring material is just not dead ended , because wether 3/8" or 1/2" you will trip.

Hope this helps more.

Marcel :slight_smile: :smiley:

I agree at either 3/8 or 1/2" your foot will scuff the edge and could create a hazard, but I was hoping to find an exact tolerance. The info provided seems to be a good option when the surfaces are not flush.

Again, thanks for the comments.

Can anyone tell me: I have a 2 and 3/16 inch higher floor height in my kitchen then the living room and entry way room. Is that to code or what do I have to do to fix it? It is probably due to adding plumbing under the floor to a 1917 home that did not have indoor plumbing. I am asking because a realtor said it would not pass inspection.

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Nothing in a 1917 home is “code”. As far as pass inspection, it means it will probably be noted as a trip hazard. Don’t listen to realtors when it comes to code. They tend to throw that term around a lot.

1 in 8 is the code maximum slope for a ramp. R311.8.1. I would not exceed this slope at a transition.