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minimum floor height above grade


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I inspected a newer home built in the middle of of a former farm field. It is out in the middle of nowhere with no municipal inspections, constructed on a monolithic slab with brick veneer. No weep holes, no flashing. The exterior grade is virtually even with the top of the slab, and there is no slope away from the home. I'm aware of the 6 inches in 10 foot slope rule adjacent to the foundation, but I can't find any specific information indicating a minimum height differential between the grade immediately adjacent to the home and the floor line inside the home. 6 inches is the minimum number I've always used but I'm wondering if there is any actual code section which deals with it. If so, I haven't found it yet. Anyone know the answer of have an IRC code# for me? The builder is not cooperating with the owners and I need some back up info to help my clients.

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What's the clearance between grade and lowest course of brick?

A house like that, I'd be doing my absolute damnest to write up every single fundamental violation of accepted building practice I could find. You might as well just rename my report 'Why we have Building Codes'.

Marc

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Marc, that would be a negative number; the brick extends below grade. There's no exposed foundation anywhere. There were several other issues that I wrote up since I assumed that litigation was forthcoming, and it is. The plans were actually pretty well done but the builder seemingly didn't read them.

Compounding the problem is the fact that it is approximately 130 feet from the house to the drainage ditch out by the street and there's only 21 inches of fall at best between the floor height and the ditch. That's about one percent slope! Trying to simply regrade the yard won't work.

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I had a case that I was an EW on about 8-9 years back with the exact same problem. I'm not sure if I can put my fingers on the case but the height of the slab in relationship to the grade is covered under code but if I recall properly it is more along the lines of the slab must be higher than the exterior grade but it does not spell it outing inches.. I'll see what I can find.

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Ok, I found it?... With the case that I was on we had the Blueprints and the architect had detailed the slab as being 1.5" higher than the exterior porches, etc. This made it easier for us.

In the IRC it is not spelled out in inches how high the slab must be above the grade.

We also used from the IRC R401.3 Drainage? It basiclly states: Grade shall fall away from the foundation a min of 6" the first 10' .

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Thanks guys. I already knew about 401.3. The info was helpful, but in this case the best additional ammo/info I found was 403.1.7.3 which specified a minimum floor height above the drainage ditch. This allowed us to "back into" a minimum floor height requirement.

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