I'm planning to build a new detached garage and will be handling most of the work myself, except for the concrete pouring part. My home inspector mentioned that garages should have a curb that's about 6 inches above the soil level to protect the wood from moisture damage. However, I've noticed that very few garages actually seem to have this curb. Is there a reason for this? What's the deal with garage foundations – is a curb standard practice or just a recommendation?
3 Answers
There are actually two main types of garage foundations. One is a grade beam foundation, which features a perimeter footing topped with a concrete grade beam, allowing for the curb around the garage. The other is a slab on grade, where the slab is poured with a thickened edge that's flush with the surface. The slab on grade is typically more economical and is the go-to method for detached garages in my area.
The differences could be due to when the garages were built. Building codes can change, and not all areas adopt them at the same pace. For example, at my son’s old house, the bottom plate was right against the slab, and believe me, that led to some serious decay issues.
It seems like the issue might stem from what you're looking at – are you checking the interiors or just the exteriors? There typically should be a curb, but it can get obscured by how low the siding is brought down, too much fill dirt, or neglect in landscaping. Your inspector is spot on, and you're right about wanting to keep that wood off the ground to avoid rot. A lot of folks just don’t like the way curbs look, so they overlook the potential problems it can cause.
Exactly, and that’s also common with pole structures. But I haven’t heard of calling a foundation a curb; maybe it’s just a term used regionally?