number of block courses above grade

[crosscutter55]

How many courses of block would you use for a stem wall   ? 48" to the bottom of the footing would work for a good frost wall height , but how many courses above grade would you add ? Anyone know where i find some good detail of a crawlspace to a full foundation so i can better understand these connections ??

 

[Chopsaw]

I am not so sure you will find any standards on this sort of thing other than local regulations for frost wall depth and height above grade for surface water infiltration.  There are many many other factors you will need to consider, such as soil conditions, water table, drainage, site grading, window placement, access, and the clients intended use of the space.

It will also depend on where you are building, such as a flood plane, side of a mountain, or a swamp. If you study some of the existing buildings in the area and understand why they were built the way they were, that would be a good start.

[Chrisb222]

23 hours ago, crosscutter55 said:

How many courses of block would you use for a stem wall   ? 48" to the bottom of the footing would work for a good frost wall height , but how many courses above grade would you add ? Anyone know where i find some good detail of a crawlspace to a full foundation so i can better understand these connections ??

 

Here we use four 8" courses above footer. I leave one full 8" course above FINISHED grade (after grading up to create drainage slope). This gives 32" below grade frost protection, code for this area.

 

ICC Code is 6" minimum between ground and non-decay-resistant finish materials:

 

Quote

SECTION R319
PROTECTION AGAINST DECAY
R319.1 Location required. Protection from decay shall be provided in the following locations by the use of naturally durable wood or wood that is preservative treated in accordance with AWPA U1 for the species, product, preservative
and end use. Preservatives shall be listed in Section 4 of AWPA U1.
1. Wood joists or the bottom of a wood structural floor when closer than 18 inches (457 mm) or wood girders when closer than 12 inches (305 mm) to the exposed ground in crawl spaces or unexcavated area located within the periphery of the building foundation.
2. All wood framing members that rest on concrete or masonry exterior foundation walls and are less than 8 inches (203 mm) from the exposed ground.
3. Sills and sleepers on a concrete or masonry slab that is in direct contact with the ground unless separated from such slab by an impervious moisture barrier.
4. The ends of wood girders entering exteriormasonry or concrete walls having clearances of less than 0.5 inch (12.7 mm) on tops, sides and ends.
5. Wood siding, sheathing and wall framing on the exterior of a building having a clearance of less than 6 inches (152mm) from the ground.
6. Wood structural members supporting moisture-permeable floors or roofs that are exposed to the weather, such as concrete or masonry slabs, unless separated from such floors or roofs by an impervious moisture barrier.
7. Wood furring strips or other wood framing members attached directly to the interior of exterior masonry walls or concrete walls below grade except where an approved vapor retarder is applied between the wall and the furring strips or framing members.