Crawlspace Foundation brick veneer to concrete porch transition
I’ve spent months scouring the internet and can’t seem to find anything at all showing me a reasonable way to do this.
For reference, this is zone 4a, Kentucky. Conditioned crawlspace or possibly basement.
What is the best, most reasonable way to make a transition between a brick veneered house and a concrete porch? It seems any example I see shows houses with regular siding and doesn’t address the situation if the house has brick veneer.
This will be new construction so trying to get it right the first go around. I feel like most builders around here would typically set the floor joists atop the foundation wall with a brick ledge to support the brick. In that case the concrete porch would be against the brick, then air gap, then framing. Where would the brick drain to from there? Would another layer of metal flashing above the porch solve the problem? Would I need a piece of flashing between the brick and concrete? Dimple mat? No matter how much flashing detail is done, I still feel this isn’t the best way, but would be the way a builder around here would do it.
Another option would be to drop the floor joists into the foundation wall, but this brings the concern of not allowing room for rigid insulation between the concrete and joist end.
Can the brick be set above the porch slab after it is poured? I would then worry about freeze/thaw cycles and the integrity of the brick.
Maybe I’m overthinking this. My parents house was built about 13 years ago, and they just poured the concrete against the brick, minimal step out the door, with wood floor joists set atop foundation. I am not sure of any flashing detail behind the brick. This seems the typical way to do it, but I feel in time, this can become problematic. There is no issue with their house that I know of, but I don’t feel this is the best way.
Plan to use dimensional lumber as floor joists, I just don’t like the idea of TJI in a potentially wet crawlspace. Floor trusses would be an option, especially as a top chord bearing situation like the example below. However, that comes at a cost. If I can make a good transition with dimensional lumber, I’d prefer to do that.
The top chord bearing floor trusses would allow to insulate the foundation wall much easier. If using dimensional lumber joists in a dropped scenario, insulating could be challenging.
I have attached some examples of how it could be done to minimize issues, but will be trading one issue for another. Please share your thoughts on the best approach.
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Personally, I would not want any exterior impervious surface that is directly adjacent to the building to be above any portion of the building that is not designed to be below grade (ie: the wood framed floor).
Is your goal to have the finished floor of the porch be at the same elevation as your first floor finished floor elevation? It seems like there should be an existing detail out there somewhere. I guess you could either have your floor sit on top of your foundation wall or be attached to it so that the top is at the same level as the top of your foundation wall. This would depend on whether you want one step or two up into your house.
I've attached a sketch of how I would imagine doing it but I'm sure there are as many ways to design it as there are designers, some better than others.
Good luck.
Your best bet is to drop the floor joists/increase foundation height. Put a through wall flashing/weepholes/etc from your wrb through the brick above the exterior concrete elevation.
I'm not sure what all the options are for securing the floor joists to foundation are. Around here crawlspaces are rare, and the joists are usually set on an interior framed basement wall.
Or switch to a narrower foundation on the inside (depends on interior foam thickness and required bearing) and set the joists on another mudsill.
You could also use exterior insulation for the foundation and a lintel for the brick.
I would not set the exterior concrete on a foundation ledge.
Kybuildright,
If the porch is going to be close to the same height as the floors inside, unless the exterior grade is going to drop immediately wherever the porch ends, you have the same problem everywhere around the house - not just at the porch.
(Edited several times because I misread your post)
If you don't mind a few steps from the porch to the surrounding grade then I would raise the height of the stem-walls there to 2" above the porch slab. On the interior form a ledge at the same height as the top of the rest of the stem-walls, wide enough to hold 1 1/2" of foam board, and provide bearing for the floor joists. Use blocking between the joists rather than a rim-joist to save space.
If you don't want the porch floor elevated, consider using this detail everywhere.