Porch slab and wall interface detail
The front porch of my house has failed due to what I can only assume to be an improper foundation, I am looking to replace it and the foundation with a proper depth and thickness poured continuous footing with CMU block wall at both the perimeter and the two porch columns. The wall CMU will be poured full and tied into the slab rebar. My only question is the interface at the building connection, currently the brick there is showing signs of degradation, not to mention it doesn’t fit at all with the overall style of the house. The top of the rim joist is about the same elevation as the top of the current slab. the house is located in climate zone 6 (Michigan)
How do I connect the slab to the house frame without causing a water issue at the connection?
Do I bite the bullet and strip the brick off of the front of the house? then what would that connection look like?
Potentially I would follow this up with a natural stone at partial height vs. the full height brick currently in place.
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Replies
Hi Kenneth -
You need to completely decouple the exterior porch slab from your structure both in terms of heat and moisture management.
你的轮辋托梁是否靠在内部隔离的门廊板上？作为解耦的一部分，您可以在外部上使用刚性绝缘，刚性绝缘用作毛细管和热断裂。当您重做时，您需要一个终点细节，但由于屋顶的门廊平板和结构之间的新热量和防潮，因此可以使用任何数量的材料进行饰面盖，这些材料简单地保护下面的绝缘材料。
Peter
Peter,
Thank you for the input, Unfortunately I don't know exactly what the current connection is... it appears that maybe they installed the brick exterior first and the poured up to it, so the brick air gap /back plane would act as a capillary break.
So if i tore off the brick and put a rigid foam panel (POLYISO probably) on the sheathing/ framing would I need to install a foundation around the entire porch perimeter?
Hi Kenneth -
I think the best approach is to take off the brick veneer. That way you can get a decent level of insulation in the wall and an air barrier as well.
Do you need to re-found the porch slab? If the existing slab is moving enough to create cracks, and since your porch roof is tied into your home, you probably need to re-found the porch slab. I don't know your climate and that likely has impact on just how much your slab moves over the course of a year (frost-heaving in a cold climate being the main source of movement).
Peter