How to get slab details right for clay soil build
I live west of Nashville (Zone 4a) and will be breaking ground very soon on a 1300 sq ft ranch for my family.
I want to use a slab,and wanted to know what are some safe slab details but I have “heard” that the soil conditions are not slab friendly in this area: clay soil mix with small rocks. It is called chirt locally.
I thought a stiffened slab might be a good fit or perhaps an overdig slab and fill it up with creek gravel and rocks?
Hiring a guy to run a rod into the ground to determine compaction is not to spendy, but getting an engineer to design a slab is not something I want to add to my world record attempt at low budget, poor man’s building science techniques as my pockets are shallow and I am not going to take on any debt.
Local inspector does not require engineer for slab. He just built his own house on a slab. About same size house, but he followed typical slab on grade with just the edges and centerline dug to frost line for load bearing purposes and 4″ everywhere else. However, I do not want a nightmare later. Spending a more on the slab that is overkill is better to my mind than paying a few thousand for an expert. The only cost in my mind is the materials as a week extra of my time is ok with me and I charge myself zero $$ 🙂
I plan to have a few loads of chirt braought in also in order to elevate the site for excellent drainage as well, if I do the stiffened slab (waffle)
I thought a slab would serve well for a few reasons: Easily eliminate nasty crawlspace without need to make crawlspace part of conditioned space. Finish floor does not need any covering as I plan to stain concrete and it will save money.
I am doing 98% or more of all work myself on this house and have even scrounged a lot of materials already (roofing, siding, windows, cabinets, polyiso, light fixtures, etc..etc…). I have built 70% of my last two homes, but was completely ignorant of building science for those houses. I will follow a VERY budget minded approach to this build while working for a tight, well insulated, and properly ventilated build.
Here is the floor plan and roof will be built with rafters, no trusses.
I very much appreciate your advice or clarifying questions for a budget approach to getting the details right.
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