Pier foundation.

[ADAguy]

He is only proposing to address the perimeter, what of the interior supports? No interior walls? Under slab membrane?
Watching too much DIY.

 

[TonyTheTiger]

A recipe for disaster. A 4" slab on grade resting on piers?? No building official should issue a permit for this idea.

Don't believe that you can protect him from what he "knows" will work.

I don't "know". That's why I ask.

The slab is not going to be bearing any weight of the house, nor will it be supported by the piers. It's to fill in the area under the house to create a clean crawlspace. That's all. It will be properly vented for radon abatement (a big deal in this area).

One of my goals is ease of access for maintenance. I even designed the closet placement and wall panel removability for access to the shower plumbing without having to tear out a wall, as well as convenient plumbing and wiring runs.

I believe I have a good idea for a small home for a single person, a retired couple, or a "mother-in-law" suite etc. It will be efficiently insulated, nicely, comfortably, and conveniently accessorized, and legally movable if necessary, but not a "mobile home" or "tiny house". I will be combining new technology with old. A semi-open floor plan using old ways of engineering for airflow purposes. No back door, but an egress window in the sleeping area. Storage areas fit in between traditional appliances and bathroom fixtures. Large bathroom with laundry.

Meeting every applicable code and exceeding most for sturdiness and longevity is my intent.

 

[TonyTheTiger]

2x8 will span 15' on 16 inch centers. My Max joist span will be 14'6". Plus in heavy areas I plan on 12" centers. Ten piers, not 6. Max span on perimeter will be 7'6" on the ends and 8' on the sides. Well within code for a single 2x10, let alone doubled..

 

[TonyTheTiger]

The only interior wall will be to the bathroom in back. 7' deep. That area will have 12" on center joists.

The sleeping area will be a partial wall.

 

[TonyTheTiger]

I was guessing 24" of cellulose. Don't think that's quite R70

 

[TonyTheTiger]

I saw this on a build off the grid Alaska show


https://www.technometalpost.com/en-US/advantages/helical-piers/

Interesting, but without digging a hole, how do you know the load bearing capacity of the soil?

 

[TonyTheTiger]

I was guessing 24" of cellulose. Don't think that's quite R70

Oh, I guess it is. I read something wrong.

 

[TonyTheTiger]

I saw this on a build off the grid Alaska show


https://www.technometalpost.com/en-US/advantages/helical-piers/

And I found this for exterior walls.

Structural Insulated Panels | SIP Panels | Insulation Panels | EZ SIPS https://structuralinsulatedpanels.com/

 

[TonyTheTiger]

He is only proposing to address the perimeter, what of the interior supports? No interior walls? Under slab membrane?
Watching too much DIY.

Inside length of joists will be 14'6". No need for interior bracing.

And 16' is the maximum withh. Insulation, siding and all, to meet transport requirements. 40 is the length including front deck. Living area will be 34 or so, whatever the stud spacing works out to.