|
| Author |
Message |
CamaroMan
Member
|
# Posted: 26 Sep 2025 09:45pm - Edited by: CamaroMan
Reply
Hi - busy throwing ideas around here but considering 12" square blocks and filling with 1/2" rebar instead of messing with forms etc- trying to keep costs down.
Ill prob space them 6ft so will have a pretty strong base- top of a mountain ground is pretty solid with rock pretty shallow. Will prob go down 2ft and bring it up about a foot off the ground. Will be using cement board on the sides to keep floor warmer and moisture out-
planning 16x20 or there about- prob go 2x8 floor joists-
|
|
Brettny
Member
|
# Posted: 27 Sep 2025 08:32am
Reply
Skirting dosnt keep moisture out. In fact it can keep moisture in and will nee to be vented. Why not just insulate the floor joists and not skirt at all. Nothing to vent and your floor will be warmer because theres very little warmth in the ground in winter. In fact your more likely to have thawed ground under a skirted cabin in winter due to heat loss not ground heat.
|
|
DRP
Member
|
# Posted: 27 Sep 2025 12:54pm - Edited by: DRP
Reply
Joist spans are here;
https://codes.iccsafe.org/content/VARC2021P1/chapter-5-floors
Use the 40 psf table, cliff notes.. 2x8 in common framing lumber is good to 12' span, 2x10 to 14', 2x12 to 16' span at 16" centers using #2 lumber of most available species.
The pic is from chapter 4 of the above link. a treated wood foundation on a gravel trench. No concrete, braced and with continuous floor support, recognized design.
|
|
Grizzlyman
Member
|
# Posted: 27 Sep 2025 07:22pm
Reply
Look for bigger blocks. I used 18” square blocks and filled with concrete.
|
|
CamaroMan
Member
|
# Posted: 27 Sep 2025 09:30pm
Reply
thanks drp will take a look
|
|
MrDoug
Member
|
# Posted: 22 Oct 2025 02:39pm
Reply
I am in the "thinking about it" stage myself. Looking at 12x16 with a 4 foot porch, so 16 square footprint. There will be no plumbing, electric or interior walls, just one big room. Furnishings will include a full size air mattress, a card table and plastic chairs, MAYBE a bookshelf, and a tent wood stove ( about 20 lbs). Thinking about 2x6 floor joists, spaced at 4 foot with a 4x4 post setting 8" below frost line in concrete at every intersection. ( think big chess board with 4 foot squares). Floor would be 1/2" plywood. Steer me in the right direction. Am I expecting too much support from too little, about right, or serious overkill?
|
|
gcrank1
Member
|
# Posted: 22 Oct 2025 02:56pm
Reply
You NEED more floor joists
It would be best to start your own thread so it all doesnt get mixed or lost in this one 
|
|
rpe
Member
|
# Posted: 22 Oct 2025 03:29pm
Reply
Back to CamaroMan's question...
In our area the local Rona building center carries 'bull nose pier blocks' that are 12x12. I used them when building piers for an addition this spring. I dig down, pour an 18x18 pad on the bedrock, drill rebar into bedrock, and thread blocks over the rebar as I build the stack. The stack is filled with concrete as I go, and final block trimmed or padded at desired elevation. 6x6 saddles are set into the top, and hold the beam in place.
|
|
|
gcrank1
Member
|
# Posted: 22 Oct 2025 04:46pm
Reply
Looks substantial, I like it
|
|
|
