I’m having a pre-built 16′ x 36′ cabin placed on piers (30 per manufacturer’s spec). I’m planning on using (3) 8″ x 8″ x 8″ corner block as piers. My question: do i need to mortar them together, or can i dry stack them? Any help would be welcome. (see attached pic of what I’m thinking)
To prevent moisture buildup and improve performance, install a continuous air barrier—such as drywall or specialized membranes—under tongue-and-groove boards or other interior wall paneling.
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Replies
Pic pretty small. But, what are 2 x 8 treated doing top/bottom? Was the size structure and placement spec’d?
I had planned on using the treated to fasten my underpinning to (not a good idea?). Yes, the manufacturer spec'd the placement and size but not the design.
Best check with inspection as wood “shims” under beams is not permitted. Treated blocks between piers and footings, not a good idea. Mortar up the piers and fine tune with steel or spec’d composite shims as used by iron workers.
But location may vary.
Where is this going? does it freeze there? what kind of site prep under the supports are you planning?
Are you going to tie the structure down so it does not blow away in high winds?
Northern MI. Yessir it's cold up here. For site prep, (per the building inspector) i'm putting a 42" x 10" concrete piling under where each pier sits and then pour an 18' x 38' x 5" of concrete pad over the top (then place the piers on the pad). Per anchoring, i'm planning on using (4) hurricane straps on each side (per the inspector).
Your soils must drain pretty well for the inspector to ok the slab. (pilings sound like they will be below the frost line, but if there was going to be much water in the soils, it seems like the harsh winters would heave the slab )
How are you planning to anchor the hurricane straps? If they will anchor to your support columns, this impacts the discussion on how to fasten them together.
I would not want treated wood resting on the slab, between it and the columns. I would want masonry to the top of the columns. Seems like good choices would be to mortar them in, or dry stack and coat the sides with surface bonding cement (which still needs the first course mortared in place) You can also fill the cores.
Understand the top treated part. What does the pre-fab cabin expect?
And It seems like a good idea to run whatever you plan past the inspector.