Pier and Beam for 20x32 shop

Started by Landon, December 22, 2023, 03:59:00 PM

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Looking for some guidance on what size and how many beams I would need to build a 20x32 shop. Due to an elevation drop of a couple of feet, a concrete slab is not an option. With that question I was planning on building beams out of 2x6 material (basically using 3 2x6's of various lengths per beam and offsetting the joints), I was wondering can I use 4x6 by 16' and make sure there is a pier at the joint of the 16' 4x6? I've seen where most people tend to use piers on 8' spacing. Anyone have any thoughts?  


A shop for what kind of use? Concentrated loads on the floor from any tools or machinery?

Quote... using 3 2x6's of various lengths per beam...
A triple 2x6 built-up beam will not safely span 8 feet for anything other than a small garden shed.

The best floor for something like this would be to grade the slope to enable the use of a concrete slab.

If a pier and beam is done ALL the splices of the 2x materials must be located directly over the piers.

Question... is there a need for a building permit and inspections for the proposed project?
Just because something has been done and has not failed, doesn't mean it is good design.


This just a workshop not really any heavy loads, no vehicles, mowers etc. Some table saws, planner, etc.. I would love to do concrete but i have a 2' drop going out the 32 feet plus the 20 feet wide.


Honestly I'd build a stepped concrete foundation.

For my cabin I have about an 18" drop to close to 24" from one end to the other and I opted to use a post and pier foundation with 4x8 beams on 4" posts sitting on pier blocks and pavers per CP plans.  However, I've been slowly changing that by pouring an 8x16 foundation subgrade and building a cinder block wall up from there (surface bonded) and then pony walls up to the cabin.

I plan to try to finish that this spring as it's been too long but all in all the post and pier worked, just not that well ;)


My workshop had ~2.5ft feet of slope. Dug it out with the tractor, backfilled with well draining stone, and poured a slab. 20x30 slab area and 10x30 lean tos on both sides. I'd recommend against piers, but if you do it use built up 2x12s that well are blocked to keep from rotating. Use codebook tables for sizing. Your low end will likely be 3-4 feet above grade and the piers are going to tip over time.