"Lean to" addition

[FarmerSid]

Hey all! I need to add a lean to onto my barn. Too much stuff inside that needs to get out but still needs to be under cover. It's going to be 18' wide and 40' long. I need to dig some post holes but am wondering what is the better way to go. I have about 3' of depth then I'm on flat limestone. Should I bury the pressure treated posts or fill sono tube with cement and attach the posts on top with saddles?

Cheers!

Sid

 

[ozyborn]

Pouring footings and keeping the any wood, treated or not, off the ground is a good thing.

 

[walrus]

Should I bury the pressure treated posts or fill sono tube with cement and attach the posts on top with saddles?

Cheers!

Sid

Frost will lift concrete, concrete conducts cold quite well and it will freeze surrounding soil easily. A lot depends on soil conditions as to whether or not it will bother.

 

[holdover]

did my lean-to which is 16 X 36 this way; dug down 40" to get well below frost line, poured 18X18" footer 6" thick, used 6 X 6" ground treated 12' posts on 8' centers 2 X 10 treated header, 2 X 10 rafters with painted steel roof to match rest of garage, had some 15" windows that I put up next to top of wall and sheathed with T111. Plan on comong back an pouring a 4" slab when I get some extra $$$$. wish I had poured the lean-to slab when I built the garage!

 

[FarmerSid]

I wish I put the lean to on when I built too! I knew at that time I would need it but I just finished picking all the money of the tree. I can't get below the frost line as I only have 3' of soil, if that, till I hit flat rock. Would it be smart to surround the post with clean gravel to help drainage and prevent rot?

 

[Daniel Dudley]

I have seen sono tube pours shift in the soil. I would want to make it a continuous pour with the footing, which should be pretty wide. I would also want to pack around it with Item 4 gravel.

With a PT post set on ledge, you would not need to worry about shifting or pouring a footing.

 

[Zeke]

Can you drill some rebar in the limestone?