Backfilling pole barn, need advice

[DrewStyduhar]

Whatcha think about using roofing tar instead of paint? I use tar for fence posts I set (dont paint bottom) and seems to hold up well.

The finished EXTERIOR grade is the bottom of this main skirt so figure there will be a foot or so of dirt/fill on the outside in direct contact with this second skirt.

Drew

 

[Midniteoyl]

Whatcha think about using roofing tar instead of paint? I use tar for fence posts I set (dont paint bottom) and seems to hold up well.

The finished EXTERIOR grade is the bottom of this main skirt so figure there will be a foot or so of dirt/fill on the outside in direct contact with this second skirt.

Drew

Think tar would work.

As for the outside fill, using gravel up against the board would be better. 8" to 12" out and 12" to 18" deep would also keep the groundhogs and whatnot from digging underneath your slab.

 

[DrewStyduhar]

Looks like mernards carries it. You guys ever used something like this?

https://www.menards.com/main/building-materials/landscaping-materials/landscape-edgers/8-black-plastic-lumber/1129976/p-4221069730084379.htm

 

[Midniteoyl]

Looks like mernards carries it. You guys ever used something like this?

https://www.menards.com/main/building-materials/landscaping-materials/landscape-edgers/8-black-plastic-lumber/1129976/p-4221069730084379.htm

View attachment 708503

Black or not, I'd get documentation of the UV resistance.

 

[DrewStyduhar]

Ill call them tomorrow. I mean, they sell them for use outside as landscape edgers. Mine would be buried. Ill get more info.

Drew

 

[nyone]

Why dont you backfill the exterior with dirt then the inside with gravel? I dont see the need for the extra board to begin with.

 

[mikester]

I'd put a 4 foot wide concrete skirt all around with a strong slope away from the barn. I don't want water or critters.

 

[deezler]

Even untreated wood would still last for years in the ground. With current basic ground-contact PT, I can't see how it would even rot within a decade. After which, yes the board loses structural integrity, but it doesn't just disappear and leave a void. Even if it did, after 10+ years, the gravel under the slab is going to be well compacted and fixed in place. It's not risky; just maybe not worth the $$.

It's really just up to you if you think the extra PT boards will assist your backfilling. To keep critters out from under your slab, concrete is definitely better long term. A 2-3' deep concrete rat wall is best.

But like midnightoyl said, you can just paint the PT boards first, and they'll be essentially waterproof.

 

[Xfaxman]

Looks like mernards carries it. You guys ever used something like this?

https://www.menards.com/main/building-materials/landscaping-materials/landscape-edgers/8-black-plastic-lumber/1129976/p-4221069730084379.htm

I used plastic deck boards on this old cattle guard, where the tin dirt blockers had rusted away. They worked well:

 

[Macinnis]

I just went through this with my building when I had the concrete put in.

what my concrete guys did was to put some gravel on the outside of the barn as to not let any concrete ooze out during the pour. They then leveled out all of the gravel inside of the barn up to the base of my concrete rat board.

so the 4” of concrete poured inside complete met/covered my concrete rat board.

once the concrete was done, the final grading was immediately done outside of the barn so that the gravel wouldn’t have anywhere to go during freeze thaw. I hope this is going to work.