Pole barn on plate?

geog272 · Nov 30, 2013

I am working with a builder to design a 26X26 two story pole barn. I live in Northern New England. The gravel pad is done. I have only ever seen other people's pole barns done with the poles set into the ground, in a concrete footer, below the frost line, which I think means something like 4ft deep here.

This builder suggested that rather than setting posts in the ground, we do a "plate" consisting of pressure treated 2X8s that sit on the gravel pad, then the barn on top of that.

I am wondering if anyone has ever heard of or used this method, and if so will it hold up and be structurally sound?

Thanks in advance!

DT86 · Nov 30, 2013

I have never heard of this, but that doesn't mean much. How do you secure the plate to the ground? What about the posts to the plate?

Murfster3 · Nov 30, 2013

What is going to anchor the plates, it seems like to me with the frost you will have problems.

Carl_NH · Nov 30, 2013

No never heard of this method on gravel - as others state frost, anchoring etc will be issues. You need some footing/sonotube/post in the ground to attach the 2x8.

Also, 26x26 is not a 4' common dimension - like 24x28 or 24x32 so you have standard 4' O/C for materials.

Then 2 story, assume you will have 10 or 12/12 pitch, and have you decided on support for second floor, like posts or a steel beam, or using floor joists/trusses? There is a company in Biddeford that makes these floor trusses so you don't have posts or steel.

Woody65 · Nov 30, 2013

geog272 said:
I am working with a builder to design a 26X26 two story pole barn. I live in Northern New England. The gravel pad is done. I have only ever seen other people's pole barns done with the poles set into the ground, in a concrete footer, below the frost line, which I think means something like 4ft deep here.

This builder suggested that rather than setting posts in the ground, we do a "plate" consisting of pressure treated 2X8s that sit on the gravel pad, then the barn on top of that.

I am wondering if anyone has ever heard of or used this method, and if so will it hold up and be structurally sound?

Thanks in advance!

I am surprised a builder in the northeast would recommend this type of building. I have never seen it done or attempted it myself except for a small garden shed ( 8'x8'). There are two reasons to sink the posts. 1. To prevent settling/heaving in the winter/summer thaws and freeze. The other is to give the structure shear strength ( side to side stability). They can be bolted down to concrete pillars that are below the frost line. But not a 2x8 that is just sitting on top of gravel. A good noreaster and the poles would pull loose from the "plate" and topple the structure. Sill plates are used in stick framing and are bolted down to a concrete foundation every 4 feet or what the architect/engineer requires. Did he not explain his method fully?

bandaidmd · Nov 30, 2013

this is a great alternative to wooden posts in the ground.
https://www.permacolumn.com/

Mike476 · Nov 30, 2013

Just built a 26X42 barn. Compacted dirt, laid concrete block, starter course of shingles on top of that and then 6X6 pressure treated as my sill, framed up from that. Just had over 100km/hr winds and driving rain last week, no anchors and building stood it no issues at all. A lot of wieght in a stick framed building.

As has been said in other threads, most older barns were built in a similar fashion, sometimes on rock walls.

Woody65 · Nov 30, 2013

Mike476 said:
Just built a 26X42 barn. Compacted dirt, laid concrete block, starter course of shingles on top of that and then 6X6 pressure treated as my sill, framed up from that. Just had over 100km/hr winds and driving rain last week, no anchors and building stood it no issues at all. A lot of wieght in a stick framed building.

As has been said in other threads, most older barns were built in a similar fashion, sometimes on rock walls.

<img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=348174"/> <img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=348175"/>

The OP stated it is going to be a pole barn. Not a stick built structure. Like comparing apples and oranges.

dave1949 · Nov 30, 2013

Yes, it used to be the way barns and sheds were built. Those buildings didn't blow away. My son has a friend whose family owns a log cabin camp in Maine that sits on rock piers. It's ancient. They do have to shim a pier here and there every couple years to keep it level. Obviously, you won't get the exact stability of a below the frost foundation.

I know of a goat barn over in St. Albans, ME that was built much the same as Mike476's barn. It hasn't moved. It makes a big difference on what the building is used for and how exposed it is. With animals and hay/straw bedding/manure build up, I doubt the ground freezes below the sills. People used to bank snow against their foundations and walls too for frost protection and to cut the wind whistling through the cracks.

Most small utility sheds bought ready assembled and delivered by sliding off a truck sit on 4x4's. They don't blow away and stay reasonably level if placed on a compacted gravel base with drainage, with no heat.

I don't know what the best advice is. For that size building I would choose standard stick framing, not poles.