Pole Barn on rock

[Aftershock]

Hi Everyone!

New to the forum.

We are looking at building a 36 by 50 pole barn on our 150 acres on the Canadian shield if possible. The granite however is not conducive to posthole augers. We have a Lucas swing mill with lots of pine and oak on the property so we hope to use most of the materials from our land.

My idea was to put in perimeter footings with anchors for the poles. my wife and I followed steeldust's thread and fell in love with the monitor style. Reading some of the other threads there were questions raised about wind, snow loading etc. I plan on building strong enough to handle all of the above. However with no post below ground will side loading from wind shear not be an issue. I could easily on the 2 outside row of posts anchor them diagonally down to the bedrock, but with the two rows of middle posts it wouldn't be an option because it would limit the maneuverability within the barn.

I prefer not to do stick framing as it's a lot more milling.

Would love to hear any comments or suggestions. Thanks!!

 

[Duffster]

Hi Everyone!

New to the forum.

We are looking at building a 36 by 50 pole barn on our 150 acres on the Canadian shield if possible. The granite however is not conducive to posthole augers. We have a Lucas swing mill with lots of pine and oak on the property so we hope to use most of the materials from our land.

My idea was to put in perimeter footings with anchors for the poles. my wife and I followed steeldust's thread and fell in love with the monitor style. Reading some of the other threads there were questions raised about wind, snow loading etc. I plan on building strong enough to handle all of the above. However with no post below ground will side loading from wind shear not be an issue. I could easily on the 2 outside row of posts anchor them diagonally down to the bedrock, but with the two rows of middle posts it wouldn't be an option because it would limit the maneuverability within the barn.

I prefer not to do stick framing as it's a lot more milling.

Would love to hear any comments or suggestions. Thanks!!

I think Pouring a sufficient footing will work fine. Really no different than using a slab on grade.

 

[magicheater]

Very interesting situation. Why not drill holes and make a re-bar framework for a level footing/floor and go up from there. U shaped holders for your poles anchored in the bed rock. Kind of rough to cover the insulated floor routine though. With the granite you do have the ultimate foundation. This is just an idea and I do not know how accessible concrete delivery is where you are. I am sure others will chime in if I am off base.

 

[Aftershock]

Hi Magic

I was thinking I could take box steel with an ID of 8" weld rebar to the bottom of it then fit the posts in this and then thru bolt.

 

[magicheater]

You would then be relying on the weld and not the mass gained by the concrete. Perhaps your ultimate usage would really help with deciding the strategy. Ever planning on insulating this box? Duffster thinks similar to me on this issue.

 

[Aftershock]

Yes, eventually planning on insulating and pouring a floor. How do you recommend anchoring the posts?

 

[magicheater]

The box steel affixed to the re-bar structure with the added mass of the concrete enveloping it would be ok for me. You could just extend threaded rod up and bolt down the box steel. You would want to make it a footing arrangement to allow for the insulation beneath the floor so your finished floor is in sync with your footing height. Think it through and seek other advice before you make your decisions.