Ideas for setting shed poles??

[1988mustang]

The snow will be here in Ontario in only a matter of days, and the pressure is on to get my sawmill shed completed.  I have decided to use old hydro poles to support the structure.  I had every intention of putting the poles 4 feet into the ground; however, mother nature has other plans for me.  I could only get 2 out of the 8 poles my desired depth.

Basically I have 2 corner posts in the ground at the back and need to get the others in VERY soon.  My problem is that for the other 6 poles I can only get down 1.5 feet at the most before I am hitting bedrock.  I'm not sure what  I should do to make sure the rest of the poles don't kick out and stay in place.

I was thinking of drilling a piece of rebar about 6 inches into the bedrock then drilling another 6 inches or so into the pole.   Set the pole on the rebar and brace the pole until the beam is in place and the rest of the building is in place.

Does any of this make sense?  I'm open to any ideas or criticism to better my ideas...  Any input would be appreciated...

[Bibbyman]

 



The posts on this addition to our sawshed are about 2' in the ground. I drilled holes in the section of posts below ground and drove in spike nails that were about 9" long.  I left them stick out about 5".  The post holes were about 18" in diamater.  I filled around the post with kwickcrete.

[1988mustang]

Thats not a bad idea at all.  Another problem I forgot to mention is that some of these poles will be sitting right on bedrock.  I basically scrapped down that section of the hayfield in front of my poured slab and discovered bedrock literally 3 or 4 inches down below topsoil.

[sgschwend]

You are  concerned about frost heave with the shallow holes.  Can there be heave from bedrock?  I don't know but wouldn't thinks so.

[PineNut]

I usually nail a collar of 2 x 4 around the base of each pole. After backfill, this helps hold them in the ground.

[1988mustang]

sgschwend:

I do not think that I'd be worried about the frost heave with them sitting on bedrock.  I probably should have stated earlier that my main concern was the poles kicking out from underneath the building.  To be honest my biggest fear is that my father will hit one of the front poles with the bucket of the tractor and the building will collapse.  It is kinda of a funny concern  but it does have real cause for concern.  He is only 61 years old but seems to be getting the early onset of Alzheimers...  He loves to help out but.... I could actually seem him dinging a pole with the bucket .... I'm definitely going to have a log deck to prevent the possiblity of him getting too close to building with the tractor. 

But hell he is my father and I want to enjoy whatever time I have left with him.  Plus its always a bonus having help at the sawmill   I just want to make this building secure as can be.

[Carpenter]

Attatching another piece of pole to the bottom of the pole to make an upside down T ( called a deadman) will increase the surface area of the pole and make it less likely to kick out.  It also makes it harder to pull out.  We put them at the bottom of corner fence posts all the time in the sand.  Since you are on the bedrock you shouldn't have to worry about the post sinking.  
    Another more costly solution would be to pour a concrete pad and anchor the posts to the pad.  You could pour your footings right on the bedrock.  
     I think if it was me for a pole building, I would just use the deadman and consider hauling in more dirt if needed around the poles.
      Your rebar idea would also work, to prevent kick out but, unless it is mortared or epoxied to the bedrock and attatched to the pole in some way it wouldn't do much  to prevent lift.  Do  you get much wind in Ontario?  Of course if the bedrock is solid enough and you could anchor the post to it say with a lead sinker and lag, (or some other concrete fastening system) with an L shaped piece of steel from the bedrock to the post, you'd never have to worry about it going anywhere.  Just cover it up with dirt for looks.
       Good luck with whatever you do.  

[Hanson]

Your rebar idea will work just fine, I have done the same thing many times to keep porch posts from kicking out on a slab where lift was not an issue. You can use bigger bar if need be also, I always used #4 (1/2") but you can get it up to 1"

[1988mustang]

Just wanted to thank everyone that replied.  Once again this forum has given me the support and ideas needed to complete my projects.  There is truly an abundance of information to be drawn from everyone here when I can't find my answers in previous posts.

Thanks.

[Bibbyman]

I never thought about frost heave being a problem with pole barn construction.  Down here it’s a cold day in ….. before the ground freezes more than a couple of inches.  Down here we worry more about the wind picking up a building.

[bandmiller2]

Mustang,first put sawdust or hay where the posts will go that will put the frost on hold for a wile. Clean down to bedrock and drill several holes with a hammer drill,rebar, set poles plumb and build a form around the pole and pour concrete.Be sure to cross brace the structure well. Frank C.

[paul case]

i was wondering how you northerners get by with concreting posts in. here in ne oklahoma it only freezes 6 to12'' deep every 3 to 5 years and we still have trouble with posts set in concrete getting moisture down between the post and concrete and freezing  and busting the concrete. i relize the poles in a shed wont get as much water down them but still this is a problem here where it dont freeze every year, so what about where it does?  pc

[Coon]

In Saskatchewan we can get grost up to 8 feet deep into the ground.  Most years it is four to six feet.  Normally around these parts we simply dig our post holes anywhere up to four feet deep but the deeper you can go the better.  In the bottom of the hole we put a bit of concrete and then set the post and fill with concrete to ground level.     
  Personally I would set my posts in sonotubes filled with concrete that sit up to 2 feet above ground level.  You set your posts closer to the outside of the sonotube so that when it comes time to put you siding on that you have less of an area to make up to bring the siding closer to gound level. 

[Bibbyman]

sgschwend:

 I probably should have stated earlier that my main concern was the poles kicking out from underneath the building.  To be honest my biggest fear is that my father will hit one of the front poles with the bucket of the tractor and the building will collapse.  It is kinda of a funny concern  but it does have real cause for concern. 

I was thinking,  if you have enough post material,  maybe double up on them for the first 4-6'.  This would give him something to bump into that maybe won't break or "kick out".

[flibob]

I know what you mean about your dad.  I wish mine was still tearing things up around here.  I guess I'll just have to help out my daughter more.

[Busy Beaver Lumber]

here is one other option to consider. Contact a local well driller. They usually have 8 inch and 6 inch diameter bits. You could have him drill you 8 holes for the main posts 8 inches in diameter, then have him go back with the 6 inch bit and have him drill 2 holes in front of each of the main posts and set concrete filled metal pipes in those to hole to provide protection for the main posts in case Dad get a bit wreckless with the tractor.

They usually get $8 a foot to drill and sounds like something that they could finish in about 2 hours. Might cost you a few hundred dollars, but a lot cheaper than having to rebuild the whole building if Dad knocks the supports out when trying to load a log

[sgschwend]

So you really have a soils question.  Shear strength of your soil, which will be based on how saturated it is and the soil type.

Certainly making sure the building has good shear strength can help a lot; then any shear the building goes under will be distributed around the build/foundation.

Also the larger the hole the better since the shear force is directly proportional to the area, you want the hole to take up a lot of area.

I am not that old but I too have a habit of smacking my posts.  Mainly my front gate which I have a habit of hitting with the rear end of a large truck.  A 6X6 post snaps off easily.  I am on my third, so perhaps your pop and I are related.

[r.man]

1.5 ft is a lot of strength for shear if the post will take it. If you are using hydro poles I would be more worried about the tractor. The bottom shouldn't move if hit and the top will transfer to the solid poles at the back. I would say that built that way you couldn't knock it down or pull it over if you tried with a normal farm tractor. Bad luck with the bedrock though. Around my area you always dig first because it might be close and it might not. Good luck with it and hope for a chinook.

[northwoods1]

I would never concrete a wood post in it will rot off in no time. It might be expedient but that is all. If your gonna pour concrete just set the post on the pad do not set it in the concrete. The well driller idea is crazy there is no well driller gonna come out to do a few feet of bedrock , beleive me they have a minimum charge and a good reason for it, and why would you want to? Get a well driller in to make some holes in bedrock so you can put a wood post in and backfill??? For a simple shed? Huh? 

[sdunston]

The last shed I put up I used those cardboard tubes in the ground 2 foot and left 2 foot above ground and bolted the 6x6 uprights to concrete, This way it keeps the wood off the ground and the loader forksdont do as much damange when ya hit them
Sam

[rbarshaw]

The snow will be here in Ontario in only a matter of days, and the pressure is on to get my sawmill shed completed.  I have decided to use old hydro poles to support the structure.  I had every intention of putting the poles 4 feet into the ground; however, mother nature has other plans for me.  I could only get 2 out of the 8 poles my desired depth.

Basically I have 2 corner posts in the ground at the back and need to get the others in VERY soon.  My problem is that for the other 6 poles I can only get down 1.5 feet at the most before I am hitting bedrock.  I'm not sure what  I should do to make sure the rest of the poles don't kick out and stay in place.

I was thinking of drilling a piece of rebar about 6 inches into the bedrock then drilling another 6 inches or so into the pole.   Set the pole on the rebar and brace the pole until the beam is in place and the rest of the building is in place.

Does any of this make sense?  I'm open to any ideas or criticism to better my ideas...  Any input would be appreciated...

Epoxy the rebar to the bedrock then epoxy the pole to the rebar, it won't move ever. Or epoxy a threaded rod to bedrock then make an angle iron pocket to bolt down and set the post in it and bolt the post to the steel, this would make it replaceable.

[laffs]

hammer drill holes in bedrock for rebar then form it up to about 3 ft for cement put your posts on top of the cement. same thing that isnt bedrock but go below frostline in your area might be 5 6 ft then put styrofoam around the cement so the frost wont grab the cement. but put the posts on top so if they ever rot get broke  you dont have to get them out of the cement

[Busy Beaver Lumber]

Northwoods

Wilth all due respect, your referring to the well drilling rig idea as crazy, may not be as crazy as you may think. I lived in the Apalachaian mountains back in NJ which was almost solid rock any time you went to dig for anything. In my area, putting a basement in almost always required drilling holes and setting explosives to break up the rock. A friend of mine owned a well drilling company and I worked for him part time on the side. At one time it was a pretty good business to be in, but with housing starts way down and more areas getting public water service, it is not the cash cow it used to be. It was not uncommon for him to have to send crews as far a 8 states away to get work and they would stay there for a few weeks at a time.

We were contracted many times to drill holes 3 to 4 feet down for fence post installations for horse corrals and pole barn style buildings. He would charge $20 a hole and we could drill on average 10 to 15 and hour. Would just leave the tower up and move down the line every 8 to 10 feet drilling the holes. At $20 a hole he was making between $200 to $300 an hour, which was a lot better than leaving the machine sit if he had no other jobs lined up for the day. His minimum charge was $300 per job. He actually got quite a few jobs after 9/11 drilling holes in front of office buildings and state and federal buildings for concrete filled metal poles for security reasons

Also you made mention that it is rediculous to drill a hole in rock just to insert a post and fill it in with concrete. It is not just an issue of having a stable base as a footing, it is just as much an issue of securing the building to the land. In many areas of the country, foundations and footing are subject to building department inspections and if they are not the proper depth or diameter you will not pass the inspection. Some areas also require the concrete to be tested and certified before the pour. Putting the posts in a hole with concrete satifies the building department regulations and also insures that a strong wind, such as a huricane, which is fairly common on the east coast will not lift your building and carry it away.

When you have to make the monthly payment on a half million dollar machine and the building industry is as slow as it is for the past few years, you have to get pretty creative and find ways to make the monthly payments or you can just sit back and watch the repo man come and drive it away.

[northwoods1]

When you have to make the monthly payment on a half million dollar machine and the building industry is as slow as it is for the past few years, you have to get pretty creative and find ways to make the monthly payments or you can just sit back and watch the repo man come and drive it away.

Busy beaver no offense intended

All I know about drilling wells is from having a neighbor that has been doing it for 20 years, and having had 3 drilled wells done on my properties over the years by 2 different local drillers one last summer at my farm. Here the way it works is no one comes out for less than 50 ft of drilling. I can see how your well driller friend may have been able to do it for a minimum charge.... but $300 would not be nearly enough for a driller to move and set up a rig like that it is more like $2000 for the average job and they can do more than one of those in a day if things go OK.

I beleive the best way to anchor those posts with the bedrock being so close to the surface would be to pour a concrete footing which the post will set on, but.... the footing has to be anchored to the bedrock and and epoxy like has been mentioned would be a very good way. A knowledgeable concrete contractor would most likely recommend the same thing.

[Kevin]

You can also buy rock mounts for poles or  build a crib below grade.

[Qweaver]

I would never concrete a wood post in it will rot off in no time. It might be expedient but that is all. If your gonna pour concrete just set the post on the pad do not set it in the concrete.

I don't mean to be rude but this is simply not true with treated posts.  I've pulled many posts that have been concreted in and in every case the posts were as sound as the day they were put in.  Hurricane Ike knocked down my rent house in south Texas in 2009 and when I pulled the posts they were still perfect where the concrete surrounded them.  Those posts were put in in 1979.  Same story with my two sheds that blew down.  One key is to keep concrete from getting under the post so that moisture can escape.

I would be comfortable with a few of the posts being 18" to 20" deep.  Especially if the hole is bell-holed, a piece of rebar through a hole in the bottom of the post and concreted for 12".  
Living in hurricane country, we do a lot of post setting.  My concreted posts stayed in the ground even tho' the buildings were destroyed and in fact I had to dig most of them out with a backhoe.

[Banjo picker]

 



I poured 2 ft sq colums ...set anchor bolts ...and bolted the base plates down...You can get or make an imbed to put in the concrete to bolt a wood post to as well...Tim

[redbeard]

I put my posts on poured blocks also, if you hit one at least you can swap it out. Concrete will rot PT post, especially if you trap the water!Your hard pan will trap the water also. It will last along time but it will rot eventually. The rebar will rot faster than the post and drilling the bottom will just invite water in for faster deteriation. If your posts are creosote like tele-poles or pilings By all means concrete away they will never rot. Our codes in our area don't allow rebar to penetrate ground it will decay and rot concrete (electraulisus)  is the main culprit.