New home construction.

[Bryan n Deb]

Hi there, new here. Found this place because of this older topic. 

We are planning a pole barn home on a slab. This is the 1st one in our township and the inspector seems unsure about the requirements for the slab "foundation" and insulation. When we started last year the old inspector said if the poles are through the frost level (42") you can just lay down a flat 4" slab. The new inspector seems to think it needs a foundation. Not finding much info online for this specific build. Plan as of right now. 4" radon pea gravel and barrier, 4" rock, 2" foam, heat tubes, steel mesh with 4" concrete over that. Someone here know the county (Isanti) spec for something like this? Township overrules county.  Thanks.

 

https://talk.newagtalk.com/forums/thread-view.asp?tid=376864&DisplayType=nested

Edited February 17, 2018 by Bryan n Deb

[PurpleFloyd]

If code allows post frame for residential construction then by design you don't need a block foundation. 

[Wanderer]

I think they’re more looking at the footings requirement, aren’t they?  Thus the reason for getting the poles below the frost line?

 

Its the township’s responsibility to figure this out and you have the right to ask them to cite the code they’re following.

 

I used to live in Isanti County and dealt with a building inspector from my township on the construction of my detached garage.  Things weren’t very strict to say the least.  

 

We built everything by the current UBC code, so I’d suggest first getting a copy of the current version of that since this building will actually be your home.  Don’t take unnecessary shortcuts to save a few bucks up front.  You’ll eventually regret it.

 

Reading your plans for the slab, it sounds pretty good.  There are plenty of slab homes out there built the way you describe.  What you don’t want is movement.  

 

I’m not an expert by any means but I think footings on your slab wouldn’t be a bad idea and sinking your poles that deep should be a requirement.  If you don’t do footings, at least pour your slab thicker on the perimeter to hold it better. 

 

Your local Authority Having Jurisdiction (AHJ) can be more restrictive than code, but not less.  So if it’s defined in the UBC, you have to do at least that much.

[PurpleFloyd]

Yes. But on a post framed building the only think I ever see is a thickened footing and not a foundation to the frost line. A major benefit of post framing is that you install the posts below the frost line so the need for a concrete foundation below the frost line is not needed. If I am understanding the question correctly. 

[Wanderer]

8 minutes ago, PurpleFloyd said:

Yes. But on a post framed building the only think I ever see is a thickened footing and not a foundation to the frost line. A major benefit of post framing is that you install the posts below the frost line so the need for a concrete foundation below the frost line is not needed. If I am understanding the question correctly. 

 

Sounds plausible to me.  Is the thickened footing in your mind the same as pouring the perimeter of the slab thicker?  We did an 8 inch perimeter around the 4 inch slab.

[PurpleFloyd]

Yep. That is standard procedure for floating slabs. 

[Bryan n Deb]

11 minutes ago, PurpleFloyd said:

Yep. That is standard procedure for floating slabs. 

 

11 hours ago, Wanderer said:

 

Sounds plausible to me.  Is the thickened footing in your mind the same as pouring the perimeter of the slab thicker?  We did an 8 inch perimeter around the 4 inch slab.

Im pretty sure we are going to pour the edge thicker but I can not find that it is required. I know we have to insulate down and out from the outside edge but cant find the specifics for that either.   Thanks

[Wanderer]

3 minutes ago, Bryan n Deb said:

 

Im pretty sure we are going to pour the edge thicker but I can not find that it is required. I know we have to insulate down and out from the outside edge but cant find the specifics for that either.   Thanks

 

Just my thoughts on that:

 

You’ll be glad you poured the edge thicker if you’re planning to stay there awhile.  A good, stable slab will reduce wall cracks and keep your door jambs plumb.  

 

And don’t skimp on the insulation.  My current home is slab on grade with in floor heat.  It has 2 inch insulation under it but not up the side of the slab.  I’ll eventually add that additional inslulation around the perimeter.  The ground is a heat sponge.  Heat migrates to cold no matter what direction it goes.  The insulation will pay for itself in a short amount of time.  The higher the R value, the better.

 

Good luck. It sounds like an interesting project.

[PurpleFloyd]

I would also look into using SIPS panels as an alternative to post framed. I have done a lot of projects using SIPS panels from a company called EPS in Iowa including the new fire station/ city hall in our town. 

 

The cost of the panels is higher than the material cost of post framed but they are super insulated, go up fast and really cut down on outside noise. Our city has saved a significant amount of money in heat savings and you can even put in smaller btu HVAC which saves money. 

[Bryan n Deb]

16 hours ago, PurpleFloyd said:

I would also look into using SIPS panels as an alternative to post framed. I have done a lot of projects using SIPS panels from a company called EPS in Iowa including the new fire station/ city hall in our town. 

 

The cost of the panels is higher than the material cost of post framed but they are super insulated, go up fast and really cut down on outside noise. Our city has saved a significant amount of money in heat savings and you can even put in smaller btu HVAC which saves money. 

Had looked into the panels and they pretty much doubled the initial cost of the structure. I could spry foam the entire wall cavity for less $ and have close to the same thing.

[Bryan n Deb]

On 2/18/2018 at 9:45 AM, Wanderer said:

 

Just my thoughts on that:

 

You’ll be glad you poured the edge thicker if you’re planning to stay there awhile.  A good, stable slab will reduce wall cracks and keep your door jambs plumb.  

 

And don’t skimp on the insulation.  My current home is slab on grade with in floor heat.  It has 2 inch insulation under it but not up the side of the slab.  I’ll eventually add that additional inslulation around the perimeter.  The ground is a heat sponge.  Heat migrates to cold no matter what direction it goes.  The insulation will pay for itself in a short amount of time.  The higher the R value, the better.

 

Good luck. It sounds like an interesting project.

Just had a call with the builder and the concrete guy I am working with. Neither said they would "waste" concrete on thickening the edge unless there were plans to add on to the structure at a later date. The builder said no amount of concrete on the edge will help the building stability. He says if it moves its his fault in building it. There will be no weight on the outside edge of the building, worst thing that could happen would be erosion outside the building.

[Wanderer]

So no sill plate for the walls on the perimeter then.  OK.  

 

Again, not an expert so whatever your guys say and you’re comfortable with... I don’t know all your construction details.

I - sandy County Is just that; sandy.  So it’s not too tough to get a good base.

 

My experience, as it relates to this, has just been based on building a 36x48 wood framed garage in Isanti County.  8 inch block on the perimeter to support 12 foot sidewalls of 2x6 construction.  My buddy that sold me the lumber said the project was only 200 feet short on interior walls from being a house.  After adding in the attic square footage it had more than my house.  Going with a pole building frame is the game changer.

 

Again, best of luck. It would be interesting to me to see the completed project.

[Bryan n Deb]

4 hours ago, Wanderer said:

So no sill plate for the walls on the perimeter then.  OK.  

 

Again, not an expert so whatever your guys say and you’re comfortable with... I don’t know all your construction details.

I - sandy County Is just that; sandy.  So it’s not too tough to get a good base.

 

My experience, as it relates to this, has just been based on building a 36x48 wood framed garage in Isanti County.  8 inch block on the perimeter to support 12 foot sidewalls of 2x6 construction.  My buddy that sold me the lumber said the project was only 200 feet short on interior walls from being a house.  After adding in the attic square footage it had more than my house.  Going with a pole building frame is the game changer.

 

Again, best of luck. It would be interesting to me to see the completed project.

I am no expert either but putting my trust in the builder. Talking to him, there will only be enough lumber to screw the sheetrock to. There will be no 16" on center studwalls. He has done several like this with no problems. The "Gurts" are attached to the poles and you could saw the poles off at the bottom and move the whole building.

[trolloni]

as you stated not finding much on this process online, you wont ,sure the infloor heat is good and works if installed properly and a boiler is used not a water heater ,but what is going to stop the frost from getting under the slab from the outside perimeter of the  building ? you have to have a "cold break "  at least 42 inches  deep

[trolloni]

Another thing you are forgetting  you bury wood its dinner bell for termites treated or not , unless you use the new concrete post underground ,how much experience  does youre builder and concrete guy have ?  they also say no amount of concrete will help stability , I hope you misquoted him but that is nonsense