Instead of a concrete slab

Around here we use a product called Sonotubes, cardboard tubes about a foot in diameter.You dig a hole where want a post set the tube in and fill it with rebar and concrete.it might work well for you.

if you are worried about heaving, you either need to anchor the building to soil below the frostline that will not heave, or you need to find a way to make the building float on top of the heave and hope it heaves evenly. chances are that as small as the building is, it wouldn't heave unevenly too much.

the easiest thing to do would be to use gravel and set the building on concrete pads like you use for a walkway. i like the idea of using timber to contain the gravel as it would tend to push out sideways over time. the timber would contain the movement of the gravel and prevent some of the settling.

either pressure treated piers, locust posts or concrete piers would work if you decide to use piers. i would sink them in at least 36 inches and have at least a foot above ground. you need to find out what depth the frostline is in your area. i would sink piers into the the area below the frostline at least one or two feet. someone with an auger could drill the holes and you could plant timbers or tubes for concrete. i'm thinking 8 inches would be a good size for the tubes.

the building will be your residence, so i think it would be a good idea to anchor the building to the footing. you wouldn't want to be like dorothy and end up in "Oz" due to strong winds. anchor bolts set in the top of the concrete piers could be used to bolt the building down.

the piers, or whatever, should also be supporting the building at places where it won't break apart. i would think you want a band of timber on the piers, or you want the building not to set in such a way that part of the building's frame is not supported. i have no idea if the building has 20 foot timbers under it (solid) or if it is made of shorter pieces. you would want a pier to be totally on one timber and have another only a few inches away. comsidering that, a gravel pad is a good idea as it supports the entire underside of the structure, but then you need to find another way to anchor the building.

you have a lot of homework to do. i wouldn't want to just slap this together if i were going to stay there for a few years.

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this message has probably been edited to correct typos, spelling errors and to improve grammar...

"All that is gold does not glitter..."

Something they do in Alaska is to level the site put down a few inches of rigid dense foam insulation and then build on top of that....no foundation at all.

AngieM2, yes, same idea. I'd forgotten about sancraft doing the same thing.

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I cried because I had no shoes, until I saw a man who had no feet.

I'll go a little different that some of the other ways. First, I'd put down a short layer of sand and level it. Then I would put down two 20' long pressure treated (rated for ground contact or underground) 4" x 4" runners, spaced the 12' apart on the outside edges, and three runs of corrugated 4" drain tile, equally spaced between them..

Next I would build up the sand around the runners and drain tile (mixing in about four pounds of boric acid to the sand for insect control) so that only about 1/2" of the runners was exposed and clean of sand. On top of each of those runners, I would lay an oak 2" x 4'' preservative treated board on its side, not nailing or attaching it in any way. Next, I would lay a barrier of either EPDM rubber (preferred) or two layers of 6 mil black builders plastic, covering the entire area with an excess foot on each side.

Then I would make my two primary support beams rest on the plastic and then the runners, but I would curve the bottom of those beam ends and the 2"x 4" below them to the shape of the front of sled runners, and lag the runners and beams together. The two beams would be cross-braced, insulation dropped between them, then 2" x 8" joists used to support the floor as normal. More insulation or perhaps radiant heating, or ducts would go in this area as well.

The ends of the the EPDM or plastic would be pulled up and stapled tight. This method of construction forms a virtual boat, providing the EPDM barrier isn't broached. If a time comes when the building needs to be moved, it can then be pulled like a chicken tractor to the new location.

Plumbing drains and water pipes wouldn't be a big issue if the area where they pierce the seal is open enough to work and apply the appropriate patching.

Now there you go!

Build the first section with other sections in mind. I'd make the walls several feet higher.... so you could stretch your roofline down. Add modules as money allowed.

If money is an issue, realize that flooring and roofing are some of the major costs in a home. You could build a two story home, for only a couple hundred more bucks for the second floor framing. And it's usually warmer upstairs. I doubled the size of my home, for around 400$ extra.

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Luck is what happens when preparation meets opportunity. Seneca
Learning is not compulsory... neither is survival. W. Edwards Deming

If you aren't committed to the amish shed, fordy and texican have given you some extremely good advice. I encourage you to consider it carefully.

The single most expensive system in any northern house is the foundation. Build up, whenever you can.

If your handy at all I'd avoid the "Amish" shed all together. You can build it much cheaper yourself with better materials. For instance if you were to get "barn boards" the lumber would cost less than 2 grand and it will out last your grandchildren without paint.For instance I build my 10X16 barn for about 1200 and that included the tin roof that cost $250. Your not that far from me so prices should be about the same. You will need a foundation of piers at least if you don't want frost issues. Spend the money on foundation... it's worth it in the long run.

Isn't their a bible passage about the house built on sand?


Let me know if you want some info building the shed from scratch. It really isn't a big deal. I will even make you a material list for price comparison if you would like. I worked out a "cabin" plan. That we will be putting on the back side of the property one of these days. It was 16 x 12 with a loft for sleeping, a kitchen/eating area, and a bed room. It had no provision for a bath but one could easily be added. I figured it would cost about 2500 +/- 10% for materials.

Thanks for all your help and advice. While I consider myself to be quite handy, I will not kid myself into thinking I could build a cabin. I'm a 51 year old woman who works 2 jobs, and have goats, poultry, a horse, garden, etc., so time is a big factor. Also, this will be the 4th shed I've purchased in a space of 7 years, so I know the quality of materials and workmanship. I'm confidant that I can do the work necessary to have a comfortable living space, I just need advice on the foundation.

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I cried because I had no shoes, until I saw a man who had no feet.

just remember you are in a cold zone..so you do not want cold winds blowing under your home..just plain too cold to heat that floor..so at least bank up around it.

Will you please post photos as you go?

I bet it will be as cute as that little shed someone fixed up for a 'playhouse' in her backyard. (A thread in Melissa's forum.)

Angie

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"Live your life, and forget your age." Norman Vincent Peale

Okay, one more time. IMHO, you really don't need any type of foundation for this "temporary" building. I agree with some of the others that a bed of gravel would be beneficial to act as a "shock absorber" from frost heaving. Then, treated timbers or concrete blocks on the gravel to keep the building off of the ground. Our 16x24 cabin has insulation between the floor joists that keeps the floor nice and cozy warm. (There is over a foot of open air space below our cabin floor).

Just remember, this building is equivalent to a garden shed. How many garden sheds do you see on piers, posts or footings buried to the frost line?

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This is the government the Founding Fathers warned us about.....

20 feet is pretty long for a garden shed. some of the amish designs i have seen in that size or larger are called "barns" (yeah..i agree, but that is what they are listed as). a 20 foot building has a lot of weight. unless it is sitting on pontoons, there is a good chance it will begin sinking in the spring thaws. we can have several of those per year in our climate. so, if one would choose to set the building on the ground, i would advise to prepare to level the building every year or so. gravel would help prevent some of the sinking, but it won't prevent the heave. again, 20 feet is a long span with so much weight. if it heaves evenly...fine. if it doesn't, no one minds stuck doors or cracks in a shed, but in a home?

i was serious about anchoring the building...you never know when the weather will turn. just make sure you pay your "lollipop guild" dues and get your "yellow brick road" kicks all shined up.

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this message has probably been edited to correct typos, spelling errors and to improve grammar...

"All that is gold does not glitter..."

"Isn't their a bible passage about the house built on sand?"

I was kinda thinking more along the lines of Noah's Ark.

Another consideration that may affect how you support this building is your county zoning ordinances. Where I live, any structure similar to the one you're thinking of....that is "permanently" attached to the ground with footings, concrete slab, concrete piers or treated wood posts....is considered a dwelling and is taxed as such. In addtion, a building permit must be obtained and building codes must be followed. In some jurisdications, this type of "permanent" structure may even be required to have sewer, water and electricity.

"Temporary" or moveable structures like garden sheds or play houses...sitting on wood beams, gravel pads, or concrete blocks...do not come under the same zoning and taxing requirements.

Just something to think about and research in your own county.

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This is the government the Founding Fathers warned us about.....