Cement depth under evaporator

[markcasper]

I am planning a new sugarhouse this summer or fall. Looking to build 40 x60 plus either a seperate wood storage area or attached, or lean to. Am still tossing the ball on that one. I don't expect to be boiling there in 07 as I am not going to rush anything and I am planning on doing the interior walls and some electrical myself. And then you have the cost too, but would like to get it up before prices go even higher!

I was thinking of upgrading to a 6x16 or longer. I am contemplaitng an R.O. as well and just keeping my 4x12. The drawback to an R.o. versus a larger evaporator is the cost. Usually those big evaporators bring much less than a 4x12 in good shape.

Anyhow.....Is it recommended to have a good footing under an evaporator of this size and what about cement depth??Or can it just be the same as the rest of the sugarhouse and doesn't matter much.? Mark

[LincolnWoodsLager]

Wish I knew! Also looking for advice on this topic. Planning a smaller sugarhouse to build this summer - will definitely be boiling in 07. Will house 2x6 or smaller. Any advice on how big the concrete slab should be, and depth? Also does slab need footings that go below frost depth? Any thoughts or recommendations would be helpful. :)

[Maple Hill Sugarhouse]

post edited

[maple flats]

Yes, the north American Maple Producers manual states that the footers should go down to either bedrock or below frostline whichever is less. You do not want the frost to heave the rig, and would likely do it during the sugarseason since that is when the frost is coming out of the ground, most heaving happens then.

[forester1]

I put footings 4 feet down under the evaporator and then put expansion joint around those when I poured the rest of the floor. The floor moves a little but the evaporator stays level. For a 4x12 I put a 5x5 section under the front and two 1x5 piers under the back and middle legs. Maybe a properly designed poured floor would work but I poured the floor myself in sections and didn't have sand trucked in to build up the grade.

[royalmaple]

With proper drainage and compacted sand under the slab I don't see why you would need footings under the slab. Footings typically are for walls to support the weight of the building and so the walls don't shift all over. Most slabs are poured independently of the walls and are not pin'd to the walls so they are considered "floating slabs", they may shift a bit, but have you ever gone into your basement and seen mountains? You will get cracks no matter what you do or who pours it. If the substrate is compacted well and you have good drainage I don't think you will have the problems that would warrant footings under the slab.

If you had lolly columns under a carring beam then you can make a cow patty pad for them under the slab for extra support.

Personally I spend more money on better perimeter drains and good sand compacted in lifts than dumping more crete under the slab. 6 inch slab should be pleanty also, if you wanted ..haunch the sides. add fiber to the crete, and wire mesh inbeded in it.

[Sugarmaker]

We went with a concrete footer and block foundation under the arch area. Two reasons: I set the arch before I had the floor poured the next year. I always do things the hard way! :D I made the pad for the arch big enough that I could go 1 foot wider and 2 feet longer (evaporator size) if I wanted to. Also poured cement pillars for the four legs of the evaporator. I had them put extra cuts in the poured floor to minimize cracking. 5 years and no problems yet. I have seen the edges of the floor move 1 inch but the evaporator hasn't moved at all. I think it was worth it to build the foundation. We have very poor (wet soil) drainage and see a lot of frost heaving.

[ennismaple]

The key is to get good drainage. Make sure to put in 4" or 6" Big-O in a filter sock around the perimeter and a couple of runs under the middle of the slab to keep water from building up. I'd use 3/4" clear stone (no fines) under the slab.

It's differential frost heave that you're concernced about. Unless you're prepared to put in 4 feet of stone or sand under the slab you can't prevent the slab from moving - you just want to make sure it all moves the same amount.

[hintonsugarshack]

I put 2" blue bord insulation under my cement I saw it done on a house with radiant heat so then I got the idea to stop the frost from heaving my cement I insulated in so it cant freeze It has been 3 years and no cracks :lol: :lol: :lol:

[Fred Henderson]

I know a guy that was building a garage. He put 2" of pink board under 6" of concete and left it all winter and it never moved, cracked or anything. The following year he built his grarage on it.

[mcmp]

We can get a lot of water run off from the mountains. With this in mind, to preclude a frost heave problem, when I built my present sugar house I dug down about 4 feet with my back hoe. First I layed 4 inch drains all tied together and feeding a main underground drain. I then covered the drains with road stabilizing fabric, then 3 feet of shot rock, another layer of road stablizing fabric, 1 foot of Item 4 and finally 3 inches .750" white marble chips. The Evap is sitting on a 6 inch concrete slab with a 4 inch square re-bar grid. Given our serious winters where temps can go to 40 below and drive frost in, I have never had my evap move off level in any direction. She is just there for the count.

Paul

[markcasper]

Thanks for all of the interesting comments! Always best to turn to others who have been there. We are on pretty high ground where I am and where the shed will be built. The ground is pretty light, sandy loam and very heard sandtone underneath. When our house was built a few years ago, the excavator commented that our site was one of the harder basements he had ever dug.

In my current building there is nothing special, just 6 inches of concrete with no footing or anything. I have never noticed the evaporator to move yet, so ??? Mark