Foundation Question

[Archena]

Re: Foundation Question

Hi guys,

I don't know about ready mixed - I don't even have land yet so accessibility is an unknown. I'm sure it'll be on a septic system so big trucks are likely out of the question. Worth looking into but I'd have to rent a truck as well - a Corolla ain't pulling anything heavy.

Thing is, I've got to have enough energy left after pouring the concrete to get the rest of the job done. I dunno but I'll have a lot of time to think it over and look into the options before I have to commit to a single plan.

Thanks!

[ihughes]

Re: Foundation Question

I feel very lucky after reading what some people have been up to.
After I framed my slab I phoned the local concrete company and around came a truck and backed right up to my form and poured. I leveled it off and 30 minutes later was back inside having breakfast. And it was cheaper than buying the materials and mixing the concrete myself.

The concrete company I used has a .6cu m minimum pour which is just about right for the standard slab. Some companies for a fee can pump it to where you need it if access is a problem (of course this will cost extra).

This is in Australia, of course, so I'm not sure what services you might have available where you're living. But I can recommend getting someone else to do the mixing.

cheers
Ian

[jahysea]

Re: Foundation Question

Archena,

If you can buy the concrete ready mixed (US Rentals) and are able to put the trailer anywhere you need to drop - it should be a slam dunk....

Hi, I'd have to agree. It only took me about 20 mins to wheelbarrow all the concrete from the rented mixer to the slab. I took big loads, so allow a little more time if you can't handle a full wheelbarrow of concrete.

The time consuming parts were finishing the slab and cleaning the mixer. Both things seem like they need to happen at once and take a while.

If I had it to do over I'd spray a bunch of water in the mixer after filling the slab and then go spend my time trowelling the slab before worrying about the mixer.

Note that you need a serious truck to rent the mixer I had. No small Toyota pickups or cars with hitches....

[Les]

Re: Foundation Question

Archena,

If you can buy the concrete ready mixed (US Rentals) and are able to put the trailer anywhere you need to drop - it should be a slam dunk. When you screed the mud, it doesn't have to be perfect or finished. The rest of the work is just labor, you can take your time. If your forms are not perfect, you can mortar the block to get them level. In my application, I knew that I would make all things right when I got to the top of brick. The fact that my foundation and dry stacked bocks were not exact did not matter, no one will ever see it.

Go for it - little cost, and you WILL save a lot of time.

Hope this helps,

Les...

[Archena]

Re: Foundation Question

My biggest concern is the duration of the pour itself. If I'm going to have to do it I need as short a time frame as possible simply because I physically can't last very long doing that kind of heavy labor. All the other components can be done a little along but once concrete is wet your working time is limited and you have to do it all then. You can't pour concrete in phases because it won't bond to itself - it's all or nothing. A small slab is still a lot of work - so if it has to be a slab I'll have to hire someone to do it.


And I don't wanna hire someone - I wanna do it myself.







Yes, I'm slightly insane - why do you ask?

[Balty Knowles]

Re: Foundation Question

Just for my 2 cents worth. Go with a slab, the additional work on the forms, although less back breaking, I think would be more than moving the extra dirt & over all the slab is better. Still, I feel your pain, I moved over 12 yards of dirt up hill for my whole project all by hand plus I discovered a dissused sceptic tank I had to fill. It was the worst part of my project & there were several times I considered filling it all back in & planting lawn, however, now that it's behind me it was worth it.

Rgds

Balty

[Les]

Re: Foundation Question

I?m not worried about mine falling down ? I?m worried about it sinking into the earth. I had no appreciation of the weight involved until I started hauling concrete, blocks, and now ? 750 brick. All this before I start the oven.

[dmun]

Re: Foundation Question

Hey Drew,
I don't think you can ever tell if something is over-engineered; you can only tell if it was under-engineered -- and falls down. :-)
James

It's said that anyone can build a bridge that can stand, but it takes an engineer to build a bridge that will just barely stand.

[james]

Re: Foundation Question

.....All friends involved (including 1 home builder) say this is overengineered, time will tell...

Discussion of this is located here:

http://www.fornobravo.com/forum/f6/mailbox-pompeii-colorado-472.html#post2598

Drake

Hey Drew,
I don't think you can ever tell if something is over-engineered; you can only tell if it was under-engineered -- and falls down. :-)
James

[ihughes]

Re: Foundation Question

If ease of building is a consideration then I found a slab very straightforward.
Dig a square hole, frame it, reinforce and pour.
I took a lot of care to get the framework square and also to square off the concrete using a 2m length of 4x2 with a straight edge. Now I've got my cement blocks dry stacked and everything is square.
I don't know what Alabama weather/soil is like but a slab is pretty much fool-proof.

[dmun]

Re: Foundation Question

Seems to me that pouring a slab is serious overkill. Thus I'm asking if I'm way off base here. How about this thought: Excavate the site (to remove the grass) and put a layer of sand down similar to that prior to pavers. Then use cinderblocks with a flat side down to form the "slab". Add cinderblocks on top of that until the desired height is achieved. Place a sheet of durock on top of the cinderblock pile, and pour the vermiculite concrete directly on top of the durock.
If needed the cinder blocks could be mortered together or use the "fill the holes" technique. Once the weight of the oven is there, I'd suspect nothing is going to move at all. At about a buck 50 a cinderblock plus the labor savings, wouldn't this be sufficient?

What am I missing?

OK, lets see. You're in New York, so you have a frost heave situation. There's two ways to deal with frost heave, and easy way and a hard way. The hard way is to dig down to below the frost line, which would be (guessing) 36 inches in long island and fourty two inches in buffalo. Then you pour a one foot thick footing six inches bigger in every direction than your structure. This is the way you need to go if your oven is built into a structure, like mine.

There is an easier way if your oven is free standing. You avoid the frost situation by laying down six inches of compacted crushed stone. This drains off standing water, and frost doesn't accumulate in the absence of water. You need to have a well drained area for this to work, and a significant slab to even out small changes in the soil.

So the bad news is that the slab is the easier way. Methods of supporting ovens, without significant masonry structures, depend on significant welded steel structures, not a single sheet of wonderboard, which cracks when you look at it. Ovens are heavy, and rigid, and hot, subject to thermal changes in dimension and cracking. Any time and money spent in preparation is well spent, in my opinion.

[wlively]

Re: Foundation Question

I am sure the professional engineers could chime in here, but I would have reservations.

IMHO: Footings are fine. In my case a whole slab was cheaper and easier than footings and pavers ($100 for a dump trailer filled with 1 yard of concrete). I have a paver patio. But you are talking a serious amount of weight. Too much to be resting on individual blocks that are not structurally tied together. Even well done pavers with no weight but humans and furniture sometimes shift a bit. Rough guess 200 bricks (8lbs * 200 = 1600) plus 23 bags of concrete (23*80 = 1840 lbs) plus rebar (30 lbs) plus 3 50 lb mortar (150) plus roof, framing, and walls ( 640 lbs) , which adds up to 4,260 lbs and I know I am missing something.

Durock is fine for the floor of the hearth form, I used it myself. If you mean solid square of cinder blocks with no opening, then that would probably be OK. The insulation concrete is very brittle and crumbly and is OK only in straight compression. You would need at least a ring of conrete around it to hold it together.

[wg_bent]

Re: Foundation Question

Seems to me that pouring a slab is serious overkill. Thus I'm asking if I'm way off base here. How about this thought: Excavate the site (to remove the grass) and put a layer of sand down similar to that prior to pavers. Then use cinderblocks with a flat side down to form the "slab". Add cinderblocks on top of that until the desired height is achieved. Place a sheet of durock on top of the cinderblock pile, and pour the vermiculite concrete directly on top of the durock.
If needed the cinder blocks could be mortered together or use the "fill the holes" technique. Once the weight of the oven is there, I'd suspect nothing is going to move at all. At about a buck 50 a cinderblock plus the labor savings, wouldn't this be sufficient?

What am I missing?

[Archena]

Re: Foundation Question

Coolness!

We don't have much of a freeze/thaw cycle here - three inches of snow will shut down the whole state because it snows so rarely. Block walls are probably more reasonable for me - that and I want to avoid concrete trucks as much as possible. I plan on moving to a rural setting and a septic system will not be optional. Big heavy things are not good for field lines so unless I'm really sure the truck can easily avoid them, wheel barrows rule.

This is exactly what I had in mind for the floor of the stand. Looks really good, too! Great job there!

Thanks much!

[DrakeRemoray]

Re: Foundation Question

Hi Archena,
I did not use block walls, but poured concrete walls into forms and dug 4 sonotubes for foundation support. I have heavy clay soil and a freeze thaw cycle here. All friends involved (including 1 home builder) say this is overengineered, time will tell...

Discussion of this is located here:

http://www.fornobravo.com/forum/f6/mailbox-pompeii-colorado-472.html#post2598

Drake