Concrete foundation without a cement truck

[Little_Grizzly]

We are planning a new cabin in the mountains. The existing cabin has been there almost 90 years now. The issue with building a new cabin is the footings. Is it possible with enough people to pour a concrete foundation with nothing more than a mixer and piles of ready mix? There is no way on earth a cement truck could make it to the site. There is about 9 miles of serious off-road to get there. Might be able to drag one in with a dozer but it would be dicey.

Is there any solution for the situation where cement trucks just can't make it?

And before I get a slew of "...no inspector would ever let you...." or "..building codes require..." This is unincorporated land and no building permit is required. Doesn't mean I don't have signed drawings or don't care about code. I'm just saying that limitations on pouring by hand that are based on legal issues are not relevant here.

Griz

 

[CADplans]

Is it possible with enough people to pour a concrete foundation with nothing more than a mixer and piles of ready mix?

Look what they did in Egypt a few millennia ago,,, with enough people.

How deep is the frost line?
Have you considered simply drilling, and installing pilings for the foundation?

If I were to do a remote cabin, it would not have a poured concrete foundation,,

 

[RedNeckRacin]

If you made your forms small enough I suppose you could mix and pour with a hand fed mixer. Ideally if you had two or three it would go pretty quick. My question is like the previous poster, why?

 

[ArlyA]

We had a bridge to do where we moved in 100 bags of premix to and poured two bridge abutments. We could not get a cement truck to this job. Each of the abutments took 2 pours and we moved the premix in via UTV trailer. The footings were 2ft wide and 12ft long. Each pour took about 4 hours to mix. Does that help?

 

[rhunt]

I see no reason why you couldn't, if you had enough (6) men. You could do it in shifts and make it easy an all. Bob

 

[Little_Grizzly]

Thanks for the fast replies! Let's see if I can answer questions.

How deep is the frost line? Ans: This is California so frost line isn't really a concern around here. Probably an inch at the worst ha ha. The soil condition in general is sandy/rock. You could not ask for a more stable soil. The existing cabin is sitting on a 4" x 4" "foundation" (using the term very loosely) and has stood for 90 years with only one crack. I will be building a larger structure however.

Have you considered drilling/pilings? Ans: Not seriously but maybe that isn't all that bad of an idea. I'll have to do the calcs to see how many I would need and the spacing. Digging in that rock isn't something I would look forward to but at least it can be done with a small crew.

RedNeckRacin: I was thinking exactly on those lines. Maybe three or four mixers and I think I can get about a dozen workers. This will be a 25' x 50' structure. The current plan was 8" x 16" footing. That's around 5 yards ish. I've seen those 1.75 yard towable mixers. Maybe two of those gets the job done if we can feed it fast enough.

Feel free to tell me I'm crazy. It's happened before. :laughing:

 

[Little_Grizzly]

ArlyA yes that helps! What I didn't plan on was having a couple of dogs to round out the crew! great choice!

 

[dfkrug]

For a perimeter footing of only 5cy, it is very doable if you can haul the equipment
and materials into the site. If you can get a tractor in there, consider a tractor-mounted
PTO mixer. I have done numerous pours of a yard or 2 without any help at all.

My Mixer80 is rated at a bit under 1/3 cy per load. Those small electric mixers are
usually rated at 1-2 cubic FEET per load.

There are also the 1 cy trailer-mounted mixers out there. Loading them is what
you need to plan for.

 

[GLyford]

Instead of pouring all the walls, you could pour a footing, then stack blocks. Either dry stack and use the one of the outside bonding agents like quikcrete "quikwall", or just use a regular mortar. Then backfill the cores if you want the extra strength...either just at corners and occasional piers along the walls (especially where joists will sit), or in every one. Depending on height, you will probably want to drop a chunk of rebar in some of those.

The biggest advantage I can see of doing this over a formed pour is that for a formed pour, you need to make up bigger batches (or set rebar, or have "keys" in your forms between sections for tying wall sections together). The smaller the batches you need to make and the less concrete you need to get in place all at once, the easier it will be, particularly for one or two people.

If you have a lot of loose stone, you can also "cheat" regular form pours some by dropping in stones until the concrete level is up to where you want it (I would probably stick to short sections of wall if I did this, like 4 or 6 feet). Had an uncle who did this while also digging out the basement by hand with a wheelbarrow...in his 80s. Dig out out, shore, form, pour, add stone, go back to digging. I think he was finding the stones as he was digging.

Sometimes you can also do a "climbing" or "rising" form, where you have the form set 1 or 2' high, pour, let set, strip, and reset another 1 or 2 feet until you get up to the wall height you need. It's still doing a wall in sections, but vertical rather than horizontal.

People did all of these by hand before there were concrete trucks, particularly during the post-ww2 building boom.

If you have access to gravel and sand on site, you don't even need to bring in full blend concrete mix, you can haul in a smaller amount of portland cement and mix up your own. You can count shovels full (1 of portland, 2 of sand, 3 of stone for a basic mix) or you can make a box form about a cubic foot square (one 94# bag of portland is one cubic foot, so easy multiples like a full or half bag make counting easier). You can make a mixing surface to use with hoes and square shovels out of a couple sheets of plywood (or mix in a mortar tub or a wheelbarrow) if you can't get a mixer and generator or gas mixer there.

Making a whole foundation from bags is a lot of work, but very doable if you break it up either by breaking the project into segments or by adding more bodies so the individual workload is still reasonable.

 

[GLyford]

Oh, and more on the suggestion of "piling" foundations: A hole dug with a post hole digger, with a chunk of sonotube sticking up for the part above ground. (If frost will be a big issue, a smooth sided piling from a sonotube all the way down would be better, so the frost doesn't "catch" on it and lift...no frost, dirt sides is fine).

 

[Egon]

It can be done. Just takes work.

In the not too distant past building foundations/floors etc. The materials were mixed on site. I've seen it done. Aggregate hauled in with horses and wagons before hand. Cement mixer running off a small gasoline engine. Just sacks of Portland. No ready mix at that time. Water likely pumped by hand and carried in buckets. Just hard work!

 

[Snobdds]

Two summers ago I started my cabin, it too was where no cement trucks could get to. We had an electric cement mixer and 250, 80lbs bags of concrete. We planned to spend 1 entire summer just on the pylons. We hauled 1 pallet of concrete at a time, 50 bags, and were able to get 1-2 pylons a weekend. It was some of the hardest work I've ever done. The result was rewarding.

Just jump in and get it down. That's what I did...

 

[Snobdds]

Here's another angle and right before the snow started...

 

[Little_Grizzly]

Those are some pretty skookum looking piers Snobdds! Making me re-think the pier vs. poured foundation question.

 

[oosik]

When we built our cabin in Alaska - I never considered a complete foundation. We dug strategically located holes to a depth well below the frost line and mixed our own cement on site and filled each hole, one at a time. We jammed a 12" diameter sono tube into the wet concrete and adjusted it to bring it to an "on grade" height and filled the sono tubes with cement. After we were done and the cement had hardened for about 40 days we started the building with 18" diameter logs - two sided to a thickness of 14" as the sill joists and went from there with logs for the remainder of the cabin. Our cabin was quite a ways out in the bush - being about 45 miles SW of Palmer.

 

[Snobdds]

Those are some pretty skookum looking piers Snobdds! Making me re-think the pier vs. poured foundation question.

Pylons are the way to go for a cabin. That way you don't have to do the entire pour at once and it can be broken up into pieces. If you have any deep snows in your area, it helps to get the cabin off the ground. We get 10+ feet of snow, so being 4 feet off the ground helps so much with snow depths.

 

[quicksandfarmer]

Some thoughts:

Figure on 3,000 pounds per yard, so five yards is 15,000 lbs. That's 250 60 lb bags. My Home Depot has them on sale for $2.17/bag if you buy a pallet or more, which is cheaper than the price I could get from a truck. It's also cheaper per pound than the 80 lb bags. I prefer the 60 pounders because they're easier to handle.

Foundations are usually done in what's called a "monolithic pour." What that means is that at the end of the job you have a single piece of concrete. Cured concrete doesn't bond well to uncured concrete, so time is of the essence when doing a monolithic pour, once you start you can't stop. If the concrete already in the form has hardened before you add more concrete you get what's called a "cold joint" which can be a weak point. So you need to either plan it so you can work uninterrupted, or figure a way to break it into separate job. I would say that 250 bags is a lot to do all at once, especially if you aren't experienced. What happens if your mixer breaks down after 100 bags?

Look into piers. It's a big advantage to be able to do them one at a time. If you have stamped plans your engineer should be able to tell you if they're feasible with your soil, how many you'll need and how big.

The other thing to think about is how you're going to get everthing else that goes into the cabin there! If your cabin is 1250 square feet, a rough guess would be 20 pounds per square foot for the materials to get it closed in, or 25,000 lbs. That's a lot to take in small loads.

Keep us posted, these kinds of projects are fun.

 

[Little_Grizzly]

Differential settling would be a concern wouldn't it? I mean if you only loaded some of the pylons and then in later years loaded the others wouldn't the settling be uneven?

 

[Streetcar]

You can pour the foundation using bag mix and use construction joints between segments.
End one segment with keyway and some rebar. Joints are used in many foundations

 

[Redlands Okie]

Ok I know I am going to catch some flame for this but am going to say it anyway. When i read "footer" or "foundation" i am thinking at or below grade. Why can you not pour in a dry mix right into the footing ? Adding some water and mixing it really well in the footing if you can would even be better. Believe it or not the dry mix will absorb water from the surrounding soil over a period of time. Please note that the stiffer you mix concrete (which means using less water) the stronger the end result will be. Excess water is a major no no. A shovel and mixing it really well in the footing as you pour it in fits this stiff mix requirement just fine. The concrete blocks on top of the footer suggested above will work just fine. Some may or may not agree with this idea but just to keep it short i do know a bit about what i am talking about.