Ok to pour wall in multiple shifts?

[JackOfDiamonds]

I'm thinking about building a house addition. I could pour the footer and foundation wall myself with quikrete if I could break the job up. Is it ok to do that as long as you have rebar to tie the sections together? And is it better to pour all the way around 6 inches at a time, or pour full height a few feet at a time?

 

[cvairwerks]

Simple answer is no......The more joints you have in a pour, the weaker the finished product. Large walls are done via continuous pours, in approximately 6-10" lifts, to allow proper entrained air removal and form filling and to reduce the chance of a blowout.

For quick estimating, a yard of concrete will do about 70 square feet of 4" thick flat slab, which would require 45 bags of quickcrete. A pony wall of 8" thickness, 24" high and 120" long, is about a half yard of volume. Quickcrete has a set time of an hour or less, and once it starts setting, structural complete joints are near impossible.

A good crew can come in, form, lay rebar, pour and finish the complete foundation and the walls in just a couple of days.

 

[mike93lx]

You'll end up with cold joints.

Putting aside the action of mixing, do you have the skills and tools to do this at the equity level it needs? If not, hire it out, but regardless, get the concrete from a truck

 

[PCustoms]

No, not OK.

Also, a wall is a lot of concrete. What are you using for forms? Why not have a truck?

If you need to diy have you considered block?

 

[billconner]

Is this a footing and short stem wall for a slab on grade foundation? Certainly you can pour footer separate from stem wall.

How un-balanced is the wall? If it's filled on both sides except for top 10 inches or so, I don't think the risk is high. So many buildings around me on dry stone foundations, not sure it would be so bad.

I built my garage on rubble filled trench's to below frost, laid block on that, and surface bonded. Four years and no cracks. And no leaks on side dug into a hill, about 4' below grade.

Basement wall or unbalanced more than 10 or 15 inches and my answer would be different.

 

[JackOfDiamonds]

It's a footer and stem wall for a crawlspace foundation. I could pour the footer and use blocks for the stem wall.

The smart thing to do is hire it out. But with the trades in my town being what they are, nobody has any time for small projects. Once company find out what I'm trying to do, they don't even answer the phone.

 

[Rc_Guy]

It's a footer and stem wall for a crawlspace foundation. I could pour the footer and use blocks for the stem wall.

The smart thing to do is hire it out. But with the trades in my town being what they are, nobody has any time for small projects. Once company find out what I'm trying to do, they don't even answer the phone.

Isn’t there any guys that’s do it daily that do it on the side?

 

[PCustoms]

It's a footer and stem wall for a crawlspace foundation. I could pour the footer and use blocks for the stem wall.

The smart thing to do is hire it out. But with the trades in my town being what they are, nobody has any time for small projects. Once company find out what I'm trying to do, they don't even answer the phone.

How big of an addition?

What "red flags" are you throwing up that lets them know what you're doing and makes them not answer?

 

[rooster59]

Have helped pour a couple with friends, do you have some type of mini-batch in your area? We had about 4 guys with shovels, wheel barrows, etc. Provide refreshments & KFC. Plus I’ve always felt quickCrete was shy on the Portland cement.

 

[Hank11]

You might also compare the price of equal amounts of bagged and truck mix.

But keep looking for a small time guy who wants some work. Sometimes the word “cash“ helps.

 

[PopcornSutton]

Since it's a crawl space wall, it isn't so bad. You talking about 2 feet high? If you make your forms right you could strip and move them for the next section. If you had rebar going horizontal from one pour to the next is a start. You could also put a keyway in the joint face to further lock the joint. One more step would be a bentonite waterstop between pours would help leakage. Put rebar in your footings that extend through just like the wall. Dowl in some verticals in the footing into the wall. There is always a way.

 

[JackOfDiamonds]

Since it's a crawl space wall, it isn't so bad. You talking about 2 feet high? If you make your forms right you could strip and move them for the next section. If you had rebar going horizontal from one pour to the next is a start. You could also put a keyway in the joint face to further lock the joint. One more step would be a bentonite waterstop between pours would help leakage. Put rebar in your footings that extend through just like the wall. Dowl in some verticals in the footing into the wall. There is always a way.

That's the kind of thing I'm investigating. From what I've read, multiple pours are ok even in commercial work but you have to have a certain rebar between the sections, etc. But it's pretty big risk IMO.

I think pouring the footer by hand would be pretty feasible because the cosmetic requirements are low, forms are simple, and the volume is low. Then I can take my time laying block.

 

[rsanter]

Is it really a savings verses bringing a truck in and doing the labor your.

 

[Rusted Nut]

I just retired from a career in commercial construction. We do multiple pours a lot; but the work is designed, engineered, and planned for multiple pours. If you have the correct rebar, the other main issue is water intrusion at the cold joints. If you think you can pour this by yourself with bags, just get a truck and pour it yourself; you will get a much better product with a lot less work.

 

[Firebrick43]

ICF walls are usually pumped in 4' lifts at at time on a typical sized house. Then the wall is vibrated. If you do to much the hydraulic pressure at the bottom of the wall is too great and can cause blowouts of the wall. By the time you make it back to the beginning the mix should be stiffening enough to lessen the hydraulic pressure issue but not far enough in the hydration reaction to cause a cold joint.

We did 8'5 feet total. The dealer provided assistance on the pour day said he wont go over 12' in a single day as the risk for blowouts is too great. Then you have to plan for the cold joint with rebar and possible other things like bond beams if there is no floor diaphragm there.

 

[OneEyedMan]

Maybe I missed what your projected concrete needs were as far as yards. Several years ago we needed about ten yards worth of 4’ tall stem wall poured. Easy access for a crew and we didn’t want to take time to set up our forms. Found a kid advertising on FB, just bought his own forms and hung out his shingle.

He was at $450 per yard all in and he did a great job. Called him later for another smaller job, he had a 5yd min and was really busy so we did that one ourselves. I don’t know if that’s an option for you but might be worth a look.

In any case, minimize cold joints. Some concrete supply houses rent forms and brackets, I know here you can get as little cement as you need but will pay a five yd minimum.

 

[larry4406]

It's a footer and stem wall for a crawlspace foundation. I could pour the footer and use blocks for the stem wall.

The smart thing to do is hire it out. But with the trades in my town being what they are, nobody has any time for small projects. Once company find out what I'm trying to do, they don't even answer the phone.

How big of an extension are you talking about?

When I did our kitchen extension, I decided to go with a conditioned crawl space using CMU (block foundation). I wanted poured concrete, but it was too small of a job for the concrete guys but was a big enough job for a mason for sidework over weekends.

Our addition is 16x8' with a ~30" tall conditioned crawl space.

• Poured a 24x8" spread footing as its partly in the original overdig for the poured concrete full height foundation. This reduces the applied pressure to the soil. House build was 1987 while the kitchen extension was about 3 years ago (~2022).
• Spread footing was doweled and rebar reinforced to the house foundation wall.
• CMU block was laid and rebar was epoxy anchored into the house wall at the various courses of block.
• CMU cells were later filled - you could elect to do this to save some $$$
• CMU was fully parged and then hot spray tar waterproofed along with draintile, footer weepholes, and a sump crock with pump.
• Interior concrete slab poured with vapor barrier
• Framed and later fully insulated and heated

Not shown is the perimeter and interior drains, backfill, slab prep, slab pour.

 

[billconner]

It's a footer and stem wall for a crawlspace foundation. I could pour the footer and use blocks for the stem wall.

The smart thing to do is hire it out. But with the trades in my town being what they are, nobody has any time for small projects. Once company find out what I'm trying to do, they don't even answer the phone.

I find bagged mix per volume is a little more expensive than ready mix around here, but buying sand and gravel by the yard and bags of Portland cement is about half. Not much more work than bagged mix.

I'd go for the footer - ready mix if volume is greater than minimum order or sand and gravel and cement if smaller. I'd also look at just digging a trench rather than build forms. And definitely lay block. Easy diy. I did a 28x32, one corner 8 courses, dry laid and surface bonded. Wonderful system working alone. Cost of Henry's Foundation Cost. Core fill every 4' with a PC of rebar.

Current addition project is frost protected shallow foundation and looking at systems that allow a single pour. I will hire someone to do pour and finish - just too much solo - including it has to be buggied to back yard. (No one likes to pump here.)

 

[theoldwizard1]

If you have the correct rebar (etc) , the other main issue is water intrusion at the cold joints.

HUGE ISSUE !

 

[NUTTSGT]

I would ready-mix the footer lay the block and core fill the block as needed.

 

[pcmeiners]

Is it ok to do that as long as you have rebar to tie the sections together?

Rebar to tie in is only one issue. I was a foreman and we poured foundations for multi story buildings with cold joints but required forms at the joint, with formed indents and embedded rubber seals, time consuming (rarely done)...avoid this like the plaque .

 

[no704]

Get a mud mixer?

 

[billconner]

HUGE ISSUE !

Does it matter with a stem walk below grade?

 

[billconner]

Get a mud mixer?

I agree but probably more it much more than the cost of ready mix.

Does a Mud Mixer do ok if you're mixing your own aggregate and cement?

 

[75gmck25]

We had a similar project for a porch add-on. We excavated, verified with the city that the footers were excavated to the right depth (1st inspection), and set in the rebar and forms for the footer. I then ordered a concrete truck that had the capability to deliver various mixes on-site based on whatever psi you needed.

However, the truck was too heavy to get it close enough to use the chute directly into the excavation, so 3 of us used wheelbarrows to move all the concrete over from the street to the excavation. Not a really easy task, since we had to build a ramp down into the excavation and run the wheelbarrows up and down the ramp. Footer/porch was only about 20 feet long and 8 feet deep, so it was not really that big of a pour.

We cemented vertical rebar into the footer, spaced based on the architects specs, and also installed "ladders" between about every two CMU courses. All the CMUs with vertical rebar were filled with cement. The first few courses were full depth CMUs, and then we transitioned at about ground level to smaller depth CMUs so there would be a ledge for the brick facing. We also drilled into the house foundation wall and epoxied rebar that tied the footer and CMUs into the existing basement wall. At the top course we cemented in threaded ties for the plate on top.

If you have an architect he/she should give you a plan that shows all the details you need for the footer size and block wall construction.

I chose to not pour a concrete floor We lined the crawl space floor with a heavy vapor barrier, then thick layer of stone, and then rigid foam insulation with all seams taped. On top of it all we laid in interlocking plywood to create a floor.

 

[NUTTSGT]

I agree but probably more it much more than the cost of ready mix.

Does a Mud Mixer do ok if you're mixing your own aggregate and cement?

Not sure Bill but after watching a few videos, I would make the SWAG that you would have to mix dry ingredients together prior to loading in the Mud Mixer.

 

[mike93lx]

Not sure Bill but after watching a few videos, I would make the SWAG that you would have to mix dry ingredients together prior to loading in the Mud Mixer.

I know this doesn't mean it won't work, but the manufacturer calls for bagged. I wouldn't expect it to mix separate ingredients well at all

 

[NUTTSGT]

I know this doesn't mean it won't work, but the manufacturer calls for bagged. I wouldn't expect it to mix separate ingredients well at all

About exactly what I would expect their website to say... However, I never thought about other bagged pre-mixed products.

 

[billconner]

So have to stick with my second hand harbor freight mixer to mix my own I guess.

 

[dscheidt]

So have to stick with my second hand harbor freight mixer to mix my own I guess.

In one of the threads where the mudmixer came up, someone said they mixed their own bulk ingredients in a barrel mixer before feeding it into the mudmixer.

 

[billconner]

In one of the threads where the mudmixer came up, someone said they mixed their own bulk ingredients in a barrel mixer before feeding it into the mudmixer.

Buy two mixers and load two mixers. I'm just not feeling it. Makes ready mix more attractive - albeit IF you can get the truck to the work. I'm struggling with that on a potential project. Would have to buggy from street to backyard.

 

[mike93lx]

Buy two mixers and load two mixers. I'm just not feeling it. Makes ready mix more attractive - albeit IF you can get the truck to the work. I'm struggling with that on a potential project. Would have to buggy from street to backyard.

Hire it out. The crew that did my pool deck did it with wheel barrows. I assumed they would pump or buddy it, but apparently they can get labor cheap enough around here.

the guy running the crew mentioned that he had a pumper tube blow out over a house once... Can't imagine what that was like

 

[duneslider]

I think the footing and block is the way to go if you are wanting to diy this thing. Block really does go pretty quick once you get going on it. Making and reinforcing your own foundation forms is a lot of work and cost too. Block and mason mix is pretty affordable it seems if you are willing to put the labor in.

 

[larry4406]

Hire it out. The crew that did my pool deck did it with wheel barrows. I assumed they would pump or buddy it, but apparently they can get labor cheap enough around here.

the guy running the crew mentioned that he had a pumper tube blow out over a house once... Can't imagine what that was like

Our kitchen extension we used wheel barrows for the footing using ready mix...

 

[dscheidt]

Hire it out. The crew that did my pool deck did it with wheel barrows. I assumed they would pump or buddy it, but apparently they can get labor cheap enough around here.

There’s a break even point, where the cost of setting up and cleaning the pump is more than the time saved by using it. There are also scheduling problems, assuming they don’t own their own pump. Plenty of work is done with wheelbarrows instead of a pump because the job needs to get done, and a pump is not available.

I see the same thing with jobs that are less than a truck. There are times when you simply can’t get a short load delivered, so it’s either wait or site mix.

the guy running the crew mentioned that he had a pumper tube blow out over a house once... Can't imagine what that was like

expensive to clean up, i bet.

 

[Whitworth]

That's the kind of thing I'm investigating. From what I've read, multiple pours are ok even in commercial work but you have to have a certain rebar between the sections, etc. But it's pretty big risk IMO.

I think pouring the footer by hand would be pretty feasible because the cosmetic requirements are low, forms are simple, and the volume is low. Then I can take my time laying block.

San Simeon (Hearst mansion) was made with multiple concrete pours mixed by hand over several months.
The raw materials were brought up from the valley on the backs of burrows.

 

[billconner]

I see a number of contractors around here use an excavator or skid steer to move the concrete from truck on the street to site. One has a bucket with a tube and gate under it. Looked home made.

 

[NUTTSGT]

I see a number of contractors around here use an excavator or skid steer to move the concrete from truck on the street to site. One has a bucket with a tube and gate under it. Looked home made.

You can buy those Bill... Andrew Camarata use has a video where he bought one to help a contractor do a pour. It was a couple of years ago but should be easy to find on YouTube.

EDIT: I stand corrected, that was a skid steer bucket mixer attachment. Sorry been a few years, I thought he had a video for an attachment like you mentioned.


Pump would be handy but still costs in rental and/or labor. If you are DIYing a $1K pump rental fee can go along way towards several yards of concrete. If you are just writing the check for the job, the pump rental fee is getting passed on to you by the contractor.