Author Topic: Pouring a concrete pad  (Read 3904 times)

Mattzlaff

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Pouring a concrete pad
« on: April 05, 2016, 04:23:15 AM »
So I'm pouring a concrete pad this summer. I have read a few DIY wikis and it doesn't seem tooooo complicated. I have a buddy at work that doesn't know it yet but he's helping me, he did concrete work for 11 years before this job so I bet he's pretty handy at it.

Basically, Something like a 12'x12'ish pad either 4 or 6" deep No stamping or anything to maintain continuity between existing driveway pad and new.

Has anyone else done this, what results or things would you share? Helpful tools?

Mix concrete myself or hire out the truck? It's approximately 1.4 meters cubed(Canada eh) for a 4" deep pad or just over 2 for 6" sounds like concrete is 200-250$ per meter cubed where I live.

How do you go about creating a reliable slope away from the house?

What material worked well for expansion join between the old pad/house and the new pad

Should I make the forms and hire out for the concrete and the finishing or DIY it all the way? Ive never done this stuff but my pal may know a lot more than me.

That's all I can really think of this morning I'll check back later after I wake up!


J Boogie

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Re: Pouring a concrete pad
« Reply #1 on: April 05, 2016, 07:17:37 AM »
I don't know much about concrete but I know enough to say with confidence that you should absolutely get a truck.  Once you take into account all the bags you'd have to buy and plan for your mixing container(s), it will be pretty clear the truck is the way to go.

lthenderson

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Re: Pouring a concrete pad
« Reply #2 on: April 05, 2016, 07:27:02 AM »
So I'm pouring a concrete pad this summer. I have read a few DIY wikis and it doesn't seem tooooo complicated. I have a buddy at work that doesn't know it yet but he's helping me, he did concrete work for 11 years before this job so I bet he's pretty handy at it.

Basically, Something like a 12'x12'ish pad either 4 or 6" deep No stamping or anything to maintain continuity between existing driveway pad and new.

Has anyone else done this, what results or things would you share? Helpful tools?

Mix concrete myself or hire out the truck? It's approximately 1.4 meters cubed(Canada eh) for a 4" deep pad or just over 2 for 6" sounds like concrete is 200-250$ per meter cubed where I live.

How do you go about creating a reliable slope away from the house?

What material worked well for expansion join between the old pad/house and the new pad

Should I make the forms and hire out for the concrete and the finishing or DIY it all the way? Ive never done this stuff but my pal may know a lot more than me.

That's all I can really think of this morning I'll check back later after I wake up!

I've poured lots of concrete over the years so here are my answers:

The biggest mistakes I've seen people do is pour the concrete too wet which weakens it, (drier is better) and not tap the forms to remove air bubbles so when the forms come off, the concrete looks like swiss cheese on the edges. It requires a minimum amount of tools and is easily a DIY project. You need an handheld aluminum float and I recommend an edging tool to round over the outside edges to minimize chipping over time. Assuming it is a open slab, I would just rent a large float from the concrete company that delivers the mix for the pour. It is generally a nominal fee and much cheaper than buying.

I would suggest having it delivered instead of mixing it yourself for a novice. That way you don't end up with piles of sand, gravel, cement left over or even worse, not enough. It also takes a lot more effort and time to pour a pad when you are mixing it up as you go.

It doesn't take much slope to drain concrete away from a house. I'm not sure what the recommended amount it but I would do at least one inch every ten feet, possible every five depending on rain amounts and intensity in your area. A simple level is what I use but you can also use water in clear plastic tubing to create your own level.

For expansion joints, I generally use closed cell foam that you can buy in a roll at most big box hardware stores. It comes about six inches wide and is about a 1/2 thick and comes in a roll.

I would definitely make your own forms. For a four inch pad, by 2 x 6 material and for a six inch pad buy 2 x 8 material. I usually use 2 x 4's with pointed ends to pound in for stakes to hold the forms in place. Make sure you put your fasteners holding the forms to the stakes from the stake side and not what will be the inside of the form. Make sure the stakes are below the level of the form so you can use a straight board as a screed when you are pouring the concrete.

As I do with all projects like this, check out Youtube because there is a wealth of information in video form on just about any DIY project you can think. It will give you a good idea of what is involved and various ways to tackle the same project.

Arktinkerer

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Re: Pouring a concrete pad
« Reply #3 on: April 05, 2016, 09:08:41 AM »
Concrete is heavy and doing a pour is hard work.  Not complex but hard physical labor to do well.  Having multiple people to do the job is highly recommended.  Buy vinegar to wash off with after finishing--concrete is a caustic base and will eat your skin.  Get it in your boots and the abrasive and caustic material will make painful sores.

Second on the truck and make sure you buy a bit extra because being short is definitely a big problem.  Have some small forms to cast blocks to use the excess.

Le Poisson

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Re: Pouring a concrete pad
« Reply #4 on: April 05, 2016, 12:20:09 PM »
You already have great info. the only thing I'll add is that the drainage spec on sidewalk contracts is 2% slope. Installers refer to this as "Quarter Bubble" as in:

Afonso: "You want quarter bubble slope chief?"
Davi : Yeah, that's what they said, but maybe we can do third of a bubble if we hafta."

Measured, it looks like this:



One quarter of the bubble on the level will be past the line, rising toward the house. This means water will drain away from the foundation. The sidewalk/patio will still feel level when you sit on it, but the slope will be adequate.

Goldielocks

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Re: Pouring a concrete pad
« Reply #5 on: April 08, 2016, 05:41:20 PM »
I am a novice, too, but making our own forms and tieing all the wire/ rebar in was easy. We hired out the pour.   Final finish exposed aggregate.

Notes. The wash off killed a large decorative shrub about 8 ft away.  ( wash water ponded)

We tied 2x the rate minimum recommended as our labour was free and it is a driveway. I would do that again.

Metric Mouse

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Re: Pouring a concrete pad
« Reply #6 on: April 09, 2016, 05:38:29 AM »
How do you go about creating a reliable slope away from the house?

For the slope, you slope the ground before you build the forms on it. I would use a string level and some stakes to make sure my grade was even and I wasn't sloped along a different axis. The grades mentioned above are probably pretty good guides.

Fishindude

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Re: Pouring a concrete pad
« Reply #7 on: December 21, 2018, 10:57:09 AM »
The trick to a good slab is a good base underneath it.   Think of a concrete slab like a piece of glass.   Lay that piece of glass down on your smooth, solid kitchen floor and you can stand on it without it breaking.   Lay that same piece of glass over soft carpet, stand on it and it will break into pieces.

Strip the sod or any organic material from the area, excavate to allow for 4" - 6" of crushed stone under the slab, neatly grade and level the stone, thoroughly compact the crushed stone using a vibratory plate compactor multiple passes, adding and regrading as you go to get a nice uniform surface to pour on.   If the base is solid, your slab will hold up well.

I would put some wire mesh reinforcement in the slab also.   I'm not a fan of the Fibermesh they mix into the concrete for reinforcement.

And lastly, buy your concrete from a local redi-mix plant rather than trying to mix it yourself.