I need advice on making a concrete pad

[blackrams]

What I would do... is dig down a foot... put down a geotextile.. backfill say 8-12 inches of 0-1/2" gravel and compact it ( it is better to go small layers at a time and compact, making sure the gravel is humid), once it is back filled, then dig the sides out abit so that the concrete is thicker on the edges and also makes a sort of "teeth" to hold the gravel cushion.
Then add rebar... being a patio I would go about 16 inch on center with 1/2inch rebar.. with the perimeter in said rebar too. I am not a big fan of the chicken mesh style of rebar...

And then I would pour a minimum of 6 inches of concrete on center. (The edges should be 8-10 inches thick in this scenario).

Most people will probably say it's overkill on the thickness and rebar, but I personally rather build it once, with a good and thick concrete than to build it too thin and having to redo it five or ten years later...

Using this method you should be fine from frost and weeds...

Hope this helps..

My goodness, he's building a patio, not a place for heavy equipment to operate on. Way overkill. Way more money invested than necessary. Admittedly, I don't know the area but, I have to ask, does the ground heave that much to need that much steel and concrete?

OK, having said all that. Down here in Central KY, I'd ensure the area is level. Since I don't know what the elevation of this patio is supposed to be compared to the surrounding area (such as attaching sidewalks, steps or sloping ground) but determine what the height or level should be and then work from there. Once you know that, you can decide whether to dig down or build up the substrate to get where you need the surface or top to be. For a patio (not heavy weight bearing) I'd suggest a 4" slab. If you have to dig down, ensure you compact the surface below the intended concrete. If you have voids, use appropriate fill such a 1/2" gravel. If you have to build up to get the level you want, use the same gravel fill and compact. Doesn't hurt to have that surrounding foundation but, it's not really necessary unless you do have significant ground heave due to freezing and thawing. I see no reason for all that rebar unless you plan to use this pad for significant weight and of course if you have a lot of that ground heave previously discussed. Personally, I'd use concrete mesh panels, cut to fit. Use 2X4s as your outside forms. Secure, level and stake these more than you think is necessary. Ensure you have the level or slope you want with these forms before you go any farther. I assure you, if not secured well, you'll have a mess to clean up once you start pouring that concrete. I'd use a 3K PSI mix, no need to go heavier for a patio. Where you go from here depends on the type of finish you want on the concrete. Some folks want a broom or swept finish, some want a slick finish, some want a washed gravel finish. Your decision. Regardless, have plenty of help for this pour. Lastly, consider whether or not you need to put joints in to allow for that ground heave to give the concrete a preplanned crack. Guaranteed that half the folks you ask to help you pour this pad won't show up and if you don't have enough help to level and finish this pad, you'll end up with something you'll wish you never started. Been there, done that.

Edited: I always have some other little project for the extra concrete that always seems to be left over. Might think about what that might be.

Rams :drink:

 

[Looking4new]

You would think our wives would be on to us by now. :thumbsup:

No wife.

 

[Turbys_1700]

When do you plan on pouring? I would expect weather and cold conditions in Ontario would preclude this as a winter time project?

 

[Looking4new]

Two of us will be doing the mix/pour.
I am thinking 2x8 forms staked every foot, that should be enough support for the forms. Down the center (I may need to rethink that and make 3 pressure cracks instead of the one) from front to back a 1/4" piece of plywood to create the 'crack'. A 1 degree slope from back to front. I will hand trowel the finished product and 'do' the edges as well. The 2x8s will be more than enough to hold my weight as well as the weight of the concrete.

The plan is to come up about 2" above grade as at a later date I will be making concrete sidewalks as well.

I did a floor in an old pony barn, the floor had a huge crack across it. 4 bags of mortar mix for into the crack (mixed sloppy) and then after that kicked I cleaned the old floor with TSP. I put a new slope in the floor and it all went to a new flush mounted drain made out of a 3"pvc clean out T, with a plug on the inside end to keep vermin out. I kept chickens in there for 10 years and now it is for storage and the crack hasn't come back. So I must have done something right or it was dumb luck.

 

[Looking4new]

When do you plan on pouring? I would expect weather and cold conditions in Ontario would preclude this as a winter time project?

I am looking at May for the pour. I can dig and frame anytime after the snow is gone.
We can expect our last frost to be in June at the very latest, but the fresh concrete can be covered by a tarp to keep the frost off it.

 

[Deere Dude]

My goodness, he's building a patio, not a place for heavy equipment to operate on. Way overkill. Way more money invested than necessary. Admittedly, I don't know the area but, I have to ask, does the ground heave that much to need that much steel and concrete?

OK, having said all that. Down here in Central KY, I'd ensure the area is level. Since I don't know what the elevation of this patio is supposed to be compared to the surrounding area (such as attaching sidewalks, steps or sloping ground) but determine what the height or level should be and then work from there. Once you know that, you can decide whether to dig down or build up the substrate to get where you need the surface or top to be. For a patio (not heavy weight bearing) I'd suggest a 4" slab. If you have to dig down, ensure you compact the surface below the intended concrete. If you have voids, use appropriate fill such a 1/2" gravel. If you have to build up to get the level you want, use the same gravel fill and compact. Doesn't hurt to have that surrounding foundation but, it's not really necessary unless you do have significant ground heave due to freezing and thawing. I see no reason for all that rebar unless you plan to use this pad for significant weight and of course if you have a lot of that ground heave previously discussed. Personally, I'd use concrete mesh panels, cut to fit. Use 2X4s as your outside forms. Secure, level and stake these more than you think is necessary. Ensure you have the level or slope you want with these forms before you go any farther. I assure you, if not secured well, you'll have a mess to clean up once you start pouring that concrete. I'd use a 3K PSI mix, no need to go heavier for a patio. Where you go from here depends on the type of finish you want on the concrete. Some folks want a broom or swept finish, some want a slick finish, some want a washed gravel finish. Your decision. Regardless, have plenty of help for this pour. Lastly, consider whether or not you need to put joints in to allow for that ground heave to give the concrete a preplanned crack. Guaranteed that half the folks you ask to help you pour this pad won't show up and if you don't have enough help to level and finish this pad, you'll end up with something you'll wish you never started. Been there, done that.

Edited: I always have some other little project for the extra concrete that always seems to be left over. Might think about what that might be.

Rams :drink:

X2.

It's a little pad so I wouldn't get carried away with the digging down a foot or two and packing with gravel. Just dig down enough to get the slab flat and pitched correctly and put 2x4 forms up and either a couple 4'x16' cattle panels or rolled concrete wire mesh with 4 or 5" squares. I would just go to a Tractor Supply or equivalent for those. You should be able to remember to pull that up into the concrete on a small slab like that. (But rebar is always good)

If it butts up to another sidewalk or something that moves I would tie them together with rebar because it will move up and down an inch or so from the frost. Don't tie it in to a stationary wall or something that is not movable like a house wall.
I would either ready mix it or at least get a harbor freight stand alone cement mixer for the job. You will need at least one other knowledgeable person to help mix and to get everything screeded and finished off.

That is only 1.25 yards in US so not much. Ready Mix will be easier but the minimum trip charge will make it very expensive. Then like Ram said, if someone who is not very very reliable comes before the truck comes, you are really on your own. It was my very first slab or approx 20' x 30' attached garage floor, had everything staked out nice and had two friends lined up. Truck comes and no help. Luckily they did show up when the truck was backing in so it worked out or I would have been totally screwed. Just get a mixer and a friend for this.

I poured multiple slabs, garages, pole sheds, basement floors and 100s of feet of sidewalks in Wisconsin and did it that way. Never any cracks to speak of. Ready Mix for big stuff and myself and wifey with a mixer for the smaller stuff. I can definitely understand all the precautions putting in lots of gravel and rebar criss-crossed and footings etc. in concrete but I wouldn't mess with in on a small slab like that. The way I do it is not in an industrial setting standards and is just used for foot, car or camper traffic but never had cracking problems in over 40 years. The finish on my slabs are never like the pros but it looks nice and respectable.

 

[check]

Two of us will be doing the mix/pour. I am thinking 2x8 forms staked every foot, that should be enough support for the forms. Down the center (I may need to rethink that and make 3 pressure cracks instead of the one) from front to back a 1/4" piece of plywood to create the 'crack'. A 1 degree slope from back to front. I will hand trowel the finished product and 'do' the edges as well. The 2x8s will be more than enough to hold my weight as well as the weight of the concrete. The plan is to come up about 2" above grade as at a later date I will be making concrete sidewalks as well. I did a floor in an old pony barn, the floor had a huge crack across it. 4 bags of mortar mix for into the crack (mixed sloppy) and then after that kicked I cleaned the old floor with TSP. I put a new slope in the floor and it all went to a new flush mounted drain made out of a 3"pvc clean out T, with a plug on the inside end to keep vermin out. I kept chickens in there for 10 years and now it is for storage and the crack hasn't come back. So I must have done something right or it was dumb luck.

2 x 8 forms is a good idea. Make them pressure-treated, and leave them there. They will form a nice frame for the gravel underneath, and will last for quite few years. Also, I don't know how far off of Highway 11 you are, but if you are halfway between Huntsville and Northbay, the total distance is 129 km, and isn't that road speed limit 100 km per hour? Shouldn't take a concrete truck long to get to you if it only has to travel 1/2 of 129 km at most. The bigger issue would be the surcharge for having such a small load.

Good luck! Been there done that. Used a little electric mixer.

 

[Industrial Toys]

I have a friend building up there. He was telling me the same thing about concrete delivery prices. He bought a nice used mixer from a rental yard. Not consumer junk, and the price was right.

 

[check]

I have a friend building up there. He was telling me the same thing about concrete delivery prices. He bought a nice used mixer from a rental yard. Not consumer junk, and the price was right.

Canadian Tire has them on sale every once in a while. You would need 3 guys: One to get the stuff and mix, and two to place. IF one of you is an experienced concrete person, and you used Sakrete premixed bags, then maybe 2 people could do it.

 

[plowhog]

at least get a harbor freight stand alone cement mixer

I looked at this unit recently. The "teeth" are in the back of the drum with a shaky looking way for a gear to turn it. I bought a Kobalt unit from Lowe's instead. It had the motor mounted to the back of the drum, with no need for gears that could potentially strip out.