Pouring concrete pads?

[marlboro180]

Re: Pouring concrete pads?

The most important thing you will need, other than having it delivered , proper tools and equipment,and extra hands .... is someone onsight with experience in concrete finishing....only experience will tell you when to start the finishing process....(what to do and when ). You might consider hiring a concrete worker just to guide you thru the process....have him check your forms and sight prep the day before. Keeps your eyes open for a concrete contractor at work , and stop and talk with one of the crew...its easy side $ for the crew member, and a good insurance policy for a well done job. Just my 2 cents...


don't forget the beer !

Very good point. Finishing is an artthat I am not very good at, but try anyway. Learned the hard way with my dads slab. He was forgiving though...Had a friend teach me on one of his jobs, I am better now, but the pros are great.

 

[fishrdan]

Re: Pouring concrete pads?

I've seen concrete finished a couple times, but never had my hands in it. I check with my friends and see if anyone knows of someone with experience.

I'm going to keep it covered with plastic for 3 days or so, wetting it every 12 hours.

How long will it take for it to setup so the neighborhood kids won't be able to write in it or mess it up. I'm going to have my work cut out for me on keeping the kids out of it as they are used to "cutting the corner" on their bikes and scooters.

 

[kkirt1]

Re: Pouring concrete pads?

All good info.

Concrete is a pershible product. It will not wait on you. Make sure you have the manpower to place and finish in a timely manner. Depending on the outside temp it may go in an hour (hot weather) or may take several hours before it can be finished. If the top is sealed with a steel trowel before the bleed water has escaped scaling may occur.

If you cover the concrete with plastic it may be discolored. Using a cure-n-seal will accomplish the same thing and will also protect it during curing. Depending on the weather, the concrete should be kid proof in 24 - 48 hours.

I have seen a lot of bad do-it-yourself concrete but I guess that is why we keep busy

 

[fishrdan]

Re: Pouring concrete pads?

Hopefully I'll do a decent job, I'm pretty anal about stuff like this as I want it to turn out looking nice,,, just not hack it out as quickly and easily as possible. I looked at a couple pads that were added in my neighborhood and think I can do as good of a job as was done on those.

I'll check out the cure-n-seal as it sounds better/easier than plastic that might blow away.

I've made the project a bit bigger and it looks like I'm going to need 2.3 yards, plus an extra 1/2 yard so I don't short myself. Still not bad as it looks like the concrete will be under $300. Here's what the lay out, sorry for the small pic.

 

[Bob_VT]

Re: Pouring concrete pads?

Some concrete companies will charge for small loads..... call them and you might find a place for more concrete........

 

[25-06shooter]

Re: Pouring concrete pads?

Cure and seal can be bought at Lowes or Home Depot most of the time, if not, the concrete company can tell you where to get it. Use the water based seal and spray it on with a bean sprayer thick and heavy and roll it in with a thick paint roller on a pole. The oil based seal will actually leave a coating on it similar to polyurathane (sp?).

For exterior work you will want to broom it. If you have ever stepped in the garage with wet feet you will know why. Find the softest push broom you can find, lay the broom on the far side of the new walk, lower the handle as close to the ground as you can and in one slow, smooth motion drag it back to you without stopping. If you wait until it is almost dry it will be a light broom finish. If you aren't happy with the finish just float it out and try again.

This time of year it will take forever for the concrete to dry hard enough to broom. Pick a day that it will be above 50 degrees, place it, screed it off, bull float it, hand float it, and don't touch it again until it is ready to broom. Like some other things, the more you play with it, the wetter it gets.

Make sure that your sub base is not frozen before you pour, and make sure the concrete does not freeze for 7 days after it is poured. Concrete blankets designed for this can be rented at some rental companies. Do not allow vehicles on it for the first week minimum, 2 weeks if you had to keep it covered for the first week. It actually takes 28 days for it to come to its maximum strength, but it should be at 70% by the first 7 days.

I haven't checked, but there may be instructional videos on you-tube. They have everything else on there.


Nate

 

[fishrdan]

Re: Pouring concrete pads?

Thanks for the tip on using a fine brush Nate. I looked closely at my driveway and it was lightly brushed and that's what I'm going to try and duplicate. The other pads that have been installed in my neighborhood over the past few years look like a cheese grater and I don't want that on my driveway.... I don't want my kids getting severe road rash just from falling down in the driveway.

The weather shouldn't be a problem as I'm in the desert and it's been in the mid 60's for the past couple weeks. I think the coldest it's been here all winter it the high 40's

I've been checking out youtube and picked up some knowledge,,, probably just enough to make me dangerous





So what's making me go nuts and rip up the front yard, landscape everything and install a couple of concrete pads???

I live in a tight subdivision and my front door leads out to the neighbors property, kind of a side yard that both our front doors face. For the 12 years I've lived here the neighbors have never done anything with their yard, it's basically been a dirt lot with weeds and cat cr@p, except for the small portion that I have been able to water and keep grass on, but it still looks hideous. Wellllllll, the neighbors house was foreclosed on and they moved out so I'm fixing up the yard the way I want to,,, even though it's not my properly.

You might wonder where my front yard is located, it's on the back of my house facing the other neighbors front door,,, and has been watered with a nice lawn for yeeeears. Nice for them to have a good looking lawn when I was the person maintaining it


Anywho, Once I get done with this in a few weeks I'll be able to walk out my front door and look at a nice yard, river rock or some type of decorative gravel, couple of palm trees, no grass to mow.

 

[roscoe]

Re: Pouring concrete pads?

I'm going to have my work cut out for me on keeping the kids out of it as they are used to "cutting the corner" on their bikes and scooters.

Sounds like a good place to put a raised curb. Maybe with 1/2 nails sticking up out of it.

 

[fishrdan]

Re: Pouring concrete pads?

OK, work is progressing and I'm getting closer to ordering concrete, shooting for Monday to have it delivered.

One question I haven't been able to figure out, how do I screed off to the existing slabs, without making a huge mess all over the existing slabs? Should I tape down a 3' strip of plastic on top of the existing slab so I don't muck it up? The driveway edges have a slight slope to them (1/8" over the last 6") so I'm going to have to use a screed that reaches at least 1' onto the existing slab. Just trying to make sure I don't get fresh concrete mess all over the existing slab.

Oh, another question. What's the difference between asphalt impregnated expansion joint and the plain fiber expansion joint, or when should I use one over the other? I leaning towards plain fiber expansion joint as it's 3" instead of 4" (4" would need trimming) and it's 1/3 the price. It rarely freezes here and doesn't freeze hard, so I'm not sure I need to go with the better one.

Last question, should I, glue (liquid nails?) the expansion joint to the existing slab the day before the concrete is delivered? I'm thinking it would be better to have it stuck to the existing slab so I don't have to monkey around with it while placing the concrete.

Thanks!

 

[rbh]

Re: Pouring concrete pads?

If this slab is going to float independently from the existing slab, dont worry about it as they wont bond very well (sugar water can help). I just poured our extended slab a couple of years back, used rebar due to the fact that it would be driven over by heavy trucks as well as the frost side of the shop.
didnt have a good trowl so I used a 2x4 to float/finnish the concrete.
after it sat for an hour hit up the mess with a hose to wash off the old concrete, "dont hit the fresh unless you want that exposed aggragate look"

 

[fishrdan]

Re: Pouring concrete pads?

The (2) slabs I'm working on will be locked in on 3 sides, so I think I'll need the expansion joint. I imagine those slabs will grow a bit in the summer when it gets 100*+ outside

 

[dockwrecker]

Re: Pouring concrete pads?

COMPACTION!!!! THE most important step for slabs on grade! Rent an elephant's foot or plate compactor, moisten the soil (DON'T make it muddy) and beat the hell out of it until you can no longer detect tracks/displacement in the soil. Slabs on grade shuld be placed on no less than 95% compacted soil typically with a 7% moisture content. Use the 6x6 wire mesh (homeowners should not attempt rebar) and pull it up during placement. A 4000psi air entrained mix is ideal. Your local concrete batch plant will probabaly refer to this as a "city spec sidewalk mx". Pour it and screed boeard it to grade. I would only put the expnsion around the existing slab and tool a joint maybe two while finishing. Your slab ain't that big, but tool joints will get it to crack in the right places when it does. Now bull float it. It will usually start to harden for finishing in about 4 hours at 60 degree temps, you'll feel it start to build heat as it rolls over to hardness. There's no set time here so pay attention! Do your finish trowling. Let it sit until you can just scratch it about an 1/8 inch with your fingernail then broom it lightly. You could be anywhere between 4-8 hours from placement here so allow for a full day and appropriate quantity of beer.
No way would I bag mix 2 1/2 yards and expect any consistency, the little batch trucks/trailers are the way to go.
Good Luck!

 

[j_martin]

Re: Pouring concrete pads?

A quickie, (I'm late for supper)
When I pour a small job, I usually show up at the redi-mix plant with a couple of 55 gallon drums. They'll add what you need to another load, and then dump it into your barrels on their drive.
Takes a couple of gorillish friends to get them tipped over, but saves a lot of money.
It takes a real trailer. They weight about a ton apiece.

hope it helps
john

 

[ThumbPkr]

Re: Pouring concrete pads?

You can place a 2x4 on the same grade as your existing slab but several inches away from it and use it instead of your slab to rest your screed on when placing the concrete.It can be a firring strip or whatever you have available.If you have a trowel handy you can keep the product off of the old concrete as you work.You probably could place polyethylene sheeting over the old walk and anchor it behind the expansion joint and trim it after the concrete is cured if you wanted to.Ron G

 

[25-06shooter]

Re: Pouring concrete pads?

OK, work is progressing and I'm getting closer to ordering concrete, shooting for Monday to have it delivered.

One question I haven't been able to figure out, how do I screed off to the existing slabs, without making a huge mess all over the existing slabs? Should I tape down a 3' strip of plastic on top of the existing slab so I don't muck it up? The driveway edges have a slight slope to them (1/8" over the last 6") so I'm going to have to use a screed that reaches at least 1' onto the existing slab. Just trying to make sure I don't get fresh concrete mess all over the existing slab.

Oh, another question. What's the difference between asphalt impregnated expansion joint and the plain fiber expansion joint, or when should I use one over the other? I leaning towards plain fiber expansion joint as it's 3" instead of 4" (4" would need trimming) and it's 1/3 the price. It rarely freezes here and doesn't freeze hard, so I'm not sure I need to go with the better one.

Last question, should I, glue (liquid nails?) the expansion joint to the existing slab the day before the concrete is delivered? I'm thinking it would be better to have it stuck to the existing slab so I don't have to monkey around with it while placing the concrete.

Thanks!

Asphalt impregnated is better, it will last longer, the other stuff falls apart once it starts getting wet. You can liquid nail the expansion joint to the existing concrete, but I normally use cut nails and nail it on. Either one will work fine. Set the top of the expansion joint 1/4" to 1/2" below the top of the existing slab so you have room to tool the edge and it won't be sticking up when you are done. I would also cover the existing concrete with plastic and let the edge cover the front of the expansion joint and go down under the walk about a foot. Make sure you don't have any wrinkles in the edge or it will show up when you are done. A razor knife will cut it off flush and it will never be seen.

Nate

 

[dockwrecker]

Re: Pouring concrete pads?

Three absolutes about concrete:
It will stick to anything you don't want it to.
It's gonna crack.
No one will ever steal it.

 

[fishrdan]

Re: Pouring concrete pads?

It will stick to anything you don't want it to.

Yeah, that's why I bought a cheap pair of rubber boots instead of using my $60 deck boots. If I use the cheap rubber boots nothing will stick to them, if I use expensive deck boots they will be ruined. That Murphy's law 2.0 or something like that, isn't it?

After digging/leveling/compacting the ground I'm averaging a 4.5" slab. I calculated out that I was going to need 3 yds, but ordered 3.5 just to make sure I wasn't shorting myself.

The question of what to do with the tail end of the load was brought up. This company hauls it off and disposes of it, I guess that's what the $10 environmental fee is for.

 

[Tim Frank]

Re: Pouring concrete pads?

Have a few basic forms prebuilt and use any extra to fill for boat anchors...permanent/mooring type.
If you can't use them, some of your friends might.

 

[fishrdan]

Re: Pouring concrete pads?

Concrete went pretty well today and everything looks good (good enough). The only thing that bit me was the expansion joints. I waited too long and the concrete was starting to set, it was next to impossible to get the groover to shove the aggregate out of the way so it could form the groove. I attempted 1 and made a nice mess and then decided to fill it back in and cut the expansion joint with a saw.

What type of saw/blade can I use to cut the expansion joints? I have 2- 6' and 2-3' 1" deep cuts to make. I have an old circular saw (the kind where I don't care if it gets messed up) and thinking I might buy a blade and go to town. Maybe rent the blade since I'll only use it once? I have a good rental place close by and might give them a call to see if they have any concrete cutting saws, could be cheaper than buying a blade.

Oh yeah, thanks for all the advice you guys shared!

 

[rbh]

Re: Pouring concrete pads?

YES to renting the saw, get the disposable blade, as the other has to be kept wet, and you dont want to pay for one of those expensive metal ones.