Mansonary advice needed

[muddstopper]

Several years ago, I built a small addition to my house. This addition also included extending the basement. my house had rock laid around the bottom and when I extended the basement, I peeled all the rock off, which wasnt easy by the way. I had saved that rock all these years and since the only thing on my new basement that was exposed was where I also added a double door, I just never got around to relaying the rock on the block simply because I didnt know how to mix the mortar. Anyways, A few weeks ago, I got my BIL, who has built several nice looking rock walls around his place, to come up and show me how to lay the rock on my wall. My wife really got into it and ended up laying and grouting the rock and it turned out pretty good in my opinion. I wasnt much help because of recovering from my knee surgery, but I think she did a heck of a job. Well the rock laying bug has bitten the wife and she is wanting to lay a cobblestone patio. She had bought one of those plastic molds a few years back, but never used it. I guess my question now is how do I mix the concrete for pouring those paver stones. I would rather mix the sand and portland than buy the pemix bags because I think it would be a lot cheaper considering the area she wants to pave and I do own a concrete mixer so why buy premix. I also dont want to use gravel in the mix, well to rephrase that, she doesnt want to use gravel in the mix. I figure there are probably several here that have laid their own paverstone patios, so looking for some good advice on the concrete mix ratios they have used.

I kind of hope this paver bug fever dont last to long, she is already talking about that once the patio is done, she wants to redo the firepit we just built by laying a paver patio all around it. My place may soon be covered in concrete.

 

[/pine]

There are many grades (fineness) of sand...(aka "fine aggregate")...generally the more course the stone/rock courser sand is desired...for smoother surfaces like pavers, bricks etc.,etc... regular "play" works well...

For mortar you want mortar mix (and sand)...it has portland cement and lime additives to make it "sticky and buttery"...additional portland can be added for a stronger mix...just sand and portland will make a very strong mortar but it is not very workable or cohesive...
Also it is recommended to use a bonding agent as per the instructions for bonding any previously cured concrete/masonry units etc...usually near the masony products in the box stores...

 

[muddstopper]

Pine, she has bought on of those plastic moulds to make the pavers with. The mix for making the pavers is what I am looking for. After watching youtube, she wants to just pour the mold fight on the ground, which happens to be so hard a back hoe cant hardly scratch it. She figures, just scrape off the grass and lay the mold down and just pour directly into the mold. My concern is getting mix that wont crumble after a few freezes. The whole procedure looks easy enough. Usual concrete mix would be a 1:2:3 mix, portland/sand/stone. but she doesnt want to use stone. For a portland sand mix, i am thinking 2 portland and 3 sand, or 1 portland and 4 sand, but I havent found a mix where you dont use some stone.

I probably should add, the sand I have cheaply available is just screened brown river sand, but could probably hit the rock quarry and get gray rock fines, which would be a lot coarser than the river sand. She will be adding color to the mix so I suspect the color of the sand wouldnt make much difference. If I had to I guess I could also dd some hydrated lime to the mix, I think lime is supposed to make the concrete harder, but aint sure about that

 

[Egon]

Look up the Portland Cement Association site. They have a lot of information.

With your sand I'd suggest mixing a few trail batches and see how they work. Use your normal mix and then add lime to get to the workability you want. Then add more Portland to increase strength.

Commercial pavers will be made with minimum water, pressed and then cured with moisture and heat.

My recomendations come from fifty years ago.

 

[GLyford]

Traditional mix is 3:2:1 Gravel:Sandortland, with barely enough water to get it to mix. Soupy is too far. You want a stiff mix so that it sets up enough to pull the form while you are mixing the next batch, then move the form.

I have done several block patios, one with the "block maker" form and another couple with precast blocks. I used a HF mixer to mix my concrete. I was counting shovel loads using a square shovel, and had my water figured to not quite a gallon. I was doing 4 "molds" per session before work (on 2nd shift at the time), more on the weekends. You can prop the form a little to make up for surface irregularities, you only care that the top is level.

The real problem with this isn't getting the ground level, there are ways to do that. It's not setting and filling the forms, or laying and leveling the blocks. Those are relatively straight forward, if time consuming and labor intensive. Kind of rewarding to see the pation form, though.

No, the real issue is with the cracks. On the forms, they are about 1/2" wide. On the pavers, they are under an 1/8". You can sweep sand over and fill them, then wash it in, and sweep some more, after about 4 or 5 passes the cracks are full. The problem is ants. Ants will dig holes, then drag seeds down into them to feed the colony, and some will sprout. I have to mow my "form" patio. I filled with stone dust, which is worse, since the freshly fractured stone releases a lot of nutrients the weeds love. The paver patio I clear the weeds off with a square shovel every so often.

There is a special sand you can buy that is premixed with resin, called polymeric sand. Shop Sakrete 4-lb Polymeric Sand at Lowes.com
Next paver patio I make, I will use it. But the gaps with the concrete forms are too large to make that an economical proposition, being something like 4 times as wide.

So after something like 2 to 5 years, plan to either mow your patio or keep it saturated with roundup and ant killer.

Since we just put in a pool, I think we will replace our form patio with a slab when they do the pool surround. It will also give me an opportunity to improve the slope (it only slopes in one direction right now), drainage (run the run-off from that side of the garage under) and incorporate changes (we added a back porch and changed the deck).

 

[muddstopper]

Traditional mix is 3:2:1 Gravel:Sandortland, with barely enough water to get it to mix. Soupy is too far. You want a stiff mix so that it sets up enough to pull the form while you are mixing the next batch, then move the form.

I have done several block patios, one with the "block maker" form and another couple with precast blocks. I used a HF mixer to mix my concrete. I was counting shovel loads using a square shovel, and had my water figured to not quite a gallon. I was doing 4 "molds" per session before work (on 2nd shift at the time), more on the weekends. You can prop the form a little to make up for surface irregularities, you only care that the top is level.

The real problem with this isn't getting the ground level, there are ways to do that. It's not setting and filling the forms, or laying and leveling the blocks. Those are relatively straight forward, if time consuming and labor intensive. Kind of rewarding to see the pation form, though.

No, the real issue is with the cracks. On the forms, they are about 1/2" wide. On the pavers, they are under an 1/8". You can sweep sand over and fill them, then wash it in, and sweep some more, after about 4 or 5 passes the cracks are full. The problem is ants. Ants will dig holes, then drag seeds down into them to feed the colony, and some will sprout. I have to mow my "form" patio. I filled with stone dust, which is worse, since the freshly fractured stone releases a lot of nutrients the weeds love. The paver patio I clear the weeds off with a square shovel every so often.

There is a special sand you can buy that is premixed with resin, called polymeric sand. Shop Sakrete 4-lb Polymeric Sand at Lowes.com
Next paver patio I make, I will use it. But the gaps with the concrete forms are too large to make that an economical proposition, being something like 4 times as wide.

So after something like 2 to 5 years, plan to either mow your patio or keep it saturated with roundup and ant killer.

Since we just put in a pool, I think we will replace our form patio with a slab when they do the pool surround. It will also give me an opportunity to improve the slope (it only slopes in one direction right now), drainage (run the run-off from that side of the garage under) and incorporate changes (we added a back porch and changed the deck).

I had sort of figured I would have to keep things roundup'ed. Hadnt considered the ants and I am fighting them already. Wonder if one could premix boron in the sand before filling might help with the ant problem. Just a thought, no clue if it would work, or possible side effects. High boron would help keep weeds at bay also, but might leach out into my grass.

Anyways, your suggested mix includes gravel which my wife wants to leave out. I'm trying to come up with a portland/sand mix that doesnt need gravel, but wont crumble after a few winters. This patio will be laid on prepped ground without any base materials. ground is hard as rock because thats what it is, and only has a thin layer of dirt on it. I already keep it covered with small stone and nothing, including weeds will hardy grow on it. I'll scrape the gravel off before pouring the pavers on the ground.

Another continuation of the paver project is she is thinking about laying the pavers over top of the concrete walk areas already there and the area we park our cars on. The concrete has been there since 1984 and is starting to look pretty weathered. I am not sure how well pavers would hold up to being driven over with a car, even with a concrete slab under the pavers. Her eyes and wants might be overloading her, and mine, backs. at any rate, I dont want to go thru the work of cobble stone'ing my parking area only to have the pavers crumble because of being driven over with a car.

 

[KennyG]

What is the point in omitting the stone? When you finish the top surface you won't see the stone. A mix without stone will be much weaker and you will probably have a serious cracking problem down the road.

 

[muddstopper]

What is the point in omitting the stone? When you finish the top surface you won't see the stone. A mix without stone will be much weaker and you will probably have a serious cracking problem down the road.

I have tried explaining that to the wife. Had the same discussion with a telephone pole with similar results.

 

[KennyG]

I have tried explaining that to the wife. Had the same discussion with a telephone pole with similar results.

:laughing: Been there, done that.

 

[muddstopper]

She is trying to save money, but I havent priced the sand or gravel yet and I doubt using more sand and no rock is going to save anything. One thing I am considering is using rock screening from the quarry instead of gravel. Its coarser grain than sand. I remember growing up, my dad poured the concrete for a carport. We went to an abandoned quarry and shoveled those fines into the truck and thats what he used to make the concrete with. I dont remember what the mix ratio was, pretty sure there wasnt any rock added, but I grew up there and I dont remember the concrete slab ever having a crack in it.

 

[Egon]

Commercial pavers may not use stone.

Mix the two sand sizes to get better density and use more Portland to allow for the gap grading.

 

[GLyford]

Crusher fines are bigger and coarser than sand, and will lock better for more strength. I'd go with crusher fines, with or without sand before I would go with just sand.

On my form pavers, which used 1/2" stone and crusher fines (should have used graduated size gravel and sand), there are places where the water sits and freezes where they are already coming apart. In place still, and still OK for putting patio furniture on, but when the ground is saturated you can feel the pieces move when you walk on them. If you want it to last, straying from the "best practices" mix is not the way to go.

Have you priced out getting a slab poured? Framing one up isn't that hard, and if you don't mind a broom surface not too hard to finish. Hardest part is shoveling the mix around and screeding off. Hire a finisher and even that isn't too bad. And you could use real rebar, or put your wire on chairs if you want. Or not put in any metal at all, as long as you keep remembering it is a patio and not try to park cars on it.

 

[GLyford]

Pavers on top of a slab is the best way to do them, most people don't bother because you are paying for both pavers and a slab. But to dress up an existing slab, I say sure. Top dress and screed with a little sand to bed the pavers in (I would have to look up the recommended depth, but I suspect 1/2" would be fine) and go wild.

 

[muddstopper]

Heres what I am thinking for a mix. 2 portland, 2 sand, 3 rock fines. Anybody think that will hold up and not crumble if laid on top of concrete slab with vehicle parking.

 

[Egon]

With the right amount of Portland cement it'll do just fine.

You don't have to worry about the aggravate locking together. The cement makes the glue that binds it together.

The object is to get the fines and sand mixed to maximum density to reduce void space. This saves cement as it must fill the voids.

 

[muddstopper]

Mixing wont be a problem, I have a mixer

 

[forgeblast]

I did a lot of casting from the forms for borders and for pavers. The main thing I saw or had happen was the form failed after a bit. If its the cheaper plastic forms, tape it in duct tape, and put it on a piece of plywood so that your not using the form to flip the cured paver. You can spray the forms too with spray veggy oil to help with the release. If its on plywood too you can hit the plywood to get the air bubbles out of the surface.

 

[DaveK OR]

To keep the weeds from growing up, add a good pre-emergent herbicide to your spray mix. Be careful with which you choose, because some of them will stain stain concrete.

Roundup has an off-the-shelf mix that includes a pretty good pre-emergent, and with that it should stay weed-free for 3-4 months at a time.

Another alternative is to sweep some Casseron or similar soil sterilant into the cracks and spaces between pavers.