Are you planning for curb line landscape? Or maybe you’re planning on doing the border curb yourself?
A concrete border curb can be a good-looking way to decorate your yard as you can play around with the concrete color and imprint patterns on it easily. There are two things that might put you off from doing it.
First would be can you do it. Second would be the curing process.
We’re not going to go over those so I’ll be writing more about the concrete and how long it takes for the self poured curbing to cure.
How long before concrete dries
So how long does it take for concrete to settle? It will be touch dry in 24 hours. It can be even stand upon but depending on the weather and how cold and damp it is, it might take longer to cure on the ground.
The curing temperature should be over 50 °F and under 90 °F. Now it always can’t be as we know weather can be hot in the summer, but for those kinds of conditions, there are other solutions. There is about hot weather concreting in the link.
Cold weather, as stated before, can also affect the curing process. Here is a guide on cold weather concreting for those interested. For this guide, I’ll just say let us work when it’s over 50 °F.
If the wet curb mix concrete freezes, it won’t be any good. Imagine water expanding as it freezes and is yet to react with the cement. It will harm the overall strength.
We can argue that does it matter on the curbing, but I like to do it the best I can. For that reason, I’d also water the concrete curbs for the first days, at least three. Concrete slabs are watered for a week or more.
The concrete curbs will be good after a few days, for being completely cured it will take 4 weeks like it does with concrete slabs.
concrete curb forms
Curb forms should be given a coat of concrete form oil for easy removal. These can be removed the next day to get them off easily.
How long does concrete cure doesn’t matter here as you will be leaving them to cure. You just want to take the easy route in removing these as they can stick hard when the concrete cures. It’s ideal to remove them when the concrete isn’t too hard so you don’t have to use too much force.
Overnight has worked for me so far when I’m making small forms.
Does concrete ever fully cure
Does concrete ever stop curing? This question I’ve seen many times and the truth is, it doesn’t. For practical purposes, we like to speak of the first 4 weeks as the most gains in strength are made there.
To gain a better understanding of the concrete strength gain and how long it takes for cement to set up with water, in 7 days it has ¾ of its 28 days strength. The last ¼ happens in the next three weeks.
So the curing and gains that happen after that are minimal and happens very very slowly. It’s also something that happens with different materials. The early strength is gained like that and the later curing is another reaction that happens slowly.
The main parts that contribute to strength are calcium silicates and water. Tricalcium silicate is the reason for early strength while dicalcium silicate is the reason for later strength.
How long until concrete can get wet
Water is good for the curing process, but how fast can you water the concrete, or how long you have to protect it from rain? Most of the time our main concern, when we are building under an open heaven, is that will it pour rain.
Concrete shouldn’t get wet at its wet form straight after it is poured. It will cause problem with the water to cement ratio on the surface, making it weaker.
What it causes is the surface might turn to dust later, flake or start scaling. None of that is wanted on decorative concrete or our slabs.
So how long until concrete can get wet? About 4-8 hours. I’d personally do the pouring of curbs on a day when it doesn’t rain or at a place where it doesn’t rain into.
Both depend on the type of curbing as well. No one wants to be transporting big pieces of concrete curbing so the big pours should be done at the place where they will be placed.
The forms should be built there at the spot. I’m writing this as it might seem like a good idea to do them in a different location, but the concrete weight adds up really fast and soon it’s not something a single person wants to be carrying.
How to clean concrete curbing
I included cleaning of concrete curbing in this post as it’s really relevant if you want to do decorations. Concrete curbing colors can be done beautifully and imprints as well so it would be a shame if it’s ruined too fast.
I’m saying this as most of us homeowners have pressure washers for our driveways and other surfaces. Fresh concrete shouldn’t be pressure washed before the 28 days are over as it can damage the surface.
High-pressure washers can easily damage old concrete surfaces so it’s no wonder they can do that to the new ones. Also, when you pressure wash the new concrete, it will penetrate deep into the concrete structure potentially harming the curing process.
So how do you clean your new curbing if that isn’t possible? We use softer methods like hot water that is poured on the concrete and brush. That won’t harm the surface.
I have guides for different stains here like rust and tar. Then there is also guides for other stains like mold and moss.
There is also option of using muriatic acid, but if there is decorative surface I’d not do that.
Most of the time our curb stains are caused by nature like leaves, soil, and cut grass. For that reason, as the concrete surface is porous, I’d use a sealer for the decorative curbing so it will be easier to clean.
We got a little bit off from how long does it take for concrete curbing to cure, but these are things that are close to the subject. If you plan on doing it at home, it will be a couple of days for early strength, a week for ¾ strength, and 4 weeks for what we think is the maximum.
It’s good to protect it from the rain for the first day at least. I’d place plastic over the forms so that it won’t cause marks on the finish. For decorative concrete, this is more important than for regular grey.
After the forms are off, I’d avoid cleaning the curbs too heavy-handedly during the first month. The sealer can be used after 28 days are up so until that you want to avoid unnecessary stains.
I know it’s hard to avoid when you take care of your lawn, but it’s good to try. After you have sealed the surface of the curbing, you don’t have to mind them that much from then on.
The only thing you might want to consider is using sealer regularly so it can keep on giving protection for the curbing. Depending on your yard, you can make it a regular habit for the rest of the concrete surfaces as well.
If you’re interested to know more about curbing and curb appeal, read from the link.