I am building a small deck at the cabin and have bought pre-made footings 50cm high. I got the tip to pour a few liters of concrete at the bottom instead of putting a garden slab at the bottom and fussing to get it level. The idea is to pour about 5 liters of concrete at the bottom of the hole, place the footing, make sure it's level, and then fill the hole with what was dug up. How long should I wait for the concrete to cure before loading the footing with the rest of the deck construction? Is it a bad idea to fill the hole immediately, does it cure poorly then? Does the whole plan sound like a good idea or is it crazy?
The idea is great, simpler and faster, and provides a larger base to withstand the pressure from above.
It is a very good idea.
Just as pointed out, you get a slab that distributes the pressure.
Another advantage compared to a garden slab is that you don't have to be as meticulous about achieving an even excavation bottom. Wet concrete is kind of self-forming in that way.
Just as pointed out, you get a slab that distributes the pressure.
Another advantage compared to a garden slab is that you don't have to be as meticulous about achieving an even excavation bottom. Wet concrete is kind of self-forming in that way.
That sounds like a great idea. I (who don't know a thing about this) see two potential pitfalls besides it possibly not burning as it should if you fill it up directly. Will the "cake" stick permanently in the footing, and can the cake manage without reinforcement?
If these concerns are unfounded, this is probably a method I will use as soon as the opportunity arises
...or is this how the pros do it?
Sent from my ST17i using Byggahus
If these concerns are unfounded, this is probably a method I will use as soon as the opportunity arises
...or is this how the pros do it?
Sent from my ST17i using Byggahus
Concrete cures just as well covered as uncovered in your case. Mix it fairly stiff so that it offers some resistance in the hole when you set the plinth. Slightly less water than what it says on the bag. You can advantageously extend the concrete with some macadam or gravel - clean ones - you don't want to mix in a lot of soil with the concrete.
You can advantageously moisten the plinth slightly before you drive it into the hole and embed it thoroughly in the concrete to achieve good adhesion.
After a couple of days, at "normal" temperatures, you have about half the final strength. After a week maybe two-thirds, and after a month, it has almost completely cured.
You can advantageously moisten the plinth slightly before you drive it into the hole and embed it thoroughly in the concrete to achieve good adhesion.
After a couple of days, at "normal" temperatures, you have about half the final strength. After a week maybe two-thirds, and after a month, it has almost completely cured.
Oh shit... Encountered water about 50cm down... (was planning to use 50cm footings...) What do I do now? I guess I can forget about pouring concrete in the hole, it will probably never set if it's essentially on/in water? Should I dig a little deeper and put about a decimeter of crushed stone at the bottom to try to drain it? Better to place a garden slab at the bottom on top of the crushed stone?