Concrete additives for crawlspace scratch coat/rat slab reinforcing
AJ__
| Posted in General Questions on
I’m considering using a fibre additive instead of wire mesh for reinforcing my ~2″ crawlspace scratch coat/rat slab for logistical and practical site reasons at this time.
Does anyone have any product recommendations or points of note for the process itself when using these additives? Concrete is mixed as it’s dispensed from the truck.
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Replies
Alex,
Scratch coats are rarely reinforced. The idea being you are just providing a very thin cover for the soil and vapour barrier below. If you want to increase the strength, the easiest way is to make the slab thicker.
Thanks Malcolm, construction friend of mine was adamant they were reinforced even in a crawlspace. Looks like I'll skip it.
I'd concentrate on the substrate. Lots of water, lots of compaction.
What substrate are you referring to?
The fill you have used to built up the level of the crawlspace floor.
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Great, thank you, we crushed a lot of blast rock on site and have some good material to work with
Just order fiber when you place your concrete redi-mix order. Most batch plants have it or can get it. Rat slabs don't really need reinforcing as the small amount of cracking that may happen isn't of consequence since it's not a structural issue
I agree with the others, just order fiber reinforcement in the batch of concrete you order.
If you’re really worried about putting some reinforcing in the slab, remesh isn’t all that expensive. Rat slabs aren usually reinforced though — they’re not really intended to function as a real, load-bearing slab. Rat slabs are just to provide a smooth surface and a basic seal to whatever is underneath.
Bill