Hello!
I need help with how much expanding concrete I need to buy.
I'm planning to cast a countertop and thinking of buying Expanderbetong Weber Exm 702 Fin 20kg (https://www.k-rauta.se/produkt/expanderbetong-weber-exm-702-fin-20kg/7391479734705)
The countertop will be cast in place, not to be turned. L-shaped, a total of about 8 m long, 80 cm wide, and 4.5 cm high.
How many bags might be needed?
Is there someone skilled who can calculate this for me?
I need help with how much expanding concrete I need to buy.
I'm planning to cast a countertop and thinking of buying Expanderbetong Weber Exm 702 Fin 20kg (https://www.k-rauta.se/produkt/expanderbetong-weber-exm-702-fin-20kg/7391479734705)
The countertop will be cast in place, not to be turned. L-shaped, a total of about 8 m long, 80 cm wide, and 4.5 cm high.
How many bags might be needed?
Is there someone skilled who can calculate this for me?
288L will be needed.S Simon89 said:Hi!
I need help with how much expanderbetong I need to buy.
I'm going to cast a countertop, planning to buy Expanderbetong Weber Exm 702 Fin 20kg ([link])
The countertop will be cast in place, not to be turned over. L-angle, total about 8 m long, 80 cm wide, and 4.5 cm high.
How many bags might be needed?
Is there someone skilled who can calculate this for me?
You have received two good answers. The volume is easiest to calculate by multiplying length x width x height in dm to get the number of liters needed to fill the mold. With the information you have provided, it will be 288l. Each bag gives about 12l of ready concrete. It's always a good idea to have an extra bag or two, so based on the given conditions, it might be appropriate to have 2-3 extra bags, so my answer is 27 bags.
I hope you are aware that it won't be an easy cast if you intend to pour everything in one piece. The workability of expander concrete is usually about 30 min. You need to mix, get it into the mold, and thoroughly knock the mold. If you have a good concrete mixer and preferably 3-4 people helping, it will work out well. If you are completely alone, I predict problems.S Simon89 said:Hi!
I need help with how much expander concrete I need to buy.
I am going to cast a countertop, planning to buy Expanderbeton Weber Exm 702 Fin 20kg ([link])
The countertop will be cast in place, not to be turned. L-angle, approximately 8 m long, 80 cm wide, and 4.5 cm high.
How many bags are likely to be needed?
Is there someone skilled who can calculate this for me?
With proper reinforcement, there are no problems. Make sure to have a proper arm ring at the front and completely double layers of mesh in the corner.
Prime the entire slab first but no concrete against the front edge and possibly the sink. Do that last with the topping. Then it doesn’t matter if it’s not wet on wet and no joint will show. And as mentioned, at least 2 people and preferably 3. Make sure to cover adequately once you've finished working.
However, I don’t see the purpose of expansion mortar. I would have used coarse concrete with extra ballast and topped with fine concrete. That way you also have time to float the surface.
Prime the entire slab first but no concrete against the front edge and possibly the sink. Do that last with the topping. Then it doesn’t matter if it’s not wet on wet and no joint will show. And as mentioned, at least 2 people and preferably 3. Make sure to cover adequately once you've finished working.
However, I don’t see the purpose of expansion mortar. I would have used coarse concrete with extra ballast and topped with fine concrete. That way you also have time to float the surface.