ᐅ Formwork blocks on the slab: should they be set in a mortar bed or not?

Created on: 5 Nov 2020 08:15

Hello everyone,
I have a base slab and now want to start building up with 24cm (10 inch) concrete formwork blocks. (It will be for a pool).

Should I set the first row of formwork blocks in a mortar bed and align them there, or should I simply align the blocks "dry" and then directly pour concrete with reinforcement for the first two rows?
Does it make a difference?

Thank you for your answers.

abc123455 Nov 2020 12:02

I simply lay the bricks in a mortar bed and align them there. The easiest way is to align each brick in the first row with shims. It’s enough to align the following rows with small shims.

nordanney5 Nov 2020 12:41

abc12345 schrieb:

I simply lay the bricks into a mortar bed and align them there, which is easier than aligning each brick in the first row with shims.
Is it enough if I then align the following rows with small shims?

Once the first row is properly aligned, the rest can simply be stacked like Lego, one row after the other. It’s similar to house construction, where nothing is aligned with shims anymore. ;-)

borderpuschl5 Nov 2020 13:09

That might work for 3-4 rows in a wall, but probably not for, I’d estimate, 8 rows for a pool where even a few millimeters (fractions of an inch) of dimensional deviation already matter.

nordanney5 Nov 2020 13:18

#10

borderpuschl schrieb:

That might work for 3-4 courses in a wall, but not for, I’d guess, 8 courses for a pool where a few millimeters (a few tenths of an inch) of deviation already matter.

It definitely does with proper execution ;-)

borderpuschl5 Nov 2020 14:16

#11

Unfortunately, this is not due to the workmanship but rather the tolerance of the formwork blocks.

knalltüte6 Nov 2020 19:58

#12

Hi, could you please start a pool construction thread with lots of pictures? I’m also planning to build a pool and would like to get some ideas. 😎

ᐅ Formwork blocks on the slab: should they be set in a mortar bed or not?

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