Raising swimming pool floor to form a shallow end

[AJBangkok]

I am thinking of raising the floor of my pool at one end by 20cm to form a shallow area where people can stand confortably. The area is approximately 20 square meters. There are no pipes or drains in the area.

The contractor has suggested a bed of sand of 7cm and then rebar and cement for 13cm.

I thought they would just chip and rough the floor, add rebar then use a lanko bond before application of the concrete.

I don't know why the bed of sand and am worried that in the future it could settle and cause cracks or problems.

Could anyone explain why the sand and if that's the best way to do this.

Thanks

[Rdteth]

Maybe you ask your contractor how he would split when you want a 40 cm higher floor.
I guess he will just add more sand.

[Sometimewoodworker]

I am thinking of raising the floor of my pool at one end by 20cm to form a shallow area where people can stand confortably. The area is approximately 20 square meters. There are no pipes or drains in the area.

The contractor has suggested a bed of sand of 7cm and then rebar and cement for 13cm.

I thought they would just chip and rough the floor, add rebar then use a lanko bond before application of the concrete.

I don't know why the bed of sand and am worried that in the future it could settle and cause cracks or problems.

Could anyone explain why the sand and if that's the best way to do this.

Thanks

He probably wants to do it that way because sand is much less expensively per cubic metre

[Breizh29]

I am thinking of raising the floor of my pool at one end by 20cm to form a shallow area where people can stand confortably. The area is approximately 20 square meters. There are no pipes or drains in the area.

The contractor has suggested a bed of sand of 7cm and then rebar and cement for 13cm.

I thought they would just chip and rough the floor, add rebar then use a lanko bond before application of the concrete.

I don't know why the bed of sand and am worried that in the future it could settle and cause cracks or problems.

Could anyone explain why the sand and if that's the best way to do this.

Thanks

He probably wants to do it that way because sand is much less expensively per cubic metre

I agree with that. But OK what I say!

[Klondyke]

In fact, any hard filling material can do, mostly by stones, gravel. However, in Thailand the stones are not everywhere available and/or not cheap, so easy for the Contractor is to purchase a truck of sand. And easy for him to spread up.

Stones can be substituted by debris of concrete, bricks, cements blocks. This is everywhere available around villages from various demolitions. Unlike in our old good world here in Thailand you will never see using recycled bricks or blocks for any building. Not only from laziness but mainly because the bricks/blocks are connected by very strong cement mortar impossible to clean it off, unlike as in our old good world with a lime mortar. (most of the damaged houses after WW2 were rebuilt by recycled bricks.)

The underlying bed by stones, debris, some 10 cm, when compacted and covered 3 cm sand gives more guarantee against settlement. Then the upper concrete layer can be 7 - 10 cm. Lanko bond just for the connection stripe (in slope) to the existing floor.

[AJBangkok]

Thanks everybody the contractor has come back with a method statement using all concrete