Best answer

The sand layer cannot dry downwards by vapor diffusion because of the plastic sheet—it is a vapor barrier after all. In fact that's why we have it under the slab. We want a vapor barrier under the slab. ** We want to prevent water vapor from coming up from the ground into the concrete slab.

Answered by: Paul Sasik Date created: Jun 24, 2022

Do you need stone under a concrete slab?

Asked By: Eric Leschinski Date created: Jun 13, 2022

Because concrete is a very porous material, it will absorb any moisture that it contacts. This can cause pooling. Without crushed stone, pooling water will settle under it and erode your slab. Adding a layer of crushed stone will add proper drainage, as well as create a barrier between your slab and the ground.

Answered By: Martin York Date created: Jun 15, 2022

What is normal concrete cracking?

Asked By: TarkaDaal Date created: Jun 19, 2022

Probably the single most common reason for early cracks in concrete is plastic shrinkage. When the concrete is still in its plastic state (before hardening), it is full of water. This water takes up space and makes the slab a certain size. As the slab loses moisture while curing it gets a bit smaller.

Answered By: Barbaros Özhan Date created: Jun 21, 2022

What is the difference between plastic cement and Portland cement?

Asked By: David Date created: Jun 07, 2022

The difference between portland cement and plastic cement is minute. Plastic cement is a portland cement but the difference is in the addition of material introduced in the finish grind. Normally a plastic cement will include the addition of air entraining agents or other additives in the process.

Answered By: ktiu Date created: Jun 07, 2022

Should you cover concrete with plastic?

Asked By: friederbluemle Date created: Jun 22, 2022

Plastic Sheeting Can Permanently Discolor Concrete. Adverse weather conditions such as rain, snow, or freezing temperatures often make it necessary to protect concrete by covering it. ... That's what makes curing concrete with plastic so effective: the plastic keeps the concrete damp.

Answered By: CRice Date created: Jun 25, 2022

How much does it cost to replace a sewer line under a concrete slab?

Asked By: fsimonjetz Date created: Jun 12, 2022

The cost to replace a sewer line under a slab costs $3,000 to $5,000 for smaller jobs and $15,000 to $20,000 total for larger jobs.

Trenching under a slab can cost an extra $150 to $200 per foot..

Answered By: Chris Halcrow Date created: Jun 13, 2022

How can you tell if a concrete floor is dry?

Asked By: Panagiotis Kanavos Date created: Jun 13, 2022

To use this method, ASTM D 4263, “Standard Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method,” a plastic sheet is tightly taped to the concrete. After 72 hours, a humidity reading is taken under the plastic with a dew point hygrometer.

Answered By: Alex K. Date created: Jun 13, 2022

What do you put behind cement board in shower?

Asked By: SilentGhost Date created: Jun 09, 2022

Cement Board and a Liquid Membrane No plastic sheeting goes behind the cement board.

A liquid waterproofing membrane, such as RedGard or Hydro Ban, is applied to the cement board and allowed to cure.

Then, tile is installed over the membrane..

Answered By: Michael Hoeller Date created: Jun 10, 2022

Can a concrete slab be too thick?

Asked By: Gulam Hussain Date created: Jun 22, 2022

If the slab is too thin, it may break under load and fail before its time. If the slab is too thick, it costs more than it should. Slab thickness is a major factor in the cost of a concrete floor, so there's often pressure, which can become intense, to make the slab as thin as possible.

Answered By: Fizer Khan Date created: Jun 22, 2022

Can concrete cure under water?

Asked By: Marco Bonelli Date created: Jun 14, 2022

Water Cure Concrete made with Portland cement will harden even if it is completely under water.

In fact, one technique for curing a concrete slab is to build a soil dam around the perimeter of the slab, flood the slab with water and keep the slab covered with water for a week..

Answered By: Ben Butterworth Date created: Jun 14, 2022

How do you fix concrete after it rains?

Asked By: Wais Kamal Date created: Jun 21, 2022

Most damage done to concrete by rain can be fixed by removing the affected layer with specialized tools.Cover the concrete with plastic sheeting as soon as possible after the rain starts.

...

Remove the plastic once the rain has stopped and allow the concrete to dry fully.More items....

Answered By: nanofarad Date created: Jun 21, 2022

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