Best answer

The use of a vapor barrier (more accurately termed a vapor retarder), having a water vapor permeance of less than 0.3 perm is frequently used to retard the flow of moisture through the slab. These vapor retarders are typically polyethylene or polyolefin sheeting materials.

Answered by: user3188445 Date created: Jun 24, 2022

Do I need a vapor barrier behind cement board in shower?

Asked By: arshajii Date created: Jun 22, 2022

Moisture barriers stop that water or vapor from getting any farther and potentially rotting your studs, the drywall or greenboard installed behind the enclosure. They are required beneath your shower pan and behind your shower walls.

Answered By: ronag Date created: Jun 23, 2022

Do you need stone under a concrete slab?

Asked By: Tanner Dolby Date created: Jun 22, 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: iconoclast Date created: Jun 22, 2022

Is concrete block waterproof?

Asked By: Cédric Julien Date created: Jun 15, 2022

Waterproofing Concrete Block Foundations. Concrete blocks and cinder blocks are much more permeable to water and water vapor than poured concrete. ... Block foundation walls will provide only a weak barrier against capillary water seepage and water vapor.

Answered By: Sam Saffron Date created: Jun 17, 2022

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

Asked By: Bram Vanroy Date created: Jun 19, 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: Inbar Gazit Date created: Jun 20, 2022

How do you waterproof a flat concrete roof?

Asked By: Vadim Gremyachev Date created: Jun 12, 2022

Step 1 - Clean Your Roof. In order to successfully seal your roof, you first need to start with a clean surface. ... Step 2 - Carry Out Minor Repairs. ... Step 3 - Use Seam Tape. ... Step 4 - Coat With Primer. ... Step 5 - Spray on a Vapor Barrier.

Answered By: emeraldsanto Date created: Jun 12, 2022

Do you need to seal a concrete floor before laying laminate?

Asked By: Stefan Date created: Jun 18, 2022

You don't need to seal a concrete floor before installing laminate; however, to prevent moisture from the concrete floor from affecting your laminate, install a vapor barrier of polyethylene film. Install this barrier even if the concrete subfloor is covered by vinyl, linoleum, terrazzo or ceramic tile.

Answered By: F1ko Date created: Jun 20, 2022

What do you put on concrete floor before laminate?

Asked By: Daryl Spitzer Date created: Jun 08, 2022

Begin installation by laying a plastic vapour barrier (minimum 6 mm thick) or any other manufacturer-recommended barrier on the concrete subfloor to prevent moisture from reaching the laminate flooring. Use vinyl tape to secure the barrier and keep it from coming out.

Answered By: Little Ball Date created: Jun 08, 2022

Do you need plastic behind cement board?

Asked By: thomasrutter Date created: Jun 15, 2022

Their online instructions/diagrams show no use of a vapor barrier. You should, so that any moisture that gets behind the cement board runs into the tub or shower instead of into your wall cavity (causing rot or mold/mildew).

Answered By: Ernest Friedman-Hill Date created: Jun 16, 2022

Do you need a vapor barrier behind cement board?

Asked By: diegoveloper Date created: Jun 09, 2022

You still need a vapor barrier with cement board, although in this case the barrier can go behind the board. Cement board is heavy enough and breathable enough to take the moisture without a problem. By having the vapor barrier behind the cement board you stop the moisture going further into the wall.

Answered By: paxos1977 Date created: Jun 10, 2022

Do you need to put a vapor barrier behind cement board?

Asked By: riccardo.cardin Date created: Jun 08, 2022

You should NOT place a vapor barrier BEHIND the backer board. Where, pray tell, would any such collected vapor/water go? Answer:There's nowhere proper for such moisture to egress. The current best practice is to place waterproofing OVER the backetboard and just UNDER the tile.

Answered By: Life is complex Date created: Jun 10, 2022

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Should you seal concrete before laying laminate?

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Does cement board in shower need waterproofing?

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...

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