Best answer

The application of vapor barrier in exterior concrete is unnecessary due to the fact that water penetration does not matter. Any slab on grade that is enclosed and on the interior of a building should have a vapor barrier installed prior to pouring concrete, especially if flooring will be applied.

Answered by: DryLabRebel Date created: Jun 23, 2022

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

Asked By: natemcmaster Date created: Jun 16, 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: Johannes Date created: Jun 17, 2022

Do you need stone under a concrete slab?

Asked By: Colin Ricardo Date created: Jun 10, 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: Mike M. Date created: Jun 11, 2022

Is concrete block waterproof?

Asked By: perreal Date created: Jun 20, 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: IBAction Date created: Jun 23, 2022

How do you waterproof a flat concrete roof?

Asked By: enet Date created: Jun 16, 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: fedorqui 'SO stop harming' Date created: Jun 17, 2022

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

Asked By: falmp Date created: Jun 21, 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: RavinderSingh13 Date created: Jun 24, 2022

What do you put on concrete floor before laminate?

Asked By: Paul Hankin Date created: Jun 12, 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: Gama11 Date created: Jun 14, 2022

Do you need plastic behind cement board?

Asked By: powtac Date created: Jun 19, 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: Levon Date created: Jun 19, 2022

Do you need a vapor barrier behind cement board?

Asked By: dogbane Date created: Jun 08, 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: Twisty Date created: Jun 11, 2022

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

Asked By: CB Bailey 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: Meno Hochschild Date created: Jun 11, 2022

Can I pour concrete around cast iron pipe?

Asked By: serv-inc Date created: Jun 09, 2022

You could just add a couple inches of sand, enough to handle the vapor barrier and then cover the pipe with a couple layers of plastic or roofing material and place the concrete right over the pipe.

Answered By: Eugene Date created: Jun 10, 2022

Related Question Answers

dev

Professor

Can plaster walls be insulated?

If your historic house has original plaster walls, you should not blow insulation into the exterior walls. Old houses with plaster walls have no vapor barrier under the plaster to stop moist air from saturating the insulation. Instead, plaster walls are designed to allow the free exchange of air and moisture.

Nicolas Gervais

Professor

How do you install moisture barrier under concrete slab?

Most exterior slabs do not need a vapor barrier. ... In general, place the concrete slab directly on top of the vapor barrier, with the subbase below. ... The vapor barrier can be placed under the subbase, if the building is closed in when the dry subbase material is placed.More items...

Paul Ogilvie

Professor

Do I need a vapor barrier between concrete and laminate flooring?

It is rolled out between the actual laminate flooring planks and the subfloor.

Very often, particularly in a below-grade installation on a concrete basement floor, a vapor barrier is recommended in addition to the underlayment.

That vapor barrier would go between the subfloor and the underlayment..

Ynetter

Professor

Do I need a vapor barrier between concrete and wood flooring?

Despite a successful moisture check and the presence of an underground moisture barrier, you still need additional protection from water vapor before laying a wood floor. Sheets of 6-mil thick polyethylene plastic, overlapped with seams taped, is one means of providing that moisture barrier.

Theraot

Professor

Do I need underlay on concrete floor?

Concrete bases need an underlay with a moisture barrier, a damp proof membrane (DPM) or a separate barrier to protect the floor from damp. If the sub-floor is wooden the choice of underlay will depend on what is being laid on top.

Tiago Martins Peres 李大仁

Professional

Do plaster walls need insulation?

If your historic house has original plaster walls, you should not blow insulation into the exterior walls. Old houses with plaster walls have no vapor barrier under the plaster to stop moist air from saturating the insulation. Instead, plaster walls are designed to allow the free exchange of air and moisture.

djechlin

Professional

Do plaster walls smell?

plaster is not a vapor barrier, so any odors in the walls can get in. it's good for the longevity of the plaster since it can breathe (if it gets wet, it can dry, for instance), but it won't keep the odors out.

animuson

Professional

Do you need Thinset under cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners.

And you won't have the fasteners if you are trying to install it over concrete..

Pranav C Balan

Professional

Do you need to seal a cement driveway?

Sealing the driveway yearly can lead to unsightly hairline cracks and peeling. And concrete driveways should be sealed every four or five years to protect them from water penetration and to prolong their life.

Sebastian Krysmanski

Professional

Do you need to seal a concrete driveway?

Sealing the driveway yearly can lead to unsightly hairline cracks and peeling. And concrete driveways should be sealed every four or five years to protect them from water penetration and to prolong their life.

Bertrand Martel

User

Do you need to waterproof cement board?

Although most backerboards currently available won't fall apart when exposed to moisture and are somewhat water-resistant, they aren't waterproof. To prevent moisture from seeping through to the wood or metal studs beneath the tile, a barrier or sealant must be used on porous materials.

Basil Bourque

User

Does stamped concrete scratch?

It is important to be careful where you install stamped concrete because it easily cracks and scratches under a heavy load. Stamped concrete is a poor choice for a driveway and any area on which cars are driven or parked.

Duncan

User

How concrete flooring is done?

Anatomy of a Concrete Floor This layer is covered with a vapor barrier sheet that prevents moisture from moving up into the concrete. A welded wire fabric mesh sheet is then placed over that in order to aid with adhesion. Finally, the concrete slab is poured directly onto these layers.

Antimony

User

How do you keep water from seeping on concrete floor?

Plastic drainage mats, or dimple mats, allow air to circulate under the flooring and provide a moisture barrier.

They also provide an insulating layer of air that separates the floor from cold concrete, reducing the potential for moisture damage from condensation or water vapor migrating through the concrete..

Gumbo

Guest

Should you seal concrete before laying laminate?

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.

mathematical.coffee

Guest

Does concrete stop radon?

Remember that even several inches of concrete cannot stop radon. Some builders believe that the plastic vapor barrier under the slab will stop radon. Although it is a part of the "radon resistant" construction, it merely reduces the flow of soil gas.

biberman

Guest

Do I need a permit to pour concrete in my back yard California?

In regards to your question, under the 2002 County of Los Angeles Building Code, section 106.3(15) states that a building permit shall not be required for “Platforms, walks and driveways not more than 30 inches (762mm) above grade and not over any basement or story below,” and as such, the driveway construction method ...

Ryan

Guest

How do I stop moisture in my concrete floor?

Methods Used to Stop Moisture in Concrete FloorsLow-permeance Vapor Barrier or Retarder.

A Low-permeance vapor Barrier or retarder can effectively keep below-slab moisture from reaching the flooring system.

...

Allow Natural Drying of Concrete Slab.

...

Keep Excavation Free of Water..

Daniel T.

Guest

Do you need underlay on concrete floors?

Most sub-floors will be either wood or concrete. Concrete bases need an underlay with a moisture barrier, a damp proof membrane (DPM) or a separate barrier to protect the floor from damp. If the sub-floor is wooden the choice of underlay will depend on what is being laid on top.

Cristian Lupascu

Guest

Is a vapor barrier necessary behind cement 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. ... You should NOT place a vapor barrier BEHIND the backer board.

Chris Saxon

Guest

Does cement board in shower need waterproofing?

“A waterproof membrane or vapor retarder membrane must be specified to prevent moisture intrusion and protect adjacent building materials.” ~B412 Bathtub or shower with prefabricated receptor. Cement board or Fiber-cement board. Ceramic Tile. ... Consult local building code for moisture barrier requirements.”

Guffa

Guest

Can you add cement to a gravel driveway?

Laying a concrete driveway over an existing gravel one is possible, but it is not generally recommended. ... The kind of gravel that is intended to go under cement is typically a smaller grade than what is used for gravel driveways.

MrTux

Guest

Do I need insulation under a concrete floor?

Creating an insulation layer and a vapor barrier between the concrete slab and the ground beneath it is the best practice in insulating basement floors.

The insulation barrier will help keep warm air in, and the vapor barrier will keep unwanted moisture out..

Jens

Guest

Should you put a vapor barrier behind cement board?

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.

tjebo

Guest

What is the best insulation for under a concrete slab?

Applying a bead of polystyrene-compatible caulk or mastic to the top of the insulation board minimizes water infiltration behind it. For under-slab applications, the rigid foam insulation typically should be installed over a gravel base, with a poly vapor diffusion retarder between the gravel and insulation.

colm.anseo

Guest

Should I seal concrete joints?

Stopping water from flowing under your concrete is probably the most important thing you can do to keep your driveway from sinking and becoming out of level. Caulking the joints and cracks is the best way to stop this from happening. Even expansion joints in your concrete driveway should be caulked.

dbenham

Guest

What do you put under a concrete driveway?

Use wire mesh for driveways that are 4 to 5 inches thick, and rebar for those that are 5 inches or more. Place rebar in a grid pattern with a spacing between bars of approximately 12 inches. In either case, blocks should be used under the reinforcement to keep centered within the concrete.

Taryn

Guest

What is the purpose of a vapor barrier under concrete slab?

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.

Nacho Justicia Ramos

Guest

Do I need DPM on concrete floor?

Do I need a DPM under laminate flooring? Simply put yes. In order to prevent damp rising through the concrete floor and causing issues, a DPM should be used under all final floor types including wood flooring, laminate, vinyl and floor tiles.

Cary Swoveland

Guest

How do you insulate lath and plaster walls?

Treat Your Gutted Walls Like New Construction When you have gutted your walls, install fiberglass batting, foam insulation or dense-pack cellulose insulation from the inside. Place a 4-mil plastic sheeting vapor barrier over all three of these types of insulations.

thatjeffsmith

Guest

Is concrete a Vapour barrier?

Actually, no. Air barriers need to be continuous and free from holes, but vapor barriers do not need to be. Lots of vapor moves by air movement, not a heck of a lot of vapor moves by vapor diffusion. The concrete slab is the air barrier, and the ripped and torn and punctured polyethylene sheet is the vapor barrier.

Aman

Guest

What can you cover concrete walls with?

Any gaps or cracks in your concrete floor and walls need to be sealed with cement. Special concrete coatings or a polyethylene membrane can also be applied as a barrier.

Ritwick Dey

Guest

Do you need concrete under pavers?

Installing pavers is very similar to concrete installation. You must start with a solid base and foundation. Most frequently, this involves digging down into the ground and removing the existing dirt and replacing it with gravel and sand.

nosklo

Guest

Do you need gravel under a concrete patio?

Yes! A strong gravel base is required when building a concrete patio in order to prevent the concrete from shifting or cracking. Adding gravel under the concrete also provides a level surface for your foundation and adds proper drainage when there is pooling water.

Lazar Ljubenović

Guest

Do you put plastic under concrete slab?

In California they place sand between slabs and plastic vapor barriers—in Florida they don't. Almost everywhere (except “California”) that slabs are placed on the ground—a plastic sheet—a vapor barrier—is located directly under the concrete slab and on top of the ground (Photograph 1).

Darkman

Guest

Do you need gravel under concrete footing?

Registered User. permanent wood foundations require gravel, not concrete or soil for the footings - every situation is a little different, but all footings need to bear on the soil/gravel/bedrock/ whatever is supporting the structure equally, or it's going to settle at different rates.

Rinto George

Guest

Can you use self leveling concrete on a driveway?

the simple answer is yes you can as long as you don't have a problem raising the floor height an inch or so. Regardless what the packages say, a coat of concrete under an inch thick has a tenancy to shell, crack and become a mess. If you do over pour, be sure to prep the existing concrete so you will get a good bond.

Lalit Kumar B

Guest

Do you need to put wire in a concrete driveway?

Wire mesh, like Rebar reduced the cracking and any uplift in the concrete driveway. Rebar will be used if there is a structural reason, meaning you need to carry the weight of the slab to pilings or plan to build above the slab. For a driveway, just use the wire, lap it one box around.

BatyrCan

Guest

Do you need to seal cement tiles?

Like natural stones, cement tiles are porous and therefore need to be sealed to avoid staining. Penetrating sealers coat the cement particles in the tile making it less likely they will retain stains. Topical sealers create a barrier on the surface of the tile so that stains do not reach the cement.

Lakshya Thakur

Guest

Do cement tiles need to be sealed?

Like natural stones, cement tiles are porous and therefore need to be sealed to avoid staining. Penetrating sealers coat the cement particles in the tile making it less likely they will retain stains. Topical sealers create a barrier on the surface of the tile so that stains do not reach the cement.

kshetline

Guest

How do I stop condensation in my concrete shed?

9 ways to effectively reduce garage condensationControl your garage's temperature. ... Use a vapor barrier. ... Dry your wet vehicle off after parking it in the garage. ... Check your ventilation. ... Inspect your drainage. ... Apply a floor coating. ... Install a dehumidifier. ... Get rid of that old garage fridge or freezer.More items...

Lion King

Guest

Do I need gravel under my concrete slab?

Whether you pour concrete for a walkway or patio, a strong gravel base is required to prevent the concrete from cracking and shifting.

Gravel is especially important in clay soil because it doesn't drain well, which results in water pooling under the concrete slab and slowly eroding the soil as it finally drains..

Christian Oudard

Guest

Do you need to use thinset under cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete.

brismuth

Guest

Is concrete slab waterproof?

Concrete slabs are not impervious to water. In fact, given the right environmental conditions, the floor slab can transmit gallons of water into the living space as vapor, and in extreme cases, actually show ponding water. ... The pre-construction solution is to use an underslab vapor barrier.

stackdon

Guest

Should I insulate plaster walls?

If your historic house has original plaster walls, you should not blow insulation into the exterior walls.

Old houses with plaster walls have no vapor barrier under the plaster to stop moist air from saturating the insulation.

Instead, plaster walls are designed to allow the free exchange of air and moisture.

Tomáš Zato - Reinstate Monica

Guest

Should I insulate under my concrete slab?

Creating an insulation layer and a vapor barrier between the concrete slab and the ground beneath it is the best practice in insulating basement floors. The insulation barrier will help keep warm air in, and the vapor barrier will keep unwanted moisture out.

haccks

Guest

Should you put plastic under concrete slab?

Recently, though, research has shown that the old traditional layer of 6-mil Visqueen (polyethylene plastic) under the slab is seldom effective for two main reasons: Although it may seem water-tight, this grade of material allows a lot of water vapor to pass through.