Best answer

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...

Answered by: Gert Arnold Date created: Jun 25, 2022

Do you need stone under a concrete slab?

Asked By: drAlberT Date created: Jun 12, 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: abccd Date created: Jun 12, 2022

How do you run a pipe under a concrete slab?

Asked By: Jacob Relkin Date created: Jun 09, 2022

In six simple steps you can dig under concrete:Attach drill pipe.Connect garden hose.Dig a small ditch.Start your bore.Add more drill pipe (if necessary).Pull piping through.

Answered By: Dinesh Balasubramanian Date created: Jun 12, 2022

How do I get rid of rats under my concrete slab?

Asked By: lomaxx Date created: Jun 14, 2022

Answer: If the patio slab is not connected to the house slab you can use a Giant Destroyer to help eliminate the rat. If there are many tunnels or if it is in an area where you cannot seal up the entrances you may want to consider using rat poison baits instead such as Fastrac or Contrac.

Answered By: Triptych Date created: Jun 17, 2022

Does sealing concrete stop moisture?

Asked By: swatchai Date created: Jun 18, 2022

What are Concrete Floor Sealants Used For? Floor sealants are a very effective moisture mitigation solution. They're used to seal the concrete subfloor and create an impermeable barrier between the subfloor and your flooring.

Answered By: TmTron Date created: Jun 20, 2022

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

Asked By: thefourtheye Date created: Jun 24, 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: Jaswant Singh Date created: Jun 27, 2022

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

Asked By: Tural Ali Date created: Jun 07, 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: Pengyy Date created: Jun 10, 2022

How do you install a plywood subfloor on a concrete slab?

Asked By: James Lin Date created: Jun 24, 2022

Installing a subfloor over concretePlace the first plywood layer with edges parallel to wall, without fastening. ... Plywood panels should be placed with 1/8” gaps between sheets.Lay the second layer perpendicular or at 45 degree angle to the first.More items...

Answered By: Marek Urbanowicz Date created: Jun 25, 2022

How do you install sleepers on a concrete floor?

Asked By: crayxt Date created: Jun 12, 2022

Place the sleepers in mastic around the room's perimeter, abutting their ends. Secure them to the slab with 2 1/4-inch powder-actuated fasteners or masonry nails. Using the same methods, place sleepers across the slab on 16-inch centers, perpendicular to the direction the finish flooring will run.

Answered By: JD D Date created: Jun 12, 2022

What do you put on concrete floor before laminate?

Asked By: Yuriy Faktorovich 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: Chris Date created: Jun 11, 2022

What is the best flooring to put on a concrete floor?

Asked By: slago Date created: Jun 08, 2022

Like other flooring materials that work well over concrete slabs, laminate uses layers to fight moisture. This makes it a reliable option to install over your concrete slab. If you plan to transform your basement into a high traffic area for entertaining and relaxing, laminate could be a great option.

Answered By: Vitalii Fedorenko Date created: Jun 09, 2022

Related Question Answers

Paul LeBeau

Professor

Do you need plastic behind cement board?

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).

pearpages

Professor

Do you need 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.

Vijay

Professor

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

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.

Kuba hasn't forgotten Monica

Professor

Is Thinset under cement board necessary?

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.

yatu

Professor

What do you put on concrete floor before vinyl?

Perhaps the easiest way to improve the insulation of a floating vinyl floor on concrete is to install a thermal underlayment, preferably made of cork, felt or a similar material. If you use an underlayment without a moisture barrier, it's a good idea to install a sheet of plastic below it for insurance.

David Bradshaw

Professional

Are plaster walls waterproof?

It is water soluble and, without care, can succumb to moisture and humidity. Although interior plaster can never totally be waterproofed, there are some steps that you can take to create a stronger moisture barrier.

hammar

Professional

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.

Stefan Svrkota

Professional

How do I find a water leak under a concrete slab?

Signs Of A Leak Under Concrete1). There is water or damp spots on your floor. If hot-water lines are leaking, this may also lead to warm spots on your floor. ... 2). You can hear the sound of rushing water underneath your floor. ... 3). There is a significant increase in your water bill.Jan 10, 2021

Jonas Wilms

Professional

How do you fix moisture in a concrete slab?

Installing sub-drains at the building perimeter to carry water away from a building: This technique incurs some cost but is the most effective solution to tackle any further detrimental effect of moisture on the concrete slab. Place a vapor retardant underneath the new floor finish.

G M

Professional

How do you install concrete expansion joints?

The easiest way to add expansion joints is to do it during the pouring of your cement slab. As you finish pouring each section of your driveway, slip an expansion joint into the form between the section you've just poured and the section you are about to pour.

Whole Brain

User

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.

Johan

User

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.

solarissmoke

User

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.

Bathsheba

User

Do you have to seal cement board in a tile shower?

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..

Daryl Spitzer

User

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..

Dharmesh Kheni

Guest

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.

jfaccioni

Guest

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.

James Lin

Guest

How do you install porcelain tile on a concrete patio?

How To Install Tile Over An Existing Concrete PatioMaterials:Step 1: Prep your surface.Step 2: Do a dry-lay.Step 3: Install your tile.Step 4: Grout your tile.Step 5: Seal your grout.Step 6: Enjoy your new patio!Jul 25, 2017

Rabbid76

Guest

How do you install solid wood flooring on a concrete slab?

Lay 6-mil polyethylene sheeting over the concrete to minimize moisture migration from the concrete up into the wood flooring. Then fasten 3/4-in. treated plywood to the concrete with concrete screws spaced every 16 in. Alternatively, screw rows of treated 1x4s to the concrete 16 in.

Parryla

Guest

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..

Joris Meys

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.

PeeHaa

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.

Carlos Andres

Guest

How do you run a conduit under a concrete slab?

Select a pipe of sufficient diameter for the desired excavation width. ... Dig a small trench on each side of the concrete slab. ... Measure the width of the concrete slab. ... Push the angled end of the PVC pipe into the soil in the trench on one side. ... Tap the other end of the PVC pipe with your sledge hammer.More items...

bikram

Guest

How do you install drain pipe in concrete floor?

How to Install a Floor Drain in a Concrete SlabPrepare Your Space. While it's easiest to install a floor drain prior to pouring your cement, you can do it after the floor has been set. ... Plan Drainage. New floors are easier to plan, as you can lay out the pipes in place and then install the floor over top. ... Dig Trenches. ... Pour New Concrete. ... Add a Drain Cover.Aug 19, 2020

N Sharma

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..

ely

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.

kahowell

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.

Sayse

Guest

How do you prevent moisture problems in concrete floors?

How to Prevent Moisture Problems on Concrete FloorKeep a low water to cement ratio. ... Take all necessary actions if pouring concrete below grade or at a wet building site. ... The layers above and below the concrete slab to prevent water seepage into the slab. ... Give the concrete slab the time it needs to dry and cure.

thdoan

Guest

Can you put footings under concrete slab?

edit - To put footings under the slab, you can cut holes wherever needed, excavate for footings (Sonotubes or concrete piers or similar) and then patch the concrete slab.

npocmaka

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..

First Zero

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.

ozgur

Guest

How do you build an existing concrete slab?

How to Build a Shed on an Existing Concrete SlabStep 1: Check Condition of the Slab.Step 2: Plan Your Build.Step 3: Build Shed Walls.Step 4: Install Sill Gaskets.Step 5: Install Walls..

Vaccano

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.

Swati

Guest

What is the best flooring to put over a concrete slab?

laminateLike other flooring materials that work well over concrete slabs, laminate uses layers to fight moisture. This makes it a reliable option to install over your concrete slab. If you plan to transform your basement into a high traffic area for entertaining and relaxing, laminate could be a great option.

mao

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.

NathanOliver

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.

Sheharyar

Guest

How do you break concrete slab by hand?

InstructionsDig Under the Concrete. Dig out the soil, gravel, or other material from under the concrete, using a shovel and a pickax. ... Strike the Concrete. Lightly sprinkle the concrete with water to minimize dust. ... Pry Off Stubborn Pieces. ... Move the Concrete Chunks With a Hand Truck.Feb 19, 2020

evanmcdonnal

Guest

Can you add footers to a concrete slab?

edit - To put footings under the slab, you can cut holes wherever needed, excavate for footings (Sonotubes or concrete piers or similar) and then patch the concrete slab.

Amit Prajapati

Guest

Do you need a vapor barrier under concrete driveway?

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.

Engineer

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).

Mawg says reinstate Monica

Guest

Will concrete crack without rebar?

Really depends on what the slab is used for but in general no you can install wire mesh or use fibered concrete. However you do need something to tie the concrete it just doesn't have to be rebar. You do not need rebar for any slab if you make it thick enough and space the joints properly. ... Any concrete slab can crack.

Razor

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...

Pashyant Srivastava

Guest

What happens if you pour concrete on dirt?

The clay can compress under the weight of the concrete, causing the slab to shift or sink over time. It also can leach moisture from the concrete itself, resulting in uneven curing and a brittle base. With proper preparation, however, it's possible to pour a slab on clay soil without encountering these problems.

BinaryMisfit

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..

Gilles 'SO- stop being evil'

Guest

Can I pour concrete against pressure treated wood?

Yes, but you should also have a insulating barrier between the concrete and the wood. Pressure treatment is generally to kill bugs and reduce fungi but it will still absorb moisture through the concrete if it is there. By insulating between them, the chances of moisture transferal is greatly reduced.

peter flanagan

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.

PCM

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.

Karol Majewski

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.

Arnaud Le Blanc

Guest

Should you wet cement board before tiling?

The concrete is unaffected by any water that manages to get behind the ceramic tile. But these concrete products are heavy, problematic to cut and can wick water, causing wood rot. ... If you use cement backer board, you have to install a separate moisture barrier between the board and any wood it's attached to.