Is a vapor barrier necessary behind cement board?

If it's a cement board, you need a vapor barrier, because cement retains moisture, which means the wood next to it is always damp. It does retain moisture, but the advice given by others here is to move the waterproofing between the tile and cement board with products like Redguard or Ditra.

Do you need a vapor barrier behind Hardie board?

Depending on your local building authority having jurisdiction (the AHJ) over your building codes, vapor barriers are almost always required, whether your builder uses James Hardie products or some other, inferior product.

Do you need waterproof membrane on cement board?

First, you should provide a waterproof/resistant membrane against the wood studs before installing the concrete backer-board to protect the wood studs from moisture absorbed through the backer-board.

What do you put behind cement board in shower?

Unless specifically manufactured as a waterproof product, cement board is water resistant but not waterproof. You must coat it with a fluid-applied waterproofing or apply a water-resistant barrier behind it that drains (BSC 2009b).

Do I need a vapor barrier behind my shower?

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.

Vapor Barriers: Need one or not?

Do you put drywall behind cement board?

(Some cement board products may not require the underlying membrane if the seams are properly waterproofed.) In such wet areas, never install cement board directly over drywall or green board. Instead, first, remove the existing surface material, then install the cement board over the studs and membrane, as applicable.

Do I need a vapor barrier in my bathroom walls?

Because of moisture, bathrooms are some of the primary areas of your home at risk of mold and mildew development. It is important to make sure that a proper vapor barrier (or vapor retarder) is installed on the walls in your bathroom whenever you're building or remodeling.

Is RedGard a vapor barrier?

It bonds directly to clean metal drains, PVC, stainless steel and ABS drain assemblies and can be used as a slab-on-grade moisture vapor barrier under all types of floor coverings. RedGard® is a liquid-applied elastomeric waterproofing material that cures to form a monolithic membrane.

Do you need insulation behind shower walls?

When tubs and showers are installed on exterior walls, builders may forget to insulate and air seal the exterior wall behind the tub or shower surround. Neglecting to insulate and air seal here can result in significant heat loss and complaints from homeowners about tubs, showers, and bathrooms that are always cold.

Does shower pan liner go behind backer board?

The wallboard must be installed 1/8 inch above the shower pan. If the shower pan is not in place, the wallboard height must be guessed, which can lead to inaccuracies and an expansion gap that is too large or too small.

Does Durock cement board need waterproofing?

Water does not affect USG Durock® Brand Cement Board, however, TCNA guidelines recommend the use of a waterproof membrane in wet areas.

Should you waterproof cement board floor?

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.

What do I use to seal cement board before tiling?

The thin-set is a cement-based powder that you mix with water or latex additive to form a thick paste, which is used to seal the seams in the board and can also be used to set the tile.

Can Hardie board go directly on studs?

HardiePlank® lap siding can be installed over braced wood or steel studs spaced a maximum of 24" o.c. or directly to minimum 7/16" thick OSB sheathing. See General Fastening Requirements. Irregularities in framing and sheathing can mirror through the finished application.

What goes behind Hardieboard?

Joint flashing: James Hardie recommends that a slip sheet (joint flashing) is installed behind each butt joint in the siding. This is a 6” wide piece of weather resistive material to make sure that no water gets through.

What's better durock or Hardibacker?

What is this? HardieBacker is also the go-to choice when it comes to countertops and tile. Durock is too abrasive and can damage vinyl, porcelain, and enamel. HardieBacker does not contain any course materials, so it is the preferable choice.

What do I insulate behind a shower wall?

Sprayed insulation such as foam and cellulose are considered smarter choices compared to fiberglass, which tends to be more porous and susceptible to moisture retention. A foam pipe insulation can also be ideal for plumbing that runs behind shower walls as it keeps the pipes warmer during cold months.

Should bathroom interior walls be insulated?

Proper insulation will help keep your bathrooms a comfortable temperature year-round. Bathroom projects need special consideration because of the humidity and moisture that bathrooms generate. When moisture becomes trapped in walls, mold and mildew can grow, damaging your home and presenting a potential health danger.

Can I tile directly over redguard?

Can You Tile Directly Onto RedGard? There's no need to put another layer of product on top of RedGard before you begin tiling. A surface that has been painted with RedGard and allowed to dry is ready for you to apply thinset and install tile. You can install thinset mortar and tile directly onto RedGard.

Does drywall act as a vapor barrier?

The permeance of unpainted drywall is very high, generally between 20 and 90, so it's not a vapor retarder at all. Meanwhile, air leakage through a 1 square inch hole in a sheet of drywall allows 30 quarts of water vapor to pass through the drywall under the same conditions. A third of a quart versus 30 quarts.

Do interior walls need vapor barrier?

A vapour barrier is an important component in building construction. Its purpose is to help prevent water vapour from reaching building walls, ceilings, attics, crawlspaces or roofs, where it can condense and cause building materials to rot or grow mould.

What is the difference between a vapor barrier and a moisture barrier?

Moisture barriers function to help in preventing water from entering inside of the wall cavity. On the other hand, vapor barriers basically prevent water vapor from the interior of the house to filter through the wall and condense on the warm side of the insulation.