Is stucco an air barrier?

When detailed correctly at penetrations and transitions, stucco can function as an effective exterior air barrier.

Is stucco a weather barrier?

Three-coat stucco is the most common exterior cladding here in Southern California; properly installed, it's tough, durable, and attractive. But it's not waterproof. No matter how skilled the plasterer is, rain will get behind stucco.

Does stucco need an air gap?

Stucco and thin stone with continuous rigid insulation should take cues from EIFS—having an air gap to drain behind the rigid insulation is important, as moisture could potentially migrate there from the interior (as vapor) or from the exterior (in liquid or vapor form).

What materials are considered air barrier?

Air barriers are intended to resist the air pressure differences that act on them. Rigid materials such as gypsum board, exterior sheathing materials like plywood or OSB, and supported flexible barriers are typically effective air barrier systems if joints and seams are sealed.

Is stucco vapor permeable?

Because modern Portland-based stucco is not vapor-permeable and it traps moisture. Natural plasters, such as clay and lime, are much more permeable.

Weather Barrier Vs Air Barrier Vs Vapor Barrier - What's the difference?

What goes behind stucco walls?

Sheathing is basically the “backing material” that can be found underneath the various layers of stucco that form the backing of residential and commercial buildings. They can be made out of wood, cement, gypsum, fiberglass and other materials.

What do you put behind stucco?

Because stucco is porous, the base—typically plywood or oriented-strand board sheathing—must have at least one layer of weather-resistant, vapor-permeable asphalt-impregnated building paper (“felt”) or plastic-based building wraps or stucco wraps.

Which material is not an air barrier?

A wide variety of materials make good air barriers, including poured concrete, glass, drywall, rigid foam insulation, plywood, and peel-and-stick rubber membrane. (Note that evidence is increasing that OSB is not an air barrier; for more information on this issue, see Is OSB Airtight?)

Is drywall considered an air barrier?

Gypsum board drywall is, itself, a suitable air barrier material. The taping of drywall seams results in a plane of airtightness at the field of the wall. However, several steps must be taken to use this material property to create a continuous and complete air barrier system.

Does stucco need a drainage layer?

One-coat (synthetic) stucco over a cementitious backer board can work well, but it must have intentional drainage behind it. For traditional three-coat stucco, building codes often require two-layers of building paper behind the stucco.

Does stucco prevent moisture?

Stucco itself is fairly waterproof on its own, but stucco walls and openings in those walls need to be correctly installed in order to achieve true waterproofing.

How do you keep moisture out of stucco?

“A weep screed is a type of building material used along the base of an exterior stucco wall. The screed serves as a vent so that the moisture can escape the stucco wall finish just above the foundation.

Should you paint over stucco?

While you would resort to paint to protect many kinds of materials, stucco is one material that is not well matched with paint. For starters, because it readily absorbs moisture, the stucco sucks up all the paint and you need to apply many coats to cover the surface. The problem is most severe in humid climates.

Should I seal stucco?

Sealing your stucco is a great way to prevent water absorption. New stucco should be sealed with a clear concrete masonry sealer, typically made of a silicone material. For older stucco that's already showing signs of cracking, waterproof elastomeric paints are an excellent choice to preserve and protect your stucco.

What kind of paper goes under stucco?

10-Minute Building Paper is ideal for use as a weather-resistant barrier when installed behind stucco or other exterior wall cladding. GMCraft is asphalt saturated building paper.

What can be used to create a continuous air barrier within a house?

Airtight Drywall.

The most common interior system, especially in light construction, uses sealed drywall and is referred to as the airtight drywall approach, or ADA. This approach builds on the typical drywall installation, in which the drywall and joint compound provide a continuous air barrier.

Where should air barrier be installed?

Con: Ideally, air barriers should be installed on the 'cool' side. However, if used on the warm side, the ideal way to ensure that polyethylene is effective as an air barrier requires the sheeting to be sandwiched between two layers of drywall, meaning added cost.

Is Tyvek an air barrier?

No, DuPont^™ Tyvek^® is not a vapor barrier. It is made with unique material science to keep air and bulk water out while allowing moisture vapor inside walls to escape.

What is the difference between air barrier and weather barrier?

While vapor retarders and air barriers are intended to control moisture condensation within wall assemblies, weather-resistive barriers (WRBs) are intended to prevent the penetration of liquid water through the exterior walls.

Is paint an air barrier?

All of these paints served as adequate vapor barriers (where ap plied in two coats) to keep moisture in walls at acceptable levels. Labeling commerical paints with perm ratings would help the con sumer determine those most suitable for use as vapor barriers.

How thick is an air barrier?

AIR-SHIELD self-adhering air/vapor and liquid moisture barrier is a part of a total system to complete the building envelope. It is a roll-type product that is nominally 40 mils thick.

Is plywood required under stucco?

When stucco is applied over any engineered wood sheathing, the wood sheathing must cover the entire surface which will receive the stucco. It doesn't work to only use plywood in the corners, with Styrofoam sheathing in-between. The Styrofoam isn't strong enough to support the stucco.

Is stucco over brick a good idea?

Stucco and brick are from the masonry category. But generally speaking, applying stucco over the brick is quite acceptable and it can generate excellent results. In fact, stucco provides a durable finish that can effectively cover brick. It can even enhance its appearance.

Can I put stucco over concrete?

Stucco needs to be applied to a sturdy, stable surface in order to ensure that it doesn't crack or crumble. If you apply stucco to a wooden surface, you must first install a metal netting to hold the stucco, but it can be applied directly onto a concrete surface.