Drainable Housewraps: Added Defense Against Water Intrusion

Housewraps have been in the building construction market since the early 1970’s and continue to be the preferred choice of construction barriers for builders today. Architects insist on using housewraps as the most specified wall barrier products in the market. They perform excellently as water and moisture barriers and comply with local building codes throughout the U.S.. There have been many configurations of weather resistant barriers developed over the last 40 years, coming in many different types.

Drainable Housewraps

One type increasingly gaining momentum is drainable housewrap. These products are designed with some form of drainage plane integrated into the housewrap. There are many different types of drainage plane products on the market. Listed below are just a few currently on the market:

  • Crepe or corrugated housewrap – This style of housewrap utilizes a nonwoven breathable material that has been processed to create crinkles or raised edges in a vertical direction. These grooves serve as a drainage plane if bulk water gets behind the exterior cladding. This method works well as long as the product remains in the vertical position. If turned on its side it can lose the functionality of the drainage plane altogether.
  • Woven coated perforated and non-perforated housewraps with raised fibers placed in spaced increments – The raised fibers or monofilaments in these housewraps give enough off contact from the exterior cladding to allow water to drain down and out of the exterior wall. Again, these products work well as long as the material remains vertical. Forty-five or ninety degree angles could minimize their drainage field.
  • Spacers added to the top of the non-woven on a non-woven/breathable film composite – These products are relatively new to the market, with a 1mm gap created from the beads of polymer spaced on the surface of the housewrap. This gap allows for any bulk water that gets behind the exterior cladding to drain down the surface of the housewrap and out. This product also allows installation at forty-five and ninety degree angles with multi-directional drainablility. One downside to these housewraps is that the product only comes in five-foot widths, which can increase installation time.
  • Non-perforated reinforced microporous breathable film – This product has been in the market for over twenty years and was one of the first breathable housewraps on the market. Only until the last several years did the manufacturer begin to market the product with the reinforced mesh side facing out. The unique design of this mesh acts as a multi-directional drainage plane behind the exterior siding, allowing for installation at any angle. The product is also the only product in the market that is offered in High, Medium and Low Perm options, and comes in nine- and ten-foot widths.

Drainable housewraps were initially targeted to be used in regions with extreme conditions, such as wind-driven rain or locations with high temperatures, high humidity and excessive rainfall. However, builders are now determining that the best method to manage water that enters or accumulates behind cladding is to use some type of drainable housewrap to ensure the bulk of that water is eliminated.

Please click here to learn about the full line of drainable JX ALTA™ Housewraps.