Multiple sheet building wrap for use in external wall assemblies having wet-applied facades

Abstract

A multiple sheet building wrap for wrapping the structural components of a building in order to protect the underlying structural components and optional building sheathing from moisture is provided. The building wrap is particularly useful under facades such as wet applied stucco or engineered stone, demonstrating good drainage of liquid water and moisture vapor permeability. The building wrap is a composite of a water resistive barrier, a three-dimensional mesh layer and a porous intervening layer which acts to filter the stucco as it is applied. An exterior wall construction incorporating such building wrap is also provided.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a building wrap for wrapping the structural components of a building in order to protect the structural components and optional building sheathing from moisture.[0003]2. Description of the Related Art[0004]Two sheets of a water resistive barrier (“WRB,” also commonly referred to as “weather-resistive barrier” or “house wrap”) material are known for use as a building wrap under facade materials such as three-coat stucco or traditional Portland cement which are applied wet, e.g., using a trowel or by spraying. For instance, such building wraps can include two layers of Grade D building paper, two layers of asphalt-saturated kraft paper, two layers of building felt, two layers of a conventional polymeric house wrap, or one layer of building paper combined with one layer of polymeric house wrap. Known polymeric house wraps for use as WRBs include, for example, spunbond polyethylene sheet ava...

AI Technical Summary

Problems solved by technology

The mesh layer of these systems allows the wet-applied stucco to penetrate the mesh, thereby interfering with the drainage of liquid water through the mesh and inhibiting the transport of moisture vapor through the water resistive barrier.