Wall Construction & Reinforcement
Wythes, cavity walls, wall ties, brick ledges, corbels, lintels, CMU construction, bond beams, pilasters, grout, reinforcing steel, cleanouts, and control joints.
- Define wythe, cavity wall, and wall tie
- State standard wall tie spacing and cavity width requirements
- Describe lintels, corbels, and brick ledges
- Explain CMU construction including bond beams and pilasters
- Describe grouting procedures including low-lift grouting and cleanouts
- Explain the purpose of control joints and reinforcing steel
Lección 1
Wythes, Cavity Walls & Wall Ties
What Is a Wythe?
A wythe is a single vertical section of masonry one unit thick. A wall can consist of one wythe (single-wythe veneer) or multiple wythes. In multi-wythe construction, the wythes must be connected to act as a unified structural element.
Cavity Walls
A cavity wall consists of two wythes separated by an air space. The air space provides insulation value and a drainage path for any moisture that penetrates the outer wythe. Cavity walls are the standard construction method for commercial and institutional buildings.
The minimum cavity width is 1 inch. This minimum ensures adequate space for moisture drainage and prevents mortar bridges that could transfer water from the outer to inner wythe. Most designs use 2-inch to 4-inch cavities to accommodate insulation.
Wall Ties
The function of wall ties is to connect brick veneer to backup wall. Wall ties transfer lateral loads (wind, seismic) from the outer brick wythe to the structural backup while allowing differential movement between the two.
The standard spacing for wall ties is 16" x 24" maximum (one per 2.67 sq ft). This means ties are spaced no more than 16 inches vertically and 24 inches horizontally, providing one tie for every 2.67 square feet of wall area.
Closer Spacing Required
Wall ties must be spaced at maximum 8 inches around openings (windows, doors) and within 12 inches of any opening edge. High-wind zones may require even closer spacing per engineering.
Weep Holes
The purpose of weep holes is to allow moisture to drain from wall cavity. Weep holes are placed in the first course of brick above every flashing location - at the base of walls, above window and door heads, and above shelf angles. Typical spacing is 24 inches on center.
A wythe is a single vertical section of masonry one unit thick. A cavity wall has two wythes separated by an air space with a minimum cavity width of 1 inch. Wall ties connect brick veneer to the backup wall at 16" x 24" maximum spacing. Weep holes allow moisture to drain from the cavity.