Masonry

Essentials of
Masonry

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Part 2--Construct a Concrete-Block Wall

LINTELS, SILLS, AND REINFORCING STEEL

Lintels, sills, and reinforcing steel are frequently used in construction.

2-27. Lintels. Lintels are placed across the top of door and window openings to support the walls above the openings. Precast concrete lintels are often used over door and window openings;(Figure 2-29).

Figure 2-29. Precast lintels without offset

a. Offset Lintels. For modular window and door openings, you will often use precast concrete lintels designed with an offset on the underside. Steel angles are also used with lintels to support blocks over openings. You must install the blocks with the offset on the underside to fit modular openings (Figure 2-30).

Figure 2-30. Precast concrete lintels with an offset

b. Metal Pates. Place a noncorroding metal plate under the ends of lintels wherever there are control joints. This permits lintels to give slightly and helps the control joints to function properly. Place a full bed of mortar over this metal plate to distribute the lintel load evenly.

2-28. Sills. You will usually install precast concrete sills after you have built the walls. Be sure to tightly fill the joints at the ends of the sill with mortar or a caulking compound (Figure 2-31).

Figure 2-31. Precast concrete sills

2-29. Reinforcing Steel. You can use steel bars to reinforce lintels and beams and to support the wall against abnormal stresses, such as an earthquake or strong winds.

a. Lintels and Beams. Lintel blocks can be used for constructing reinforced block beams or lintels. Lay the blocks end to end to form a channel. Place reinforcing bars in the channel and then fill the channel with concrete or mortar. You can either cast the beam or lintel in place on the shoring or precast and install it later (Figure 2-32).

Figure 2-32. Lintels made with concrete blocks, mortar, and reinforcing steel bars

b. Vertical Steel. Use vertical steel bars in the corners and around door and window openings. Figure 2-33 shows the placement of both vertical and horizontal steel reinforcing bars.

Figure 2-33. Placing reinforcing steel

Primary Content Provider: U.S. Army
Publisher: SweetHaven Publishing Services