Installing Lightweight Brick Veneer
It’s seldom possible to install a single-tier brick wall on an interior wall; floors simply will not support the weight. Even a basement floor can’t bear the weight; footings undergird only the foundation walls, not the slab. However, lightweight veneers can be applied to interior walls, and they look nearly as attractive as real brick. Because they are fire-retardant, you can often use them for firewalls behind wood-burning stoves. Check local codes.
Tools: Trowel recommended by manufacturer, hammer, mason’s line, line level, hacksaw with masonry blade, brush, jointer.
1. Apply the adhesive. Start in an upper corner of a wall. Spread a 1/8-inch layer of mortar adhesive over a 2x4-foot area. For outside walls, use roofing nails to nail a moisture barrier of 15-pound roofer’s felt and a layer of metal lath to the walls. Then trowel on a coating of mortar, working in 2x3-foot sections.
2. Install the bricks. Start at the top of the wall to ensure there will be a full course of brick where appearance counts. Attach a string running the length of the wall, held out from the wall about 1/2 inch, exactly one course down from the ceiling. Use a line level to make sure the string is level. If your ceiling is wavy or out of level, you may need to bring the line down a bit to make room for every brick. Press each brick into the adhesive, twisting it slightly to ensure a good bond. Align the bricks to the string. Leave 3/8 inch between bricks for normal-looking joints. To cut the bricks, use a hacksaw with a masonry cutting blade or rod.
Measurements - To determine if you must start with a full or a partial brick, divide the length of each brick, plus the width of the mortar joint, into the width of your wall. This will tell you how many full bricks you’ll need for each course. If the answer contains a remainder, you’ll need to start with a partial brick. The length of the first and last bricks should be the same, so divide any fraction of a brick by two to determine how long the starting brick should be. Avoid narrow fragments of brick. If the remainder is less than 4 inches, divide the remainder in half and trim that amount from the first and last brick in each course.
3. Strike the joints. Fill the joints between the bricks with more mortar adhesive or use a colored mortar of your choice after the adhesive has dried. Use either a pencil-type brush or a grout bag with the correct tip. Avoid smearing mortar adhesive on the face of the bricks; wipe up spills immediately. Once the joints have dried, coat the wall with a sealer recommended by the dealer.
Installing Stone Veneer
Liightweight stone veneers may be made of natural stone or cast from concrete and given natural-looking colors and textures. Stone veneer pieces range from 1/2 inch to 2 inches in thickness. With some lighter products, you can use an adhesive to attach the pieces directly on a finished interior wall. With heavier material, you’ll need to apply expanded metal lath and attach the pieces with mortar.
Tools: Hammer, tin snips, flat finishing trowel, plasterer’s rake or a homemade scratcher, brick set for cutting stone, jointer, brush.
1. Apply lath, first mortar coat. For interior walls, nail expanded metal lath directly onto the wall. For exterior walls, nail on 15-pound roofing felt, then metal lath. Trowel on a 1/4 inch coat of mortar over the lath. After the mortar has just begun to set up, roughen the surface with a rakelike tool, scratching it to a depth of 1/8 inch. Let this coat dry and cure for 48 hours before applying the next layer of mortar and the stone. Meanwhile, lay the stones out on the floor as they will be positioned on the wall. As you arrange them, keep the joint spaces consistent.
2. Apply stone veneer. Cover the scratch coat of mortar with a 1/2-inch layer of mortar, working with an 8-square-foot area at a time. Just before positioning each stone, also apply a thin layer of mortar to the back of the stone veneer. Press the stone into the mortar bed, moving it back and forth and rocking it slightly to create a thorough bond. Place the bottom corner stones first. Then, working upward, add pieces toward the center of the area you are veneering, keeping the joint space you established in your plan.
3. Strike the joints. As soon as the mortar has stiffened, but before it has set, use a jointer to strike the joints. Brush away the crumbs and burrs at the joint edges. Immediately clean any mortar off the face of stones with a damp rag and brush. Avoid soaking the mortar joints.