How to Add a Brick Wall to a Basement
Brick is decorative and durable. A brick wall creates an aura of permanence, for brick is one of the oldest building materials. Many brick buildings have stood for centuries. Once brick walls were solid layers, usually at least two bricks thick, and were a structural element supporting ceilings and roofs. Bricks also were often used to make basement walls. Today, virtually all brick walls are veneer, a layer of brick on a concrete or wood-sheathed wall, and basement walls are solid poured concrete or concrete blocks. Neither is as attractive as brick, so adding brick improves their appearance.
Make sure a concrete basement wall is sound and dry. Repair any cracks or breaks with a patching cement. Test for dampness by taping a sheet of plastic on the wall; let it sit for a day and see if any moisture has condensed behind it. Waterproof a concrete or concrete block wall with a coat of waterproofing cement of a type that will bond with mortar. Spread a thin layer of the cement over the wall with a rectangular mason's trowel and let it dry.
The bricks you'll used for a basement wall are thin bricks, real clay bricks fired just like full-sized bricks, but 1 inch or less thick. For a concrete or concrete block wall, you apply them with thin-set mortar. If you're re-doing a wood-sheathed interior basement wall, cover it with a waterproof membrane and metal lath and spread a 3/8-inch-thick base layer of waterproofing cement over the lath with a rectangular mason's trowel.
Use a tape measure and chalk line to snap level horizontal lines along the wall about every 8 inches as a guide for brick courses; thin bricks are about 2 1/4 inches deep and usually have a 3/8-inch grout line, so three layers will be 7 7/8 inches deep. Measure the wall first, however, and adjust grout lines so full bricks will cover the wall from top to bottom without any horizontal cutting.
Mix thin-set mortar, which comes dry in a package, with water; mix it in a large container so it is fluid enough to spread but firm enough to hold a thin brick in place. Test it with one brick before starting the installation and adjust the mix as needed. Mix mortar in small quantities and discard any that starts to dry and get crumbly.
Start at one end of the wall, at the top or bottom, depending on the recommendation of the brick manufacturer; some thin bricks are light enough to hold at the top, heavier ones may need to be installed from the bottom up. Spread mortar on the back of the thin bricks with the notched edge of a rectangular mason's trowel. Push each brick firmly into the wall until it will hold, then move to the next brick. Lay bricks in any desired pattern; the most common style is "running bond" with each brick overlapping two other bricks by half a length. Put plastic tile spacers between brick corners if desired to help keep mortar lines even.
Begin the second row with a half-brick to provide the needed offset. Cut bricks with a masonry wet saw or a circular saw with a special masonry blade. Put the cut edges against a mortar joint, not the outside edge of a wall. Cover the entire wall with thin bricks and let the mortar cure overnight.
Fill the spaces between bricks with mortar grout. Use a cloth grout bag with a pointed metal tip, much like a baker's cake-decorating bag. Squeeze grout into every joint until the seam is filled. Finish by smoothing the grout with a steel brick finishing tool with a convex tip to make a concave joint or with a thin square-end tuckpointing trowel or a square wood stick for a square joint. Wipe off any excess grout with a damp sponge.
- Patching cement
- Plastic sheet
- Waterproofing cement (optional)
- Waterproofing membrane and metal lath (optional)
- Cement plaster
- Rectangular mason's trowel
- Tape measure
- Chalk line
- Thin bricks
- Thin-set mortar
- Masonry wet saw or circular saw with masonry blade
- Mortar grout
- Grout bag with metal tip
- Steel brick finishing, tuckpointing tool or wood with square end
- Damp sponge