Most people enjoy a little sunlight to illuminate and heat a room. In rooms that don't already feature a window, spaces will need to be cut into the wall for window pane installation. In homes that feature brick walls, consider that the wall's integrity will be compromised, so consult your local building code authority before you begin.
Draw the exact measurement of your desired window opening, using light-coloured chalk. For straighter edges that are hard to attain on rough brick, use a yardstick placed flush to the wall and trace along its edging. Accommodate for the framing and include extra room in the measurement. The info for the measurement should be included on the packaging on the window assembly. Lay a dropcloth underneath the window space to catch dust and debris.
Adjust the blade depth on the brick saw to ½ inch and make a vertical cut into the right or left corner of the square or rectangular shape you drew in chalk. Make a slow pass with the saw to cut down from the left corner to the bottom corner.
Continue the cut around the perimeter of the window shape. Turn off the saw and readjust the blade setting to a full 1-inch depth and repeat the cut around the perimeter of the window shape. Continue cutting around the perimeter; apply a slight bit of pressure to the saw with each pass until the blade is fully submerged into the wall to ensure the brick is cut to the right depth.
Move the bricks out of the way that fall into the floor. Chances are several of the cut bricks will be loose; these are called bats and will need to be mortared back into their spaces before installing the window frame. Cut all the way to the plywood wall underneath the brick, cut the wood away and chip away rough edges around the bricks with a stone chisel to make the edges even and level.
Wear eye goggles, hearing protection, a dust mask and leather work gloves.