How to Build an Interior Glass Block Wall
A glass block wall can create a division between rooms without blocking light.
Measure the area where the half (knee) wall will be located. Figure out the overall dimensions (width and height) of the half wall with the glass block top. Once the full dimensions are found, decide on the dimensions of the half wall, on top of which the glass block will sit. Chalk a line on the floor where thr wall will sit.
Cut the studs, top plate and bottom plate to the dimensions of the half wall. Cut the 2x4s using the miter or circular saw.
Note: The number of studs you’ll need will depend on the length of the wall.
Use the framing gun to nail the studs to the top and bottom plates. Space the studs 16" apart. Set the half-wall frame in place along the chalk line on the floor. Attach the frame to the floor and the side wall using the screw gun with 3" wood screws. Note: If the floor is concrete, use a hammer drill with a concrete drill bit and 3" concrete screws to secure the bottom plate.
Using a utility knife, cut the 1/2" drywall to fit the half wall. Secure the drywall to the studs with the screw gun and 1-1/2" coarse drywall screws. Keep the top edge of the drywall flush with the top of the top plate. Fill the screw holes with joint compound, let dry, then sand smooth.
If drywall is applied to both sides of the half wall, the total thickness of the wall will be 4-1/2". Rip the 1" x 6" down to a width of 5", which will give a 1/4" overhang on each side. Cut and attach the 1" x 5" clear pine to the unfinished top and end of the wall. Cut the end of each board at a 45-degree angle where they meet at the corner. Attach the 1" x 5" pieces by face-nailing them into the exposed 2x4s with the 18-gauge nail gun and 2" nails. Apply wood putty to the nail holes and sand smooth.
Test fit the glass blocks on top of the 1" x 5" and up the wall, using the spacers. Mark the locations where the blocks end (the last one on the 1" x 6" and the last one up the wall). Draw a center line up the wall and down the 1" x 5" to these marks.
Cut the horizontal spacer to length and center it on the line on the 1" x 6". Draw lines along both sides of the spacer. Remove the spacer and apply two 1/4" beads of sealant 1/4" inside the traced outline of the spacer.
Insert an anchor in the horizontal spacer and press it into the sealant. Do not attach the anchor with screws. Note: Check the product instructions for more details on the anchors.
Line up the first row of blocks and one end block on top of the horizontal spacer. Apply two 1/4" beads of sealant across the top of the blocks, just behind the raised edges. Note: These blocks will be turned over when installed so the sealant beads will contact the bottom horizontal spacer. Always apply the sealant to the blocks, not the horizontal spacer.
Apply four 1/2" dabs of sealant to one side of the first block, 1/2" from each corner. Press a vertical spacer into place on the sealant dabs. Apply four 1/2" dabs of sealant to the vertical spacer, 2" in from each corner. Install the next block with the sealant beads down. Continue installing blocks and vertical spacers in this manner to complete the first row.
Apply two 1/4" beads of sealant on top of the first row of blocks, just behind the raised edges. Install the second 31" horizontal spacer on top of the first row of blocks, with an anchor inserted into the wall end. Make sure the spacer fits firmly on the glass blocks. Press the spacer down onto the sealant.
Align the V notch in the anchor with the plumb line drawn on the jamb, and attach the anchor using the screws provided in the anchor pack. Remove any excess sealant from the horizontal and vertical joints. Adjust the size of sealant beads to prevent squeeze out (keep the joints clean of sealant). Do not change the location of the beads of sealant. Continue installing the block in this manner until the last block is set.
Mix the grout according to the instructions. Apply the grout to the glass block joints using the rubber float. Use clean water and a damp sponge to wipe up any excess grout, wiping in a circular motion. Let the grout dry and wipe the film off of the blocks.