How to Install a Glass-Block Wall

Add some natural light to a room without sacrificing privacy with this project.

  1. Bricks


Tired of looking at the same four walls? Add a timeless touch to one of them. Here's how to fill an existing opening with glass blocks:

Materials and Tools:

two 8-foot 1-by-6-inch #2 pine boards
four 12-foot Colonial casings
25 8-by-8-inch glass blocks
10 4-by-8-inch glass blocks
painters' caulk
one gallon enamel latex trim paint
two tubes clear latex adhesive caulk
caulking gun
framing square
mortar trowel
mortar-smoothing tool
power miter box
speed square


1. Measure the opening for the glass wall and calculate the number of blocks needed. Glass blocks can't be cut, so work with full 8-inch increments.

2. Arrange the blocks on a table, using the spacers in the block kit, to get the actual size of the installation. Make a frame with 1-by-6s to enclose this group of blocks.

3. Cut 1-by-6 s to the length of the sides, and cut one to the length of the bottom plus 1½ inches. Assemble the frame with screws or nails.

4. Install the frame. Center the frame in the opening, blocking and shimming where necessary. Make sure the frame is square and level before attaching it to the opening.


5. Mix the glass-block mortar according to the directions on the package. Spread the mortar on the bottom and edge of the glass block, and then squeeze it into the corner using the spacers. Add blocks from left to right until the first course is finished.

6. Screw the metal retaining strips to the side frame and bend into place to fit between the rows of blocks. They're there to strengthen the wall and attach it to the structure.


7. Spread mortar on the entire first row of glass blocks, making sure the retaining strips are centered in the bed of mortar, and then push a reinforcing strip into the mortar. Hide the reinforcing strip so that it's not visible.


8. Lay the next course of glass block, and continue this process to the top.

9. Once the mortar has set up a bit, use a sponge and water to gently clean the block and shape the mortar with the mortar-shaping tool. The dust that dries on the block can be removed with a dry cloth.

10. After the mortar has hardened, run a clean bead of caulk around the perimeter of the block.


11. Install casing molding to cover the gap between the 1-by-6 frame and the original wall. Fill and paint the molding and frame.

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