Inspect the floor curb, if applicable. The curb width should match or exceed the width of the glass block units, and the curb should be fully wrapped in 15-lb. roofing paper or other waterproof covering. The most common curb construction is two or three stacked pieces of 2-by-4 or 2-by-6 framing lumber.
Prepare a small quantity of glass block mortar according to the manufacturer's specifications. It's handy to keep a small bucket of clean water close by to clean tools and rinse rags.
Spread a continuous layer of mortar over the entire length of the floor curb or wall length, approximately 1/2- to 3/4-inch thick and as wide as the center frosted portion of the glass blocks.
Start the first horizontal row, or "course," of glass blocks at the wall end of the floor curb. Spread a layer of mortar on the vertical side of the first glass block next to the wall surface and set the block in place.
Insert a block clip on the top leading corner of the first glass block. Block clips are inserted between each glass block as a uniform spacing device between blocks in a course and between courses. The plastic legs of the block clips can be broken off to adapt the clips to the ends of the courses or special circumstances.
Spread a layer of mortar on the vertical side of the next glass block to be installed, then set the block in place beside the previous glass block and tight against the block clip.
Insert a block clip on the top leading corner of the installed glass block and repeat steps 4 and 5 to complete the glass blocks in the first course. If you're using a manufactured end trim, be certain to keep the vertical end face of the glass blocks free of mortar.
Check the first course blocks for level, plumb, plus tight and consistent joint spacing. Adjust the blocks if necessary.
Bend an approximately 4-inch end section of metal anchor strap 90 degrees to create an "L" shape.
Position the longest arm of the metal strap on the top surface of the first course of glass blocks with the bent angle against the adjacent wall surface. Attach the metal strap to the wall with three 8D box nails. Repeat this strap-and-wall connection at every third course, to the top of the glass block wall.
Spread a continuous layer of mortar over the top of the previous course of glass blocks, including the anchor strap, approximately 1/2- to 3/4-inch thick and covering the space between the block clip's vertical alignment pegs.
Lay a strip of reinforcing bars, called "ladders," into the layer of mortar, end to end, to roughly 1 inch from the end of the wall.
Continue to lay or install the subsequent courses of glass blocks, repeating steps 6 through 12, as applicable, to complete the glass block wall. Check the plane of the wall as you build it, using a builder's level, to keep the individual glass blocks fully aligned and evenly mortared over the frosted area between the blocks.
Remove the mortar that has squeezed into the grout space between the glass blocks, using a pointer or small stick of wood to clear the grout space. Use a damp sponge and bucket of warm water to clean the mortar from the glass block grout surfaces.
Complete a final check of the wall plane for alignment. Use a rubber mallet to tap the glass blocks where adjustment is necessary. The curing mortar and block clips work together to strengthen the wall structure and hold its alignment.
Allow the completed wall structure to cure for a minimum of 48 hours before grouting the glass block joints.
Mix a quantity of glass block grout and apply it according to the manufacturer's specifications. Use a grout trowel to pack the grout into the joints, then a damp sponge to smooth and blend the finished surface between the glass blocks.
Follow the manufacturer's recommended curing time for the completed wall before exposing the wall to weight, such as a shower door frame, or the moisture of a steamy shower.
Things You Will Need
- Tape measure
- Reinforcing bars
- Block clips (spacers)
- Rubber mallet
- Glass block mortar
- Small masonry trowel
- Metal anchor strapping
- 8D sinker or box nails
- Clean cloth rags
- Buying or borrowing a few samples of the glass blocks in sizes you're considering helps greatly in designing the shape and defining the dimensions of your glass block shower wall.
- Lightweight, prefabricated glass block wall panels are also available in a range of standardized sizes that can offer a much less complex installation, possibly for less expense. Check with your local home improvement store or glass block supplier to explore this possibility for your application.