How to Build With Glass Blocks
Glass blocks create attractive windows and walls that allow light through while providing privacy to an area. They can be used in almost any building element except load-bearing walls. These include projects such as an island or bar support, shower or tub windows. Glass blocks cannot be cut to size, so the worker must take this into account and provide adequate framing material to fit the end result. Colored lighting can be used with the glass blocks to provide a striking accent to a room at night. Does this Spark an idea?
Other People Are Reading
Things You'll Need
- Measuring tape
- Framing material (as wide as the glass block)
- Fine tooth saw
- Metal file
- Screwdriver
- Screws
- Joint tape or expansion foam
- Glass block channel
- Tin snips
- Glass block cement mortar
- Margin trowel
- Mortar pan
- Polyfoam brush
- Level
- Sponge
- Spacers (the type depends on the type of glass block being used as they are specific to each manufacturer)
- 3/8 to 1/2-inch striking tool
- Caulking gun
- Glass block sealant
- Decorative molding (optional)
Instructions
-
-
1
Using the measuring tape, calculate the number of glass blocks required for the area where they will be used, as per the manufacturer's recommendation. Take into account the size of the glass blocks, framing material, and the area taken up by the seams in between each block, if necessary. Some glass blocks include these measurements already.
-
2
Install the framing material. This includes wood strips to make the opening the correct size for the glass blocks as well as the joint tape or expansion foam recommended by the manufacturer. This helps with temperature-related expansion and contraction of the glass block panel. The manufacturer may also recommend a strip of material that forms a channel for the glass blocks to be installed into, which is placed on all four sides of the panel.
-
-
3
Check to make sure the frame is level on all sides.
-
4
Prepare the mortar as per the instructions on the bag so that it is thick enough to stick to the glass block when it is turned 90 degrees. Mix enough to last for about an hour of work. Do not place mortar on the sides of the glass block that fit into the channel.
-
5
Place a glass block into the bottom channel strip and slide it into the channel on the right side. Slide another into the channel on the left side.
-
6
Spread 1/2 to 3/8 inch of mortar on one side of another glass block and place it into the channel with the mortar against the glass block on the side. Set a spacer in place between the blocks at the top. Continue placing blocks with mortar on one side and spacers between them to finish the first row. Spread mortar on two opposite sides for the last block in the row and slide it into place between the outside block and the rest of the row.
-
7
Place a modified spacer on top of the blocks at either end of the row as per the manufacturer's instructions. Use the level to check and make sure the blocks are straight vertically and horizontally.
-
8
Spread mortar along the top of the row 1/2 to 3/8-inch thick. Make sure the spacers are not covered with mortar so that the glass blocks fit on them correctly.
-
9
Use the foam brush to smooth and clean the mortar seams on both sides of the panel, pushing mortar to fill any holes.
-
10
Repeat steps 5 through 9 until the panel is complete. Cut the channel for the top in half lengthwise so it can be slid into place from either side. Do not place spacers along the top of the top row.
-
11
Let the mortar set for about an hour, then break the outer tabs off the spacers as per the manufacturer's instructions. Before the mortar dries completely, wipe the glass blocks down with a damp sponge to remove any excess. It is very difficult to remove mortar after it dries.
-
12
Use the striking tool and run it along all the horizontal seams, then all the vertical seams, creating a firm, smooth, concave seam, and filling in any holes.
-
13
Apply the glass block sealant between the glass blocks and the channel, and between the channel and the frame in wet areas, such as a shower surround. Use it to seal the top channel to the frame as well.
-
14
Use decorative molding to finish the framing if desired.
-
1
Tips & Warnings
These instructions are for interior panels less than 25 feet square with framing on all four sides and no curves. The materials and instructions differ slightly for larger panels or panels framed on three sides only. For panels larger than 25 feet square, steel rods are used between each layer vertically and horizontally to strengthen the glass block wall.
References
Resources
- Photo Credit glass block image by Sunshine Photos from Fotolia.com
