If you would like to try a glass block window installation in your home, here are four tips to help.
Step 1 - Place Bottom Shims
You should start by measuring your window and the opening to ensure the window will fit. Position 1/2-inch shims along the bottom level of the window to keep the window raised off the sill.
Step 2 - Fill the Bottom Space with Mortar
Into the space between the windowsill and the block window's bottom surface, pack enough mortar that the weight of the window will depress the mortar to no more than 1/2 inch of thickness.
Step 3 - Fill Side Spaces with Mortar
Position shims in the window's side spaces between the sill and glass, so that spaces on both sides are equal. Fill the spaces with mortar, then remove the side shims, clean off excess mortar, and allow the applied mortar to dry for 24 hours.
Step 4 - Caulk the Top Space
After the mortar dries, you can continue with your glass block window installation. Into the top space, place a foam backer rod and fill the gaps with caulk. When it dries, remove the bottom shims and fill those spaces with caulk.