The method for repairing a glass block shower wall depends upon the material between the joints. Older glass block shower walls use mortar, while newer versions use plastic spacers. Follow these steps to easily repair a damaged glass block shower wall.
Step 1 - Determine the Extent of Damage
Glass blocks are themselves rarely damaged; it is usually the mortar. Since the mortar is exposed to high levels of moisture, it lose its water sealant coating over time and cracks. If the crack is small, it can be easily repaired with mortar mix. If there is a lot of damage, it can be re-grouted. For glass blocks that use plastic spacers, you must reapply silicone.
Step 2 - Repairing Minor Cracks
Clean the surface of the cracked mortar to remove any loose debris. Mix a small amount of mortar. Apply a sufficient amount of mortar to the crack and smooth it with a trowel. Allow the mortar to dry for 20 minutes before wiping the excess with a damp sponge. Once the mortar has dried completely, apply sealant. As soon as the sealant dries, the shower is ready to use.
Step 3 - Repairing Major Damage
For major damage, the best options is to re-grout the joints. That does not mean removing all of the grout. It only involves removing the top surface of the grout to provide space for the new grout.
Use a grout saw to level the grout. Wash the grout with water and mix the sanded grout powder.
Scoop the mix into the rubber float. Apply the grout to the scraped joints in several strokes in a single direction. Continue until every joint is nicely grouted. Wait 20 minutes before wiping the excess grout away with a damp sponge. Allow the grout to dry for about 48 hours. Apply sealant and allow it to dry before using the shower.
Step 4 - Resealing Glass Blocks
If the glass blocks are spaced with plastic spacers instead of mortar, the silicone may become loose after long periods of use. In order to repair the glass block shower wall, simply allow the shower to dry and prepare it for resealing. Remove any loose silicone beads. Then apply beads of silicone into the spacers and smooth them with your finger. Allow the silicone to cure completely before using the shower.