How to Seal Limestone Bricks

What You'll Need
Sealant suitable for limestone
Foam paint roller and brush
Paint tray
Scrubbing brush
Stone cleaner
Dustpan and brush
Rubber or latex gloves
Ventilation mask

With the installation of limestone bricks, you will be able to create a stylish look for your deck or pathway. Limestone is a natural substance and is one of the softer rocks, which means that it has a porous quality. In order to keep it blemish free and easy to maintain, it is necessary to complete some steps to seal the limestone.

Step 1 – Clean

The first step necessary is to prepare the limestone bricks that are being treated by cleaning it after clearing it of all furnishings. Thoroughly sweep the area, making sure that you pay careful attention to corners and edges to ensure that you gather up all the debris. During this process, it is prudent to inspect the floor to determine whether it comprises any deeper staining or defects that need to be repaired. If it is possible, avoid the use of water for cleaning, as this can react with a silicone based sealant. If water is necessary to help remove stains, such as with a stone cleaner, allow it to dry thoroughly before proceeding.      

Step 2 – Repair

Complete any repairs necessary to the limestone bricks prior to applying any sealant. This may involve removing and replacing a cracked brick, or topping up the grout where it may have come loose. In the event that new grout is applied to secure the bricks, it must be left for at least 12 hours to ensure that it dries.         

Step 3 – Prepare

If working indoors, make sure the area is well ventilated, as the sealant will often create powerful fumes. Protect yourself with the use of gloves and a face mask. When working in an enclosed area, ensure that you plan the manner in which the sealant will be applied so that you will not disturb your work when you leave the room.

Step 4 – Apply Sealant

Pour some of the sealant into a paint tray to give you better access to it. Gently roll the roller in the tray to coat the foam and apply it to the limestone bricks in long strokes to cover as much of the surface as possible. When working at the perimeters, keep the roller as close to the edge as possible and keep a foam brush to hand to complete awkward areas easily. Continue in this manner until the entire surface is covered.

Leave the sealant to settle on the limestone bricks for 5 minutes before using a circular rubbing motion to remove the excess. This will have the effect of dulling the sheen of the wet-look on the surface. Following this, leave the sealant to dry for at least 3 hours before applying a second coat of the sealant in the same way as the first. Sealant requires reapplication and should be applied more regularly in wet conditions. When drops of water no longer pool on the surface, but are absorbed, it is time to apply another coat of sealant.