How to Finish Sandstone
- 1). Sweep or vacuum the sandstone to remove as much of the dust debris as you can. Wash the stone with soapy water so it is clean and dust-free for finishing. Be sure the stone is completely dry before applying the sealant.
- 2). Pour the sealant into an empty tray -- a litter tray, paint tray or plastic tub are all suitable. Use a roller, paint pad or lamb's wool applicator to apply the sealant.
- 3). Dip the applicator into the sealant. Apply the sealant to the sandstone starting in a corner. Use big brush strokes to cover the whole area working outward from the corner. Apply a generous coating of sealant, since the stone is porous and will soak it up. Carefully work across the whole surface then allow it dry thoroughly overnight.
- 4). Apply at least three more coats of sealant one at time. Allow each coat to dry before you apply the next one.
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