How to Seal Flagstone Floors

What You'll Need
Soft bristled broom and dustpan and brush/hard floor approved vacuum cleaner
Neutral detergent
Mop and Bucket
Acid-Free Stone Sealant (water based is best for interior jobs)
Large paint roller and tray

Flagstone floors offer a great design feature to homeowners seeking an organic feel to their interiors. While flagstone floors are generally durable and hard-wearing, over  time the floors natural finish can become dull and colors muted with wear. One way to prevent a loss of lustre is to seal flagstone floors to help protect them from the perils of footfall. Sealed floors will repel spills and stains and require little maintenance meaning that sealing floors when they are laid will save care time in the long run.

Step One - Clear and Prepare Your Flagstone Floor

Pick a day when you are able to keep family and pets away from the area that is to be treated. As drying will take some time and multiple coats may be needed it can be advisable to carry out this task at a time when the home is empty. To start with, you will need to move all furnishings and and throw rugs off of the flagstone floor area. Once this is done you should collect any dust or debris sitting on the surface of the floor using a soft bristle broom and dustpan and brush or a vacuum cleaner that is approved for use on hard floors - using an unapproved vacuum cleaner can damage the surface of the floor. One loose dirt is removed mop the floor using a solution of neutral detergent and water to remove stubborn grime, paying particular attention to high traffic areas. Allow the floor to dry thoroughly.

Step Two - Apply Stone Sealant to Flagstone Floor

Using a paintbrush, apply stone sealant all around the edges of your flagstone floor, in the same way you would "cut in" before beginning to paint a wall using a roller. Once this task is completed pour the stone sealant into a clean paint tray and apply to the rest of the surface of the floor using a clean paint roller. If the paint roller is new you may wish to wash it first to avoid the loss of fibers which can lodge in the stone sealant and ruin the finish of the floor. Start at the point furthest from the area's exit in order to avoid the possibilty of becoming trapped and needing to walk over the already sealed areas. Allow to dry.

Step Three - Apply Additional Coats of Stone Sealant

A minimum of two coats of stone sealant should be applied to all flagstone floors. For areas of your home where flagstone floors see a heavy footfall you may wish to consider adding a third coat. Subsequent coats should be applied in the same way as the first, with each coat being allowed to dry thoroughly between applications. For best protection, flagstone floors should be resealed every two years following the same instructions.