Janitorial & Sanitation Reference Library · Technical Reference

Floor Sealers

Floor sealers fill and protect porous floors so finish or traffic does not soak in or stain them. This sheet sorts water-based, penetrating and sealer-finish products by floor type and explains where each fits in a floor care program.

Ref JS-0114ASTM D2047

Draft, open for review. Check every value against the governing standard and the manufacturer’s data before use.

What it is

A floor sealer is a base coat for porous surfaces such as concrete, terrazzo, stone, some quarry tile and older worn resilient floors. It fills the surface so later coats of finish go on evenly and stain-causing liquids stay on top. Water-based acrylic sealers form a film like a floor finish but are built for adhesion and filling. Penetrating sealers soak into concrete or stone and react or fill inside the pores, leaving little or no surface film. Some penetrating products are densifiers that harden concrete. Sealer-finishes are one product used as both, mainly on light-traffic floors.

How to use it

Identify the floor and confirm with the floor maker's care guide.
Strip or clean to a bare, dry, residue-free surface.
Do a test patch for adhesion and appearance, especially on stone.
Apply thin, even coats with a clean applicator. Let each coat dry fully.
Follow with finish if the program calls for it. Check that the finish is compatible with the sealer.

Sealer types

Type	How it works	Typical floors	Notes
Water-based acrylic sealer	Surface film that fills pores	Concrete, terrazzo, porous resilient floors	Usually topped with finish; strippable
Penetrating sealer (stone or concrete)	Soaks in and fills pores	Natural stone, grout, concrete	Little shine; repels stains
Concrete densifier	Reacts with concrete to harden the surface	Warehouse and retail concrete	Often part of a polished concrete process
Sealer-finish	One product for base and wear coats	Light-traffic areas	Lower durability than separate coats
Solvent-based sealer	Film in a solvent carrier	Some concrete and garage floors	Ventilation and flammability; check local VOC rules

Key points

Terrazzo and natural stone can be damaged by harsh acids and high-alkaline strippers. Use products labeled for them.
New vinyl composition tile often has a factory coating. Follow the tile maker's guidance before sealing or finishing.
Penetrating sealers are generally not stripped. Plan for that before using them.
Slip resistance claims are often tested with ASTM D2047. The result depends on the full coating system and maintenance.
Read the SDS for ventilation and storage, especially for solvent products.

Common mistakes

Sealing over a damp or dirty floor so the sealer peels.
Using an acrylic film sealer on a floor meant for a penetrating sealer.
Applying heavy coats that stay soft.
Using acidic cleaners on sealed marble or terrazzo.

Governing standards: ASTM D2047 (static coefficient of friction of polish-coated floor surfaces). Floor maker care guides and product technical data sheets.

Reference only. Verify against the current governing code or standard, the manufacturer's data and the project documents before use. Apps for Distributors disclaims liability arising from reliance on this reference.

More in Technical Reference

← All Janitorial & Sanitation sheets