Westcoat SC-65 Water-Based Polyurethane Concrete Sealer
About
The water-based polyurethane concrete sealer with traditional urethane performance, indoors or out
Stained concrete, ground floors, epoxy coatings, and decorative overlays all need a clear finish coat to protect them from wear, spills, and sunlight. The right sealer keeps that finish looking good whether the floor is inside a showroom or out around a pool.
Westcoat SC-65 is a two-component, high-solids, water-based polyurethane with properties equal to traditional urethanes, including easy cleaning, gloss retention, and abrasion resistance. It's UV, mar, and chemical resistant and won't yellow, so it performs on interior floors and on exterior surfaces exposed to the sun. SC-65 is available in Gloss, Semi-Gloss, and Flat. The Flat sheen goes over an epoxy or urethane coat, never directly on bare concrete.
Indoors, SC-65 is used in medium to heavy traffic areas such as hospitals, schools, hotels, and restaurants, and it's the standard sealer in Westcoat Grind & Seal systems for showrooms, retail stores, and offices. Outdoors, it seals Westcoat 11-10 and Texture-Crete systems on pool decks, patios, walkways, and driveways.
Material
Estimator
How many square feet is your project?
NOTE: Coverages shown are based on an average coverage of 300 square feet per gallon per coat.
Specs
Why Choose Westcoat SC-65?
- Suited to interior and exterior surfaces
- UV resistant and non-yellowing
- Holds up to chemicals, abrasion, and marring
- Clear finish coat over concrete, epoxy, and cementitious coatings
Westcoat Systems Using SC-65
SC-65 is the clear finish coat across Westcoat concrete coating, epoxy, decorative texture, and waterproofing systems. Semi-Gloss is the standard sealer in the Grind & Seal systems, Flat finishes the Tidalstone and Texture-Crete Interior floors, and all three sheens are listed as sealer options in several other systems. Wherever Flat is used, it goes over a sealed or coated surface, never bare concrete.
Concrete Coating Systems
- Grind & Seal, Fast Stain Grind & Seal, Nano Stain Grind & Seal, and Water-Based Stain Grind & Seal | Standard Sealer in Semi-Gloss over the ground or stained concrete, with Gloss or Flat as alternatives; Flat goes only over a sealed surface
- 11-10 Custom Finish | Sealer in Semi-Gloss over the SC-35 Water-Based Stain
- 11-10 Standard Finish | Alternative Topcoat in any sheen, used in place of the SC-10 Acrylic Topcoat
Epoxy Floor Coating Systems
- Tidalstone Thin Film and Tidalstone High Build | Flat Polyurethane Sealer over the EC-102 Pigmented Polyaspartic Topcoats, with Gloss or Semi-Gloss as alternatives
- Water-Based Thin Film | Optional Sealer in any sheen, applied over the EC-11 Water-Based Epoxy within 24 hours
Decorative Texture Systems
- Texture-Crete Interior | Flat Polyurethane Sealer over the EC-36 100% Solids Epoxy sealer coat, with Gloss or Semi-Gloss as alternatives over the EC-36
- Texture-Crete Broom-On | Alternative Sealer in any sheen, used in place of SC-42 WB Acrylic Sealer
- Texture-Crete Custom Finish and Texture-Crete Wood Finish | Alternative Sealer in any sheen, used in place of SC-70 Acrylic Lacquer Sealer
Waterproofing Systems
- ALX Waterproofing Underlayment and ALX Pro Waterproofing Underlayment | Two coats of Semi-Gloss over the dried slurry coat when the system is installed beneath a pedestal paver system
Product Specifications for Westcoat SC-65
| SPECIFICATION | DETAILS |
|---|---|
| Product Type | Two-Component, Water-Based Clear Polyurethane Sealer |
| Gloss Sheen | Greater Than 80 @ 60° |
| Semi-Gloss Sheen | 45–55 @ 60° |
| Flat Sheen | Less Than 10 @ 60° |
| Flat Sheen Substrate | Apply Over Epoxy or Urethane Only, Never Directly Over Concrete |
| Gloss Variation | Depends on Dry Film Thickness and Substrate Type |
| Recommended Uses | Finish Coat Over Concrete, Epoxies, and Cementitious Coatings |
| Solids Content | 65% by Volume, 66% by Weight |
| VOC Content | Less Than 50 g/L |
| Mix Ratio | 3:1 (Part A to Part B) by Volume |
| Pot Life | 1–1.5 Hours (150 g @ 72°F) |
| Coverage, Smooth Surfaces | 400–650 Sq Ft per Gallon* |
| Coverage, Textured Surfaces | 200–400 Sq Ft per Gallon* |
| Application | Airless Spray (Recommended), Roll, Broom, or Squeegee and Back Roll |
| Recoat Time | 4–8 Hours, Within 24 Hours** |
| Light Foot Traffic | 12 Hours** |
| Normal Traffic | 24 Hours** |
| Vehicle Traffic | 72 Hours** |
| Full Cure | 72 Hours (@ 6 Mil) |
| Water Exposure | After a Minimum 48-Hour Cure |
| Application Temperature | 50°F–80°F; Surface No Higher Than 80°F |
| Pencil Hardness | 2H |
| Adhesion on Concrete (ASTM D3359) | 5 (7-Day Cure) |
| Chemical Resistance (ASTM D1308) | Rated 5 (No Effect) Against Most Tested Chemicals, Including Gasoline, Brake Fluid, Bleach, and Xylene (2-Hour Contact) |
| Cleanup | Water |
| Shelf Life | 1 Year in Unopened Packaging |
| Packaging | 1 Gallon Kit, 20 Gallon Kit |
| Certifications | VOC Emission Test Certificate, Berkeley Analytical No. 180531-02; USDA and FDA Compliant |
*Coverage rates are approximate and vary with surface texture and porosity, application method, and the desired finish. Refer to the current Technical Data Sheet for complete application and coverage information.
**Times are based on an average temperature of 70°F and 50% humidity. Hot or cold weather may affect dry times.
How-To
Application Instruction Overview for Westcoat SC-65
IMPORTANT! Before You Begin: Review the complete SC-65 Water-Based Polyurethane Concrete Sealer Technical Data Sheet (TDS) and Safety Data Sheet (SDS), linked above, before installation. When SC-65 is part of a Westcoat system, also follow that system's specification. The information below is a brief overview and does not replace the manufacturer's complete application instructions.
Step 1 – Inspect and Prepare the Surface
- The surface must be structurally sound, dry, and free of oil, grease, paint, curing agents, laitance, dirt, dust, and anything else that could prevent adhesion
- Prepare concrete to a minimum CSP 2 surface profile per ICRI; the surface must be porous or rough enough for the sealer to soak in
- Test concrete for moisture and contact Westcoat before applying if emissions exceed 5 lbs/1,000 sq ft (ASTM F1869) or relative humidity exceeds 75% (ASTM F2170)
- Over ALX, MACoat, or Texture-Crete systems, apply directly over the textured surface; clean it first if the texture has sat for more than 24 hours or has become dirty
- Over textured epoxy systems, apply within 24 hours; after 24 hours, lightly abrade the surface and wipe it with a solvent such as denatured alcohol
- Do not apply the Flat sheen directly over concrete; apply it over an epoxy or urethane such as EC-11 Water-Based Epoxy or EC-32 on interior jobs, and over SC-65 Gloss or Semi-Gloss on exterior jobs
Step 2 – Mix the Material
- Premix Part A and Part B separately
- In a clean bucket, combine 3 parts A with 1 part B by volume
- Mix with a low-speed (200–300 rpm) drill for 2–3 minutes, scraping the sides and bottom of the container; avoid mixing by hand
- Pot life is 1–1.5 hours (150 g @ 72°F)
- Thin only when using SC-65 as a primer over concrete or applying it with a Chapin or pump-style sprayer; Gloss or Semi-Gloss may be thinned up to 30% with water
- Do not thin over smooth, non-porous surfaces; thinning may affect gloss, sheen, and overall appearance
Step 3 – Apply the Sealer
- Apply immediately after mixing; for best results, spray SC-65 neat with an airless sprayer
- Smooth surfaces: apply with a squeegee and back roll with a ¼" to ⅜" high-quality, non-shedding roller cover, keeping a wet edge, or dip and roll
- Textured surfaces: spray evenly and promptly back roll with a ⅜" to ½" non-shedding roller cover or a decorative concrete broom, or dip and roll
- As a primer over a textured surface, apply thin and let it soak into the substrate so the water can evaporate
- Apply two thin, even coats; do not over roll, overwork, or let the material puddle
Step 4 – Recoat and Cure
- Recoat once the surface is dry to the touch, in about 4–8 hours, and within 24 hours to ensure adhesion
- If more than 24 hours pass, lightly sand the surface and wipe it with a solvent such as denatured alcohol just before recoating
- Allow light foot traffic after 12 hours, normal traffic after 24 hours, and vehicle traffic after 72 hours (at 70°F and 50% humidity)
- Cure for a minimum of 48 hours before the surface comes in contact with water
- Clean equipment with water immediately after use
Installation Limitations
- For professional use only
- Do not apply below 50°F or above 80°F, or when the surface temperature is above 80°F
- Do not apply over damp surfaces
- Do not apply SC-65 Flat directly over concrete
- The surface will be more slippery once sealed; skid-resistant additives are available
- Do not allow the material to freeze
FAQs
Can SC-65 Flat be applied directly to concrete?
No. To avoid whitening, SC-65 Water-Based Flat Polyurethane Sealer goes over an epoxy or urethane, such as EC-11 Water-Based Epoxy or EC-36 100% Solids Epoxy on interior floors, or over SC-65 Gloss or Semi-Gloss on exterior surfaces. Gloss and Semi-Gloss can be applied over properly prepared concrete.
Which SC-65 sheen should I choose?
Gloss reads above 80 at 60 degrees for a high-shine, wet look, Semi-Gloss reads 45 to 55 for a noticeable but softer sheen, and Flat reads below 10 for a low-sheen, natural look, though actual gloss varies with film thickness and substrate. In Westcoat systems, Semi-Gloss is the standard sealer for Grind & Seal floors, and Flat gives Tidalstone floors their natural finish that resembles polished concrete or terrazzo and finishes Texture-Crete Interior floors.
Will SC-65 change the color of my concrete?
It can. SC-65 enhances color, which can bring out the tones in stained or decorative concrete. If you'd rather keep the color as close to unsealed as possible, apply a prime coat of EC-11 Clear Water-Based Epoxy first. Either way, test on a small area before sealing the whole floor.
Can SC-65 be used outdoors?
Yes. SC-65 is UV resistant and won't yellow, so it holds up in the sun on surfaces like pool decks. It's also used to seal 11-10 Custom Finish and Texture-Crete systems on patios, walkways, and driveways. If you want the Flat sheen outside, put down a coat of Gloss or Semi-Gloss first and apply the Flat over it.
How much SC-65 do I need?
Plan on roughly 400 to 650 square feet per gallon on smooth surfaces like epoxy coatings, and 200 to 400 square feet per gallon on textured surfaces like Texture-Crete or diamond-ground concrete. Two thin coats give the best results, so figure coverage for both.
How soon can I walk or drive on a floor sealed with SC-65?
Light foot traffic is allowed after 12 hours, normal traffic after 24 hours, and vehicle traffic after 72 hours at 70 degrees and 50% humidity. Allow at least 48 hours of cure before the surface contacts water.
How long should I wait between coats of SC-65?
Apply the second coat as soon as the first is dry to the touch, usually in about 4 to 8 hours, but no later than 24 hours. If you miss that window, lightly sand the surface and wipe it with a solvent such as denatured alcohol just before recoating. Those times are based on 70 degrees and 50% humidity, so expect the wait to run longer in cool weather and shorter in hot weather.
Can SC-65 be thinned?
Only when it's used as a primer over concrete or applied with a Chapin or pump-style sprayer. Gloss and Semi-Gloss can be thinned up to 30% with water, but thinning isn't recommended over smooth, non-porous surfaces and may affect the finished sheen.
Westcoat SC-65 Water-Based Polyurethane Concrete Sealer
Westcoat SC-65 is a two-component, water-based polyurethane concrete sealer used as the clear finish coat over concrete, epoxy, and cementitious coatings, available in Gloss, Semi-Gloss, and Flat sheens.
- Interior and Exterior Use | UV resistant and non-yellowing, so it keeps its clarity and gloss on sun-exposed surfaces as well as interior floors
- Chemical and Stain Resistant | Stands up to acids, solvents, automotive fluids, bleach, and food spills like red wine and ketchup
- Built for Traffic | Impact, abrasion, and mar resistance for medium to heavy traffic areas
- Quick Return to Service | Light foot traffic in 12 hours, normal traffic in 24 hours, and vehicles in 72 hours
- USDA and FDA Compliant | Used in restaurants, hospitals, and schools, with LEED credit points available
About
The water-based polyurethane concrete sealer with traditional urethane performance, indoors or out
Stained concrete, ground floors, epoxy coatings, and decorative overlays all need a clear finish coat to protect them from wear, spills, and sunlight. The right sealer keeps that finish looking good whether the floor is inside a showroom or out around a pool.
Westcoat SC-65 is a two-component, high-solids, water-based polyurethane with properties equal to traditional urethanes, including easy cleaning, gloss retention, and abrasion resistance. It's UV, mar, and chemical resistant and won't yellow, so it performs on interior floors and on exterior surfaces exposed to the sun. SC-65 is available in Gloss, Semi-Gloss, and Flat. The Flat sheen goes over an epoxy or urethane coat, never directly on bare concrete.
Indoors, SC-65 is used in medium to heavy traffic areas such as hospitals, schools, hotels, and restaurants, and it's the standard sealer in Westcoat Grind & Seal systems for showrooms, retail stores, and offices. Outdoors, it seals Westcoat 11-10 and Texture-Crete systems on pool decks, patios, walkways, and driveways.
Material Estimator
How many square feet is your project?
NOTE: Coverages shown are based on an average coverage of 300 square feet per gallon per coat.
Specs
Why Choose Westcoat SC-65?
- Suited to interior and exterior surfaces
- UV resistant and non-yellowing
- Holds up to chemicals, abrasion, and marring
- Clear finish coat over concrete, epoxy, and cementitious coatings
Westcoat Systems Using SC-65
SC-65 is the clear finish coat across Westcoat concrete coating, epoxy, decorative texture, and waterproofing systems. Semi-Gloss is the standard sealer in the Grind & Seal systems, Flat finishes the Tidalstone and Texture-Crete Interior floors, and all three sheens are listed as sealer options in several other systems. Wherever Flat is used, it goes over a sealed or coated surface, never bare concrete.
Concrete Coating Systems
- Grind & Seal, Fast Stain Grind & Seal, Nano Stain Grind & Seal, and Water-Based Stain Grind & Seal | Standard Sealer in Semi-Gloss over the ground or stained concrete, with Gloss or Flat as alternatives; Flat goes only over a sealed surface
- 11-10 Custom Finish | Sealer in Semi-Gloss over the SC-35 Water-Based Stain
- 11-10 Standard Finish | Alternative Topcoat in any sheen, used in place of the SC-10 Acrylic Topcoat
Epoxy Floor Coating Systems
- Tidalstone Thin Film and Tidalstone High Build | Flat Polyurethane Sealer over the EC-102 Pigmented Polyaspartic Topcoats, with Gloss or Semi-Gloss as alternatives
- Water-Based Thin Film | Optional Sealer in any sheen, applied over the EC-11 Water-Based Epoxy within 24 hours
Decorative Texture Systems
- Texture-Crete Interior | Flat Polyurethane Sealer over the EC-36 100% Solids Epoxy sealer coat, with Gloss or Semi-Gloss as alternatives over the EC-36
- Texture-Crete Broom-On | Alternative Sealer in any sheen, used in place of SC-42 WB Acrylic Sealer
- Texture-Crete Custom Finish and Texture-Crete Wood Finish | Alternative Sealer in any sheen, used in place of SC-70 Acrylic Lacquer Sealer
Waterproofing Systems
- ALX Waterproofing Underlayment and ALX Pro Waterproofing Underlayment | Two coats of Semi-Gloss over the dried slurry coat when the system is installed beneath a pedestal paver system
Product Specifications for Westcoat SC-65
| SPECIFICATION | DETAILS |
|---|---|
| Product Type | Two-Component, Water-Based Clear Polyurethane Sealer |
| Gloss Sheen | Greater Than 80 @ 60° |
| Semi-Gloss Sheen | 45–55 @ 60° |
| Flat Sheen | Less Than 10 @ 60° |
| Flat Sheen Substrate | Apply Over Epoxy or Urethane Only, Never Directly Over Concrete |
| Gloss Variation | Depends on Dry Film Thickness and Substrate Type |
| Recommended Uses | Finish Coat Over Concrete, Epoxies, and Cementitious Coatings |
| Solids Content | 65% by Volume, 66% by Weight |
| VOC Content | Less Than 50 g/L |
| Mix Ratio | 3:1 (Part A to Part B) by Volume |
| Pot Life | 1–1.5 Hours (150 g @ 72°F) |
| Coverage, Smooth Surfaces | 400–650 Sq Ft per Gallon* |
| Coverage, Textured Surfaces | 200–400 Sq Ft per Gallon* |
| Application | Airless Spray (Recommended), Roll, Broom, or Squeegee and Back Roll |
| Recoat Time | 4–8 Hours, Within 24 Hours** |
| Light Foot Traffic | 12 Hours** |
| Normal Traffic | 24 Hours** |
| Vehicle Traffic | 72 Hours** |
| Full Cure | 72 Hours (@ 6 Mil) |
| Water Exposure | After a Minimum 48-Hour Cure |
| Application Temperature | 50°F–80°F; Surface No Higher Than 80°F |
| Pencil Hardness | 2H |
| Adhesion on Concrete (ASTM D3359) | 5 (7-Day Cure) |
| Chemical Resistance (ASTM D1308) | Rated 5 (No Effect) Against Most Tested Chemicals, Including Gasoline, Brake Fluid, Bleach, and Xylene (2-Hour Contact) |
| Cleanup | Water |
| Shelf Life | 1 Year in Unopened Packaging |
| Packaging | 1 Gallon Kit, 20 Gallon Kit |
| Certifications | VOC Emission Test Certificate, Berkeley Analytical No. 180531-02; USDA and FDA Compliant |
*Coverage rates are approximate and vary with surface texture and porosity, application method, and the desired finish. Refer to the current Technical Data Sheet for complete application and coverage information.
**Times are based on an average temperature of 70°F and 50% humidity. Hot or cold weather may affect dry times.
How-To
Application Instruction Overview for Westcoat SC-65
IMPORTANT! Before You Begin: Review the complete SC-65 Water-Based Polyurethane Concrete Sealer Technical Data Sheet (TDS) and Safety Data Sheet (SDS), linked above, before installation. When SC-65 is part of a Westcoat system, also follow that system's specification. The information below is a brief overview and does not replace the manufacturer's complete application instructions.
Step 1 – Inspect and Prepare the Surface
- The surface must be structurally sound, dry, and free of oil, grease, paint, curing agents, laitance, dirt, dust, and anything else that could prevent adhesion
- Prepare concrete to a minimum CSP 2 surface profile per ICRI; the surface must be porous or rough enough for the sealer to soak in
- Test concrete for moisture and contact Westcoat before applying if emissions exceed 5 lbs/1,000 sq ft (ASTM F1869) or relative humidity exceeds 75% (ASTM F2170)
- Over ALX, MACoat, or Texture-Crete systems, apply directly over the textured surface; clean it first if the texture has sat for more than 24 hours or has become dirty
- Over textured epoxy systems, apply within 24 hours; after 24 hours, lightly abrade the surface and wipe it with a solvent such as denatured alcohol
- Do not apply the Flat sheen directly over concrete; apply it over an epoxy or urethane such as EC-11 Water-Based Epoxy or EC-32 on interior jobs, and over SC-65 Gloss or Semi-Gloss on exterior jobs
Step 2 – Mix the Material
- Premix Part A and Part B separately
- In a clean bucket, combine 3 parts A with 1 part B by volume
- Mix with a low-speed (200–300 rpm) drill for 2–3 minutes, scraping the sides and bottom of the container; avoid mixing by hand
- Pot life is 1–1.5 hours (150 g @ 72°F)
- Thin only when using SC-65 as a primer over concrete or applying it with a Chapin or pump-style sprayer; Gloss or Semi-Gloss may be thinned up to 30% with water
- Do not thin over smooth, non-porous surfaces; thinning may affect gloss, sheen, and overall appearance
Step 3 – Apply the Sealer
- Apply immediately after mixing; for best results, spray SC-65 neat with an airless sprayer
- Smooth surfaces: apply with a squeegee and back roll with a ¼" to ⅜" high-quality, non-shedding roller cover, keeping a wet edge, or dip and roll
- Textured surfaces: spray evenly and promptly back roll with a ⅜" to ½" non-shedding roller cover or a decorative concrete broom, or dip and roll
- As a primer over a textured surface, apply thin and let it soak into the substrate so the water can evaporate
- Apply two thin, even coats; do not over roll, overwork, or let the material puddle
Step 4 – Recoat and Cure
- Recoat once the surface is dry to the touch, in about 4–8 hours, and within 24 hours to ensure adhesion
- If more than 24 hours pass, lightly sand the surface and wipe it with a solvent such as denatured alcohol just before recoating
- Allow light foot traffic after 12 hours, normal traffic after 24 hours, and vehicle traffic after 72 hours (at 70°F and 50% humidity)
- Cure for a minimum of 48 hours before the surface comes in contact with water
- Clean equipment with water immediately after use
Installation Limitations
- For professional use only
- Do not apply below 50°F or above 80°F, or when the surface temperature is above 80°F
- Do not apply over damp surfaces
- Do not apply SC-65 Flat directly over concrete
- The surface will be more slippery once sealed; skid-resistant additives are available
- Do not allow the material to freeze
FAQs
Can SC-65 Flat be applied directly to concrete?
No. To avoid whitening, SC-65 Water-Based Flat Polyurethane Sealer goes over an epoxy or urethane, such as EC-11 Water-Based Epoxy or EC-36 100% Solids Epoxy on interior floors, or over SC-65 Gloss or Semi-Gloss on exterior surfaces. Gloss and Semi-Gloss can be applied over properly prepared concrete.
Which SC-65 sheen should I choose?
Gloss reads above 80 at 60 degrees for a high-shine, wet look, Semi-Gloss reads 45 to 55 for a noticeable but softer sheen, and Flat reads below 10 for a low-sheen, natural look, though actual gloss varies with film thickness and substrate. In Westcoat systems, Semi-Gloss is the standard sealer for Grind & Seal floors, and Flat gives Tidalstone floors their natural finish that resembles polished concrete or terrazzo and finishes Texture-Crete Interior floors.
Will SC-65 change the color of my concrete?
It can. SC-65 enhances color, which can bring out the tones in stained or decorative concrete. If you'd rather keep the color as close to unsealed as possible, apply a prime coat of EC-11 Clear Water-Based Epoxy first. Either way, test on a small area before sealing the whole floor.
Can SC-65 be used outdoors?
Yes. SC-65 is UV resistant and won't yellow, so it holds up in the sun on surfaces like pool decks. It's also used to seal 11-10 Custom Finish and Texture-Crete systems on patios, walkways, and driveways. If you want the Flat sheen outside, put down a coat of Gloss or Semi-Gloss first and apply the Flat over it.
How much SC-65 do I need?
Plan on roughly 400 to 650 square feet per gallon on smooth surfaces like epoxy coatings, and 200 to 400 square feet per gallon on textured surfaces like Texture-Crete or diamond-ground concrete. Two thin coats give the best results, so figure coverage for both.
How soon can I walk or drive on a floor sealed with SC-65?
Light foot traffic is allowed after 12 hours, normal traffic after 24 hours, and vehicle traffic after 72 hours at 70 degrees and 50% humidity. Allow at least 48 hours of cure before the surface contacts water.
How long should I wait between coats of SC-65?
Apply the second coat as soon as the first is dry to the touch, usually in about 4 to 8 hours, but no later than 24 hours. If you miss that window, lightly sand the surface and wipe it with a solvent such as denatured alcohol just before recoating. Those times are based on 70 degrees and 50% humidity, so expect the wait to run longer in cool weather and shorter in hot weather.
Can SC-65 be thinned?
Only when it's used as a primer over concrete or applied with a Chapin or pump-style sprayer. Gloss and Semi-Gloss can be thinned up to 30% with water, but thinning isn't recommended over smooth, non-porous surfaces and may affect the finished sheen.
