Extreme Clear Polyurethane Concrete Primer and Sealer 20.0 kg

Q: What surfaces can this product be used on?

It is ideal for porous concrete floors, cement slabs, screeds, cementitious toppings, and block paving before applying polyurethane topcoats. It is not recommended for asphalt, very dense screeds, or decorative stone that may darken.

Q: Can it be used as both a primer and a standalone sealer?

Yes, it works in two ways. As a primer it improves adhesion of PU floor paints, and as a standalone sealer two or more coats provide a satin, dust-resistant finish that protects against water and oil.

Q: Does it darken the surface when applied?

When used as a sealer it creates a clear satin film that slightly enhances the natural colour of the concrete without changing it dramatically. Always test a small area first if colour change is a concern.

Q: How many coats are recommended for best performance?

For priming, one coat is generally sufficient. As a sealer, apply at least two coats to achieve full dustproofing, stain resistance, and a more uniform satin finish.

Q: What is the typical coverage per litre?

Coverage is usually between 6–10 m² per litre per coat, depending on how porous the surface is. Rough or highly absorbent slabs may require extra material for complete sealing.

Q: How long does it take to dry before recoating?

At around 18 °C it is touch-dry in 4–6 hours and ready for a second coat after about 8 hours. Cooler conditions or high humidity will extend drying times.

Q: When can the surface be used after application?

Light foot traffic is possible after roughly 8 hours, but heavy traffic such as forklifts or vehicles should be avoided for at least 48 hours. Full chemical resistance develops after 7 days.

Q: Is it breathable once cured?

Yes, the cured film allows vapour to escape while blocking liquid water, helping to prevent moisture entrapment that can damage the substrate.

Q: How should the surface be prepared before application?

The concrete should be clean, dry, and free of dust, grease, and laitance. Any cracks or holes should be repaired, and highly polished or power-floated surfaces may need mechanical abrasion for better penetration.

Q: What is the best way to apply this product?

It can be applied using a roller, brush, or suitable sprayer. Use thin, even coats and avoid pooling to allow deep penetration into the substrate.

Manufactured by Extreme Paints

Why Choose Our Products?

Deep penetration stops concrete dust

Excellent base for PU floor paints

Cuts delamination on heavy films

Hard‑wearing clear satin protection

Touch dry in four to six hours

Extreme Paints Clear Polyurethane Concrete Primer & Floor Sealer is a single-pack, low-viscosity polyurethane designed to penetrate deep into porous concrete, binding loose dust particles and strengthening the substrate. As a primer, it promotes exceptional inter-coat adhesion for PU floor paints, significantly reducing the risk of delamination even under heavy-duty use such as forklifts, pallet trucks, and high foot traffic.

When used as a standalone sealer, it provides a satin, protective finish that highlights the natural colour of the concrete while repelling oil, water, and common household chemicals. Its breathable properties allow vapour transmission while preventing liquid ingress, ensuring long-term performance without trapping moisture.

Manufactured in the UK under ISO 9001 standards, each batch is quality-checked for viscosity, penetration, and cure time, guaranteeing consistent professional results for both trade and DIY applications.

Suitable Substrates

Porous concrete floors and screeds
Cement slabs and flags
Cementitious toppings
Block paving and masonry (before applying PU topcoats)

Not recommended for asphalt, dense non-porous screeds, or decorative stone where darkening may occur.

Uses & Benefits

Primer use: Promotes adhesion of PU topcoats and prevents peeling
Sealer use: Two coats provide a dust-free, stain-resistant satin finish
Heavy-duty resistance: Withstands vehicle traffic, oils, and cleaning agents
Professional-grade: Low-viscosity resin ensures deep penetration and substrate binding
Durable protection: Enhances surface life and reduces maintenance costs

Coverage & Spread Rate

6–10 m² per litre, per coat, depending on substrate porosity.
Highly porous slabs will require more material for full coverage.

Drying & Curing Times (@ 18 °C)

Touch dry: 4–6 hours
Recoat window: 8 hours
Light foot traffic: 8 hours
Heavy traffic: 48 hours
Full chemical resistance: 7 days

Finish & Appearance

Clear satin film when applied as a sealer (two or more coats)
Invisible primer layer when overcoated with PU floor paints

Storage & Clean-Up

Store sealed between 5–30 °C, upright and away from ignition sources
Clean tools and rollers with white spirit or PU thinner before curing
Do not thin in excess of 5% to avoid weakening the film build.

Safety Disclaimer

This is a solvent-based, flammable coating. Apply in a well-ventilated space, keep away from naked flames, sparks, or high heat. Avoid inhaling vapours or prolonged skin contact; wear gloves, safety goggles, and a respirator mask if spraying. Keep out of reach of children. Dispose of waste in accordance with local regulations.

Packaging & Batch Notes

To ensure consistent results, order the full quantity in one batch. During periods of high demand, the product may arrive in plain tins with correct labels; this does not affect quality or performance.

Prepare Surface
Remove all dust, dirt, oil, algae, and flaking coatings to create a clean and sound substrate. Power-floated or very smooth concrete should be acid-etched or mechanically abraded to open the surface pores for proper penetration.

Mixing
Stir the product thoroughly with a paddle mixer for at least 2 minutes to ensure an even consistency before use. Decant into a paint tray or sprayer immediately after mixing.

Primer Use
Apply a single thin, even coat at approximately 50 µm wet film thickness using a roller, brush, or airless sprayer. Avoid pooling and ensure full coverage to achieve strong adhesion for subsequent polyurethane floor coatings.

Standalone Sealer
When used as a sealer, apply two thin coats to create a clear, satin protective film. Allow 4–6 hours between coats for proper drying. A third coat may be added if a higher sheen or enhanced protection is required.

CuringAllow light foot traffic after 8 hours and heavy vehicle or equipment traffic after 48 hours. Full chemical and stain resistance develops after 7 days, providing maximum durability and long-term performance.

Property	Value
Components	1-part single pack
Base	Polyurethane resin
Finish	Clear satin
Recommended coats	1 (primer) or 2 (sealer)
Wet film thickness	50 µm per coat
Coverage	6–10 m² per L per coat
Touch dry	4–6 h @ 18 °C
Recoat window	4–6 h
Full cure	7 days

Property	Value
Application tools	Brush, roller, HVLP, airless, pump sprayer
Clean-up	White spirit / PU thinner
Shelf life	24 months unopened
Pack sizes	5 L, 10 L, 20 L
Colour options	Clear
Interior / exterior	Both
Suitable substrates	Concrete, cement, stone, porous masonry
VOC	< 420 g /L
Primer required	Yes – on bare or rusty steel

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Frequently Asked Questions

What surfaces can this product be used on?

It is ideal for porous concrete floors, cement slabs, screeds, cementitious toppings, and block paving before applying polyurethane topcoats. It is not recommended for asphalt, very dense screeds, or decorative stone that may darken.

Can it be used as both a primer and a standalone sealer?

Yes, it works in two ways. As a primer it improves adhesion of PU floor paints, and as a standalone sealer two or more coats provide a satin, dust-resistant finish that protects against water and oil.

Does it darken the surface when applied?

When used as a sealer it creates a clear satin film that slightly enhances the natural colour of the concrete without changing it dramatically. Always test a small area first if colour change is a concern.

How many coats are recommended for best performance?

For priming, one coat is generally sufficient. As a sealer, apply at least two coats to achieve full dustproofing, stain resistance, and a more uniform satin finish.

What is the typical coverage per litre?

Coverage is usually between 6–10 m² per litre per coat, depending on how porous the surface is. Rough or highly absorbent slabs may require extra material for complete sealing.

How long does it take to dry before recoating?

At around 18 °C it is touch-dry in 4–6 hours and ready for a second coat after about 8 hours. Cooler conditions or high humidity will extend drying times.

When can the surface be used after application?

Light foot traffic is possible after roughly 8 hours, but heavy traffic such as forklifts or vehicles should be avoided for at least 48 hours. Full chemical resistance develops after 7 days.

Is it breathable once cured?

Yes, the cured film allows vapour to escape while blocking liquid water, helping to prevent moisture entrapment that can damage the substrate.

How should the surface be prepared before application?

The concrete should be clean, dry, and free of dust, grease, and laitance. Any cracks or holes should be repaired, and highly polished or power-floated surfaces may need mechanical abrasion for better penetration.

What is the best way to apply this product?

It can be applied using a roller, brush, or suitable sprayer. Use thin, even coats and avoid pooling to allow deep penetration into the substrate.

Can it be cleaned up easily?

Tools and rollers should be cleaned immediately with white spirit or PU thinner before the coating cures. Once cured, the product is very difficult to remove.

Is it safe to use indoors?

It can be applied indoors but requires excellent ventilation because it is solvent-based and flammable. Always wear gloves, eye protection, and a respirator mask if spraying.

Does it resist oil and chemical spills?

Yes, once fully cured the sealer resists water, light oils, and common household chemicals, helping to protect the floor from staining and wear.

Can it be used on freshly laid concrete?

The concrete must be fully cured and dry, typically at least 28 days old, before application to ensure proper adhesion and performance.

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