1. What is GLEAN Slurry Primer?
GLEAN Slurry Primer is a high-performance bonding primer designed to prepare and stabilise surfaces before applying cement-based coatings, waterproofing systems, renders, or repair mortars. Its slurry formulation creates a strong mechanical bond between the substrate and the subsequent coating layer, improving adhesion and durability.
2. What is a slurry primer used for?
A slurry primer acts as a bonding bridge between the substrate and the coating applied on top. It improves adhesion and reduces the risk of delamination or failure when applying materials such as:
• Cementitious waterproof coatings
• Floor screeds
• Render systems
• Repair mortars
• Tanking systems
• Self-levelling compounds
3. What surfaces can GLEAN Slurry Primer be applied to?
GLEAN Slurry Primer is suitable for use on many mineral and masonry surfaces, including:
• Concrete
• Cement render
• Brick and blockwork
• Stone
• Screeds
• Cementitious boards
• Rough masonry surfaces
It is ideal for preparing porous or slightly uneven substrates before applying a protective or finishing layer.
4. Can it be used on damp surfaces?
Yes.
GLEAN Slurry Primer can typically be applied to damp but not waterlogged surfaces. This makes it particularly useful for applications involving tanking systems, waterproofing coatings, and basement treatments.
However, standing water should be removed before application.
5. Do I need to prepare the surface before applying the primer?
Yes. Proper preparation is essential for optimal adhesion.
Before applying the primer:
• Remove loose debris, dust, grease, oils, and contaminants.
• Remove flaking coatings or unstable material.
• Lightly dampen highly absorbent surfaces.
• Ensure the substrate is structurally sound and clean.
Mechanical cleaning such as brushing, grinding, or pressure washing may be required depending on the condition of the surface.
6. How is GLEAN Slurry Primer applied?
Step 1 – Surface Preparation
Ensure the substrate is clean, sound, and free from contaminants. Remove any loose material, dust, grease, or previous coatings.
Step 2 – Mixing
Mix the slurry primer thoroughly according to the product instructions until a smooth, lump-free consistency is achieved.
Step 3 – Application
Apply the primer using:
• A stiff brush
• Masonry brush
• Roller
• Trowel (depending on the substrate)
Work the slurry well into the surface to ensure maximum penetration and adhesion.
Step 4 – Coverage
Apply a uniform coat across the surface. Avoid overly thick applications.
Step 5 – Drying Time
Allow the primer to become tacky or partially cured before applying the next coating layer.
7. When should the next coating be applied?
The subsequent coating (such as waterproofing slurry or render) should normally be applied when the primer is still slightly tacky but not wet.
This ensures the best possible chemical and mechanical bond between layers.
Always follow the specific curing times recommended in the product instructions.
8. What is the coverage rate?
Coverage will vary depending on the porosity and texture of the substrate.
Typical coverage is approximately:
4–6 m² per litre or 3–5 m² per kg
Highly porous surfaces may require additional primer.
9. Can GLEAN Slurry Primer be used indoors and outdoors?
Yes.
It is suitable for both interior and exterior applications, including:
• Walls and floors
• Basement waterproofing systems
• Structural concrete preparation
• Render preparation
• Wet rooms and bathrooms
• Water tanks and reservoirs (when used within approved systems)
10. Is it suitable for waterproofing systems?
Yes.
GLEAN Slurry Primer is commonly used as a key primer for cementitious waterproofing coatings and tanking systems, helping them bond securely to the substrate and improving long-term performance.
11. Can it be used on smooth concrete?
Yes, but smooth concrete should be mechanically roughened (e.g., by grinding or sandblasting) to improve adhesion before applying the primer.
12. What temperature should it be applied in?
For best results, apply when ambient and surface temperatures are between:
• 5°C and 30°C
Avoid application in:
• Freezing conditions
• Direct intense sunlight
• Extremely hot or windy conditions
These can affect curing and bonding performance.
13. How long does it take to dry?
Drying time depends on temperature, humidity, and substrate absorbency.
Typical conditions:
• Initial set: 1–3 hours
• Ready for overcoating: 2–6 hours
Always check that the primer is tacky or appropriately cured before applying the next layer.
14. Can it be used on painted surfaces?
No.
GLEAN Slurry Primer must be applied to bare, sound mineral substrates. Any existing paint, sealers, or coatings should be removed before application.
15. Is it suitable for floors as well as walls?
Yes.
It can be used to prepare both horizontal and vertical surfaces, including floors prior to applying screeds, repair mortars, or waterproof coatings.
16. Can it improve adhesion of repair mortars?
Yes.
Applying GLEAN Slurry Primer before repair mortars or cementitious coatings significantly improves bonding strength and helps prevent separation or cracking.
17. How should unused product be stored?
Store in a cool, dry location away from direct sunlight and frost. Ensure containers are tightly sealed after use to prevent contamination or premature curing.
18. Is GLEAN Slurry Primer suitable for professional and DIY use?
Yes.
It is suitable for both professional contractors and experienced DIY users, particularly for projects involving waterproofing, rendering, or structural repairs.
19. What are typical applications?
GLEAN Slurry Primer is commonly used for:
• Basement waterproofing preparation
• Tanking systems
• Preparing concrete before screeding
• Preparing masonry before rendering
• Structural repair works
• Preparing surfaces for cementitious coatings
• Damp-proofing systems
20. Why should I use a slurry primer instead of a standard primer?
Unlike standard primers, slurry primers:
• Bond chemically with cement-based materials
• Create a strong mechanical key
• Work effectively on porous mineral surfaces
• Improve durability and adhesion of heavy coatings
This makes them ideal for construction and waterproofing systems.
