Showing all 4 results
10 Year Guarantee.
Expert Support.
Sustainable Solutions.
Primers
& Admixes.
Stick With Success: Primers & Admixes That Bond like magic.
The foundation of every successful tiling project lies in proper preparation. Our range of specialist primers and additives ensures optimal adhesion, prevents chemical reactions between incompatible materials, and enhances the performance of adhesives and grouts.
Priming FAQs
Explore our Product FAQs to find quick answers to common questions about Dunlop priming and additive products, including application guidelines and best practices for achieving optimal results.
Q: Why is priming necessary before tiling or applying floor levellers?
Priming has several important functions:
- Improves adhesion between the substrate and the tile adhesive or levelling compound
- Reduces the absorbency of the substrate, preventing moisture from being drawn out of the adhesive too quickly
- Provides a barrier between chemically incompatible materials
- Prevents the formation of air bubbles in levelling compounds
- Extends the working life of adhesives on porous surfaces
- Helps achieve a stronger, more reliable bond
Skipping the primer step can lead to weak bonds, cracking and costly failures. The small investment in primer can prevent significant problems and callbacks later.
Q: Which Dunlop primer should I use for different surfaces?
For plaster walls when using cement-based adhesives:
- Dunlop Multi-Purpose Primer (2 coats undiluted)
- OR Dunlop SBR Universal Bonding Agent (diluted 1:2 with water)
For plaster walls when using ready-mixed adhesives:
- Dunlop Multi-Purpose Primer (diluted 1:1 with water, 1 coat only)
- OR Dunlop SBR Universal Bonding Agent (diluted 1:4 with water)
For cement/sand screeds and rendering:
- Dunlop Multi-Purpose Primer (diluted 1:1 with water)
- OR Dunlop SBR Universal Bonding Agent (diluted 1:4 with water)
For anhydrite/calcium sulphate screeds:
- Dunlop Multi-Purpose Primer (1st coat diluted 1:1, 2nd coat undiluted)
For tongue and groove floorboards:
- Dunlop Multi-Purpose Primer (2 coats undiluted)
- OR Dunlop SBR Universal Bonding Agent (diluted 1:2 with water, 2 coats)
Overlaid timber floors:
- Dunlop Multi-Purpose Primer (undiluted)
- OR Dunlop SBR Universal Bonding Agent (undiluted)
For fibre-reinforced cement boards & tile backer boards:
- Dunlop Multi-Purpose Primer (diluted 1:1 with water)
- OR Dunlop SBR Universal Bonding Agent (diluted 1:4 with water)
Q: Can I use PVA as a primer before tiling?
No, Dunlop strongly advises against the use of PVA (polyvinyl acetate) as a primer for tile projects. Despite what you may hear elsewhere, PVA is not suitable for tiling applications because:
- PVA can re-emulsify when it comes into contact with moisture from the tile adhesive.
- When cement-based adhesives come into contact with PVA, acetic acid is formed which weakens the bond.
- PVA forms a film rather than penetrating the substrate, which can lead to bond failure.
- Unlike proper tile primers, PVA does not prevent chemical reactions between substrates and cement-based adhesives.
Always use a tile primer such as Dunlop Multi-Purpose Primer or Dunlop SBR Universal Bonding Agent, which are specifically formulated for tile applications.
Q: What is Dunlop Flexible Additive and when should I use it?
Dunlop Flexible Additive is a high-quality water based polymer emulsion designed to improve the performance of cement based adhesives and grouts. Use it to:
- To improve flexibility: When tiling areas subject to slight movement or vibration
- To increase bond strength: When tiling on difficult substrates such as existing tiles or glazed surfaces
- To improve water resistance: In wet areas such as showers or swimming pools
- For outdoor applications: To improve the durability of outdoor tiling projects
- With porcelain tiles: To improve bond strength with these dense, low-absorption tiles
For tile adhesives, typically mix 1 part Dunlop Flexible Additive to 1 part water for CX and CF series adhesives, or 1 part Flexible Additive to 3 parts water for CS1 series adhesives.
For grouts, use 1 part Flexible Additive to 2 parts water, or 1:1 for more demanding applications.
Q: What is Dunlop Temporary Tile Sealer and when should I use it?
Dunlop Temporary Tile Sealer is a protective product designed to be applied to tile surfaces prior to grouting. It’s particularly useful for:
- Textured or porous tiles: Prevents grout from staining these surfaces
- Natural stone: Protects porous stone from grout staining or discoloration
- Unglazed ceramic or quarry tiles: Creates a barrier against grout penetration
How to use:
- Apply undiluted sealer with a clean cloth to tile surfaces (avoiding the joints)
- Allow to dry for at least 15 minutes before applying a second coat if needed
- Allow to dry fully before commencing grouting
- The sealer is temporary and will wash away during the clean-up process
Q: How much primer do I need for my project?
Coverage depends on the specific primer and the porosity of the substrate:
Dunlop Multi-Purpose Primer:
1kg undiluted covers approx. 10m², but may be less on very porous substrates.
Dunlop SBR Universal Bonding Agent:
- As a primer/sealer (diluted 1:4): Approximately 40m² per 5kg unit
- As a slurry coat mixed with cement: Approximately 3m² per kg
Always allow extra for particularly porous surfaces or for multiple coats.
Q: Do I need to prime before self-levelling?
Yes, priming before applying self-levelling compounds is essential:
- On porous surfaces (concrete, screeds):
- Apply Dunlop Multi-Purpose Primer diluted 1:1 with water
- OR Dunlop SBR Universal Bonding Agent diluted 1:4 with water
- On non-porous surfaces (existing tiles, vinyl):
- Apply undiluted Dunlop Multi-Purpose Primer
- OR neat Dunlop SBR Universal Bonding Agent
- For anhydrite screeds:
- Apply Dunlop Multi-Purpose Primer (first coat diluted 1:1, second coat neat)
Priming helps prevent air bubbles from forming in the leveller, improves adhesion, and prevents moisture loss from the levelling compound.
Q: How soon can I tile after priming?
Waiting times depend on the primer and substrate:
Dunlop Multi-Purpose Primer:
- Allow approximately 30-60 minutes until touch dry before tiling
- Second coats (if applied) may require similar drying times
Dunlop SBR Universal Bonding Agent:
- Allow to dry completely (typically 1-2 hours depending on conditions)
- Must be completely dry and slightly tacky before applying adhesive
Environmental conditions such as temperature, humidity, and ventilation will affect drying times.
Q: What preparation is needed before priming?
Before applying any Dunlop primer:
- Clean thoroughly: Remove all dust, dirt, grease and loose material.
- Fix any surface problems: Fill cracks or holes and allow repairs to dry
- Remove old coverings: Make sure any wallpaper, paint or old glue is removed
- Check for flatness: Surface should be reasonably flat and level
- Allow new surfaces to cure: New plaster (4 weeks), new screed (3 weeks), concrete (6 weeks)
- Sand glossy surfaces: For glossy or polished surfaces, lightly abrade to create a key.
The success of your tiling project depends largely on thorough surface preparation prior to priming.
Q: What common mistakes should I avoid when priming?
- Using PVA instead of a proper tiling primer: PVA is not suitable for tiling.
- Skipping the primer: this vital step ensures longevity and proper adhesion.
- Not allowing the primer to dry properly: If you rush this stage, you risk a poor bond
- Applying too thick: Primer should penetrate the substrate, not form a film
- Using the wrong dilution: Follow product specific instructions
- Forgetting the second coat: If necessary, a second coat is essential
- Do not apply the second coat at 90° to the first: This ensures complete coverage
- Allow the primer to form puddles: Maintain an even application
For technical assistance on any Dunlop primer product, please contact the Dunlop Technical Helpline on 01782 591120.
Top Tip
“When applying a primer to calcium sulphate (anhydrite) screeds, many tilers make the costly mistake of applying it too thinly. These highly absorbent screeds need special attention – for the first coat, dilute Multi-Purpose Primer 1:1 with water to help it penetrate, but the second coat must be applied neat and at 90° to the first for complete protection. If you see the blue colour disappearing too quickly into the substrate, it’s a warning sign that it’s too absorbent and may need an additional coat.
Remember, the time you spend on proper priming is your insurance policy against the dreaded ‘ettringite formation’ – the chemical reaction between cement and gypsum that ruins tile work months later. A few extra minutes of proper priming can save days of expensive remediation!”
David Hilton – Technical Support Manager
keep in touch.
Join our mailing list for all the latest product and industry news.