Using the wrong thinner can ruin a tin of paint. Short answer: National’s water-based emulsions and primers thin with clean water. Acrylic Rock Top Coat and Road Marking take National Acrylic Thinner. Aluminium Paint uses National G.P. Thinner, and the two-pack Nationalthane topcoat uses National Polyurethane Thinner. The table below lists each product’s thinning range, taken from its National Paints data sheet.
Thinner and thinning by product
| Product | Thinning (by volume) | Thinner / cleaner |
|---|---|---|
| Matt Emulsion | 5 to 10%, depending on method | Water |
| Eggshell Emulsion Matt | 5 to 10%, depending on method | Water |
| Acrylic Primer (water-based) | 10 to 15%, depending on method | Water |
| PVA Primer White for Masonry | 10 to 15%, depending on method | Water |
| Stucco Filler | Ready for use | Water (for cleaning) |
| Acrylic Rock Top Coat | 5 to 15%, depending on method | National Acrylic Thinner |
| Acrylic Road Marking | 5% | National Acrylic Thinner |
| Aluminium Paint | Ready for use | National G.P. Thinner (for cleaning) |
| Nationalthane Topcoat | 5 to 15%, depending on method | National Polyurethane Thinner |
Data sheets
Tips for thinning
- Thin less for brush and roller, more for spray. National’s sheets give a range “depending on the method of application”; spraying normally sits at the top of it.
- Never mix systems. Do not add water to a solvent-based paint, or acrylic thinner to an emulsion.
- Two-pack products: for Nationalthane, mix base and hardener 4:1 by volume first, then thin. Its pot life is 8 hours at 30°C.
- Use the same thinner for cleaning brushes, rollers and spray guns.
Frequently asked questions
Can I use a general-purpose thinner in Acrylic Rock?
National specifies its Acrylic Thinner for Acrylic Rock Top Coat. Stick to the thinner named on the data sheet; we cannot vouch for substitutes.
Does aluminium paint need thinning?
Its data sheet says it is ready for use, with National G.P. Thinner named as the thinner and cleaner.
Buy National Paints thinners in Sharjah and Dubai
Shop National Acrylic Thinner 3.6 L, or message us on WhatsApp for G.P. or Polyurethane Thinner.
Sources
- National Paints technical data sheets via AEC Online: Matt Emulsion, Eggshell Matt, Acrylic Primer, PVA Primer White, Stucco Filler, Acrylic Rock Top Coat, Road Marking, Aluminium Paint, Nationalthane Topcoat
Retrieved 3 November 2026. The main image is illustrative.
