New plaster and concrete need sealing before emulsion or texture. Short answer: National PVA Primer Sealer for Masonry is a clear, water-based PVA sealer that National says adheres well to cementitious surfaces. One coat covers about 10 to 15 m² per litre, is touch dry in an hour and can be recoated in 2 to 3 hours. It appears as a primer option in National’s emulsion, eggshell, Graffio and textured-finish systems.
Key facts
| Type | Water-based PVA primer sealer |
| Surfaces | Interior and exterior concrete, plaster and brickwork (the sheet also lists asbestos) |
| Finish and colour | Smooth, clear |
| Volume solids | 30 ± 2% |
| Spreading rate | 10 to 15 m² per litre (theoretical) |
| Film per coat | 20 to 30 microns dry (65 to 100 wet) |
| Drying at 30°C | Touch dry 1 hour; recoat after 2 to 3 hours |
| Application | Brush or roller |
| Thinning | 10 to 15% with water, depending on the surface |
| Shelf life | 18 months, sealed |
Where National uses it
- Eggshell Silky system: Primer Sealer, Stucco Filler, then two coats of Eggshell Silky.
- Textured-finish system: Primer Sealer or Acrylic Primer, Tex Primer, then a Tex finish.
- Graffio Decor: one of three primer options.
PVA Primer Sealer vs PVA Primer White
| PVA Primer Sealer | PVA Primer White | |
|---|---|---|
| Colour | Clear | White |
| Volume solids | 30 ± 2% | 35 ± 2% |
| Spreading rate | 10 to 15 m²/L | 10 to 11.5 m²/L |
| Application | Brush or roller | Brush, roller or spray |
| Main role per National | Sealer for cementitious surfaces | Primer for texture spray systems |
How much to buy
One coat on 50 m² needs about 3.3 to 5 litres, and on 100 m² about 6.7 to 10 litres, by our calculation. Porous surfaces use more.
Frequently asked questions
How is it different from Penetrating Sealer?
Both are water-based sealers. See our Penetrating Sealer guide for a side-by-side.
Step 1: prepare the surface
- National’s surface preparation guide asks for a clean, dry, sound surface. Exteriors are washed with high-pressure water (2200 psi minimum) and left to dry.
- Remove laitance and efflorescence, and brush off loose material.
- Fill cracks with Joint Filler once the sealer has dried, or as the topcoat system lists.
What the numbers mean
Coverage = volume solids × 10 ÷ dry film: 30 × 10 ÷ 20 = 15 and 30 × 10 ÷ 30 = 10 m² per litre. That is the sheet’s range. Its low solids are what let it soak into the surface; very absorbent plaster will sit near the lower figure.
| Area, one coat | Litres (10 to 15 m²/L) |
|---|---|
| 45 m² (bedroom walls) | about 3 to 4.5 L |
| 200 m² (two-bed flat) | about 13.3 to 20 L |
| 400 m² (villa exterior) | about 27 to 40 L |
Mistakes to avoid
- Using it where a white primer is specified. Shield textures and Synplast name Acrylic Primer (W.B.).
- Spraying it. The sheet lists brush or roller.
- Topcoating early. Wait 2 to 3 hours at 30°C.
Which other products list it?
National names it as a primer option under Plastic, Nice, Diffatex and Super Finetex, among others. Compare all emulsions in National emulsions compared.
Buy in Sharjah and Dubai
Shop National Acrylic Primer 18 L, or message us on WhatsApp for PVA Primer Sealer.
Sources
- National PVA Primer Sealer data sheet (PDF, via AEC Online)
- National PVA Primer White data sheet (PDF, via AEC Online)
- National Paints surface preparation guide, Sec. A-2 (PDF)
Retrieved 3 November 2026. Quantities are our own calculations. The main image is illustrative.
