Overview

Achieve the ultimate exterior finish with Sandtex 10 Year Exterior Primer Undercoat this is a high-performance primer designed to prepare and protect a wide range of outdoor surfaces. When used as part of the 2-step system with Sandtex 10 Year Exterior Multi-Surface Gloss, this advanced water-based undercoat helps deliver up to 10 years of durable protection.

Specially formulated for flexibility and adhesion, this primer undercoat resists cracking, flaking and peeling, while its mould-resistant properties keep surfaces looking fresh and clean. Ideal for use on wood, weathered PVC-u, brick, stone, concrete, aluminium, and non-ferrous metals, it ensures a strong, lasting bond for your topcoat.

• 10 Year Protection 
• Ideal for wood, masonry, PVC-u, metal and more
• Designed to be used with Sandtex 10 Year Exterior Multi-Surface Gloss

Preparation

• Clean the Surface: Ensure all surfaces are clean, dry, and free from dirt, grease, and surface contaminants.
• Remove Loose Material: Scrape off any loose, flaking, or peeling paint.
• Sand the Surface: Thoroughly abrade previously painted wood and metal surfaces to provide suitable adhesion.
• Repair Defects: Fill any cracks or gaps with a suitable exterior filler and allow to dry.
• Treat Mould or Organic Growth: If present, treat the area with Sandtex Fungicidal Wash to remove mould and reduce staining.

Application

We always recommend performing a test patch to the surface to be decorated to ensure you are happy with the finished results.

• Stir Thoroughly: Before use, stir the primer thoroughly to ensure even consistency.
• Apply by Brush: Use a good quality paintbrush to apply the primer evenly, avoiding overspreading.
• Number of Coats: Typically, one coat is sufficient.
• Drying Time: Touch dry in 4–6 hours.
• Recoat after 16 hours.