Exterior Hardwearing Undercoat


0.75L, 2.5L

Coverage (per litre)

12 m²

Dry Time

16-24 Hours

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Product Details

Johnstone’s Exterior Hardwearing Undercoat is designed to be used with Johnstone’s Exterior Hardwearing Gloss. It provides a durable and long lasting finish for exterior wood and metal. It retains flexibility for longer and is resistant to blistering, cracking & peeling. For an optimum 6 year life use with Johnstone’s Exterior Hardwearing Gloss.  


  • Weather protection
  • Crack and peel resistance
  • 6 Year Life
All surfaces should be clean, dry and free from grease. Remove any loose or flaking paint. Rub down sound glossy surfaces with fine waterproof abrasive paper and rinse thoroughly to provide a key. Avoid the inhalation of dust. Wear a suitable face mask if dry sanding. Treat new or bare wood surfaces with a clear preservative, prime metal surfaces with an appropriate Johnstone’s metal primer. Special precautions should be taken during surface preparation of pre-1960s paint surfaces over wood and metal as they may contain harmful lead.
Ensure maximum ventilation during application and drying. Stir well before use and apply by brush or roller. For best results do not apply too thickly. Over primed bare wood and metal apply one coat of Johnstone’s Exterior Hardwearing Undercoat followed by two coats Johnstone’s Exterior Hardwearing Gloss. Plastic rainwater products should be cleaned thoroughly and given two coats of Johnstone’s Exterior Hardwearing Gloss. Under normal conditions allow 16-24 hours before applying a second coat if required. For maximum performance Johnstone’s Exterior Hardwearing Undercoat and Gloss should be applied as a system to pre-treated bare surfaces. Do not apply when air or surface temperature is below 10 C or in damp conditions.
Replace lid firmly after use. Remove as much product as possible from application equipment before cleaning. Clean all equipment immediately after use in White Spirit or Turpentine Substitute.
To avoid the risk of spillage, always store and transport in a secure upright position. Do not empty waste paint into drains or watercourses. Some local authorities have special facilities for the disposal of waste coatings.