This product is for exterior use only. Stain Blocking Primer is a white, water-based hybrid primer that penetrates deeply and is eco-friendly with low VOC.

It minimizes tannin bleed-through from wood onto exterior boards. With cedar or pine, for example, a pale finish can become stained over time by the resin present in these wood species.

This product contains resins that protect against the elements, reducing water damage and ultraviolet light degradation. After at least 24 hours of drying, we recommend topcoating with an opaque finish stain. For example, Sansin ENS stain in opaque on vertical surfaces or opaque Steina (Storm Stain) for deck floors.

Sansin Stain Blocking Primer is a penetrating, 1-coat, environmentally friendly coating specially designed for patios, decks, and fences. This primer is ideal for cedar, pine, spruce, fir, and treated wood. This product is UV-resistant and water-repellent. The modified natural oil in Sansin penetrates deep into the wood, regardless of its moisture content (which often exceeds 25% for decks).

This product will not crack, peel, or blister. It’s the ideal choice for maintaining the beauty and natural integrity of your wood, without yellow tannin bleed-through showing through your opaque stain.

• Water-repellent protective coating against tannin bleed-through and UV rays
• High-performance, eco-friendly water-based hybrid technology (low VOC)
• Highly penetrating primer, even on damp wood (moisture content above 25%)
• Repels water but does not prevent moisture evaporation
• Molecular compatibility creates a monolithic bond with the wood for long-lasting protection (fuses with the wood)
• White primer that can be topcoated with an opaque stain or paint

Preparation:

• Ensure the surface is free of any defects or deterioration. Replace defective parts if necessary
• The surface must be clean and free of all dust, dirt, grease, wax, and/or old coating
• Wash the surface with the appropriate Sansin cleaner and/or stripper using a high-pressure washer.
• Allow to dry at least 4 hours
• Sand the wood using a belt or orbital sander with 80-grit sandpaper

How to apply:

Stain Blocking Primer deck primer is easy to apply: simply saturate the surface by applying a generous coat (by brush or spray) and check to remove any puddles or runs with a brush. Then allow to penetrate and apply a coat of opaque finish stain the same way after at least 24 hours of drying. We recommend Sansin ENS stain in opaque on vertical surfaces or opaque Steina (Storm Stain) for deck floors.

Very important: do not apply during the hottest part of the day or in direct sunlight (do not apply if the wood is warm to the touch). Can be applied to wood with moisture content up to 25%. Can be applied to green wood. Do not apply on rainy days and/or during cold nights; the product requires 24 hours of drying after application. Take care to mix the product well before and during application so the color is uniform.

Maintenance:

Vertical surfaces require regular maintenance. Periodically wash your wood with Sansin multi-wash biodegradable cleaner to remove dust, dirt, and stains.
When the finish begins to look worn (discoloration or erosion), it is time to consider applying a maintenance coat. Normally, a maintenance coat will be required at a frequency ranging from 1 to 4 years. The maintenance frequency will depend on the quality of preparation, application, application conditions, and exposure to wear factors and weather. Maintaining your wood on a regular basis will allow it to keep its color long-term, have better dimensional stability, and maintain its water-repellent properties.

If discoloration or erosion is evident, wash your wood using a pressure washer and/or use Sansin Multi-Wash to remove dust and dirt. Then reapply a maintenance coat. Exposure, application, and color choice will affect the coating’s performance.