Varathane Ultimate Spar Urethane – Water-Based Exterior Coating, Semi-Gloss

Crystal-clear exterior protection for wood

Varathane Ultimate Water-Based Spar Urethane provides a crystal-clear shield for exterior wood, helping maintain natural grain while standing up to sun, rain, and seasonal changes. The low-odor, water-based formula cleans up easily with soap and water, making outdoor projects feel more manageable and less disruptive.

Real-world uses

• Protect exterior doors and window trim while preserving natural wood color
• Refresh fences, decks, rails, and outdoor furniture with durable, weather-ready protection
• Finish outdoor accents and architectural details for a refined, long-lasting look
• Touch up exposed beams or siding where UV exposure is a concern
• Apply to exterior surfaces on appliances or features that endure the elements

Key benefits

• Durable polyurethane designed for outdoor wood surfaces such as doors, windows, fences, trim, and more
• Low odor and easy cleanup with soap and water thanks to a water-based formula
• Dries to the touch in about 30 minutes and covers up to 87 sq ft per quart; recoat after 2 hours
• Weather- and UV-resistant finish that stays crystal clear and does not yellow
• Semi-gloss finish delivers a smooth, refined look on exposed wood

Application tips for best results

• For maximum protection on outdoor projects, apply a minimum of four coats of non-yellowing poly
• Prepare surfaces, apply evenly, and allow about 2 hours between coats in good ventilation
• Clean tools with soap and water after use; allow surfaces to dry fully before exposure to the elements
• Ensure proper surface cleaning and light sanding between coats for a smoother finish

Varathane’s exterior spar urethane offers practical, crystal-clear protection that helps outdoor wood projects look fresh longer. While results depend on factors like pre-treatment and weather, this coating provides a reliable, aesthetically pleasing finish that enhances natural grain without appearing cloudy or yellow over time.