Exterior 450 Topcoat a clear-drying finish suitable for vertical exterior surfaces, such as fences, patio furniture, garage doors, entrance doors and interior windows. It is not recommended as a deck finish. Exterior 450 is fortified with UV absorbers to stabilize the finish and built-in properties to protect it outdoors. It performs well as a clear coat or as an optional topcoat over General Finishes Milk Paint.
Specifications
| Type | Urethane/Acrylic Blend |
|---|---|
| Base | Water |
| Interior / exterior | Exterior |
| Sheens | Flat (10 or less), Satin (25-35), Semi-Gloss (50-60), Gloss (80+) |
| Color | Water White in can (dries clear) |
| Ambers (yellows) | No |
| Apply with | Brush, Roll, Spray |
| Spray tip | HVLP 1.1mm-1.3mm |
| Coats | 2 - 3 coats |
| Dry to touch | 30+ minutes |
| Recoat after | 2+ hours |
| Light use after | 7-10 days |
| Full cure | 21 days |
| Coverage | 140-160 sq ft/quart, 560-640 sq ft/gallon |
| Durability | High |
| Over an existing finish | Yes |
| Tintable | Yes |
| VOC | Flat: <125 g/L Satin: <125 g/L Semi-Gloss: <125 g/L Gloss: <125 g/L |
Questions & answers
How soon can my project go outside?
Wait 5-6 days. The finish keeps hardening for about 20-21 days.
Can I use it on a deck?
No. It is not meant for large horizontal surfaces such as decks. General Finishes Outdoor Oil can be used on decks.
How long will it last outdoors?
Typically 3-5 years, depending on conditions. It contains UV protection for the film (not the wood) and mildewcides. No exterior finish lasts forever; plan on maintenance and recoating.
Can it go over a stain mixed with mineral spirits?
No. Water-based finishes like Exterior 450 do not work over mineral spirits, even after a long dry time, and the finish can peel. If that happens, there is no fix short of sanding down and starting over.
How do I apply it, and how long between coats?
Brush, roll or spray, 2-3 coats. Dry to the touch in 30+ minutes, ready to recoat after 2+ hours. It does not amber; it dries clear.
Specifications from General Finishes.