This is a clear exterior finish for use on wood, fiberglass, coated metal or painted surfaces and contains ultraviolet absorbers for advanced sun protection.  Available in Satin, Semi-Gloss and Gloss sheens.

Technical Data Sheet

Where to Use
Exterior Water-Based Spar-Urethane is recommended for use on exterior wood, fiberglass, coated metal or painted surfaces. It can be used on unfinished wood surfaces or previously finished surfaces. This finish can also be used over stained surfaces that have thoroughly dried. Allow oil-based stain to dry a minimum of 24 hours.

Ideal for use on exterior wood surfaces such as outdoor furniture, fencing and gables, as well as wood, fiberglass and steel doors. For interior use on windowsills and door frames for added Ultra Violet protection. (DO NOT USE on wooden decks or steps, wood siding, log homes or wood boats below water-line.)

As with all exterior clear finishes, this product will not offer unlimited protection against the elements. Surfaces which receive direct sunlight may have to be re-coated annually to maintain gloss and to prevent cracking and peeling.

Surface Preparation
All surfaces must be clean, dry and free from dirt, wax, grease, glue and other contaminants or penetration and adhesion will be affected. DO NOT use over shellac, lacquer, filler, stains or sealers containing stearates. After sanding, remove sanding dust with vacuum or damp cloth. DO NOT use a tack rag to remove dust, as it may leave a residue that will interfere with adhesion.

Bare Wood: Sand surface thoroughly with medium grit sandpaper and progress to fine grit sandpaper.
Always sand in the direction of the wood grain. Do not use steel wool.

Previously Finished Surfaces: Surface should be sanded to remove imperfections and gloss, using extra fine sandpaper (220 grit), sanding with the grain. Do not use steel wool.

Stained Surfaces: Stain must be thoroughly dry before applying clear finish. Allow oil-based stain to dry a minimum of 24 hours in good drying conditions before top coating. Do not sand uncoated stained surface.

Stir thoroughly before and during application. DO NOT SHAKE. Test the finish on an inconspicuous area to ensure adequate adhesion. Exterior Water-Based Spar-Urethane appears milky in the can but dries clear. Do not apply in direct sunlight or areas of extreme air movement.

  • Apply with a synthetic fiber brush, foam brush, flat pad or sprayer. A short nap roller may be used for large flat areas but must be brushed immediately to alleviate air bubbles.
  • Apply in full, even coats in the direction of the grain. Do not over apply. Over applying can produce a milky appearance.
  • Do not over brush or create excess air bubbles.
  • Spar-Urethane will dry to touch in 30 minutes and ready to topcoat after 1 hour. Sand lightly between coats with fine sandpaper to produce a finer finish. If sandpaper gums up allow more dry time. Remove sanding dust. Allow 1 to 2 hours before recoating.
  • Reapply. Three coats are recommended for minimum protection. Additional coats are recommended for wood, fiberglass and steel exposed to direct sunlight.

Do not use on decks or areas that are subject to foot traffic.

Please note: Testing is very important when applying this product over paints or stains because the appearance of these products may change when a water-based finish is applied. This product gives a soft wood amber that ONLY becomes noticeable when applied over white or pastel paints and stains.

Thinning is not recommended, but if necessary, a small amount of water may be added. For spray applications, up to one (1) pint of water per gallon may be used.

Approximately 230 to 470 square feet per gallon. Coverage will vary significantly depending on application method and condition of wood.

Drying Time
Apply when air and surface temperatures are between 60° and 90°F and humidity is between 30% and 70%. At 50% relative humidity and 70°F, Exterior Water-Based Spar-Urethane will dry to touch within 30 minutes and ready to topcoat after 1 hour. Dry time will be affected by temperature, humidity and film thickness. Protect product from freezing prior to and during application.

Wait 24 hours before subjecting surfaces to light use. Care should be used during the first week after application as the finish is still curing to its ultimate hardness.

Wash brushes and equipment in warm, soapy water. Rinse clean.

MAX VOC: 275 grams/liter (2.29 lbs/gal)

Why use clear finishes?

Clear finishes are used to seal and protect surfaces. In many cases, clear finishes offer lasting, durable protection from abrasion, marring, and chipping. Most clear finishes also protect the surfaces from damage caused by water and alcohol. Exterior clear finishes provide protection to withstand water, weather, and sunlight.

Suggested Supplies

  • Fine grade sandpaper or nylon sanding pad
  • Tack cloth
  • Stir stick
  • Drop cloth
  • Quality, China bristle brush
  • Mineral spirits or paint thinner
  • Rubber gloves
Product Number Sheen Size Safety Data Sheets
74401 Gloss Gallon EnglishSpanishFrench
74404 Gloss Quart EnglishSpanishFrench
74405 Gloss 5 Gallon EnglishSpanishFrench
74501 Satin Gallon EnglishSpanishFrench
74504 Satin Quart EnglishSpanishFrench
74505 Satin 5 Gallon EnglishSpanishFrench
74601 Semi-Gloss Gallon EnglishSpanishFrench
74604 Semi-Gloss Quart EnglishSpanishFrench
74605 Semi-Gloss 5 Gallon EnglishSpanishFrench