GW 3-2

Single Component Solvented Coating Application

BASE COATS

1. After the tape installation, including coating where required, apply base coat in the specified coverage. Stir all coatings before use. All specified quantities are minimum and are on an undiluted basis. The number of coats is not usually specified and will depend on the slope, drying conditions and other job conditions. Single component solvented coatings produce a better film with less entrapped air when the rate of application is one gallon per square (4.1 L /10 m²) (16 mils (.4mm) wet). This is the recommended rate. The specified gallonage and uniformity of application are critical elements.
2. Apply coatings in a uniform thickness without skips or holidays. Hand or pressure roller coaters, depending on the job size, are best for this application. Neoprene coatings do not spray easily. However, other coatings may be sprayed. Allow each coat to dry until tack free and dry enough for foot traffic without damage before applying additional coatings. Several hours to overnight will be required, the time depending on drying conditions.
3. Extend each coat over cants and up vertical surfaces of pads, curbs, walls and parapets. The top of curbs and equipment pads shall be similarly coated. In the case of walls and parapets, extend coating to the point where counterflashing enters the masonry. Where no counterflashing is specified, hold the base coats just short of the termination line at edge of deck to avoid seeping under masking tape or spilling on adjacent unprotected surfaces.
4. If the entire job cannot be carried through to completion without interruption, the interruption should occur after the first base coat. This will provide protection for the tape system and general area.
   Before resuming work, the surface must be well cleaned by washing with solvent-alkaline cleaner or liquid detergent. This cleaning is necessary to remove dirt accumulation and the surface film that forms on exposed neoprene or polyolefin. Failure to remove either can result in poor adhesion. In hot, sunny conditions, surface films can form on neoprene in as little as two days. Under such conditions it is best to schedule application to avoid interruptions. If they must occur, cleaning is essential to assure adhesion. GacoFlex U-68 Ure-Cap and U-6006 Ure-Shield must be primed with U-5677, E-2465 or E-5481 if more than 72 hours have elapsed between coats.
   Remove oil or grease by solvent wiping. Solvent wiping must be done lightly and with extreme care to avoid lifting or wrinkling.

TOP COATS

1. Top coats should be applied the next day, if possible, after the final base coat. This will enhance adhesion. Note that the preferred time to interrupt a job, if necessary, is after the first base coat (See 1.5), not between the base coat and the top coat.
2. Inspect the roof for damage prior to the application of the top coat. Any damage must be repaired by re-flashing, re-taping and replacing of base coat so that a continuous membrane in a substantially uniform thickness covers the entire surface prior to the application of the top coat.  Important: Stir all pigmented materials thoroughly before use.
3. Apply top coat over base coat in the specified coverage. Specified quantities are minimum and on an undiluted basis. The normal rate of application per coat is 3/4 to 1 gallon per 100 square feet (2.8 L to 4.1 L /10 m²) (12 to 16 mils (.3 mm to .4 mm) wet) for Hypalon® or polyolefin which may be applied by roller, brush or spray. Roller application is recommended where possible over neoprene base coats - especially where there may be wind. Use new rollers or roller previously used only in the same coating and cleaned in fresh solvent. The normal rate of application per coat of Ure-Cap and Ure-Shield is 3/4 to 1-½ gallon per 100 square feet (2.8 L to 6.1 L / 10 m²) (12 to 24 mils (.3 mm to .6 mm) wet). They may be applied with brush, roller or spray. New rollers should be used since it is not economically practical to clean them and the old ones will cure and become unusable.
4. While careful color matching procedures are used in the Gaco Western plant, different batches may vary slightly in hue. This variation will be too slight to be perceptible if changes are made at natural breaks in the surface. Some intermixing of batches may be necessary if changes cannot be made at natural breaks.
5. Since the solvents used in top coat material coatings are similar to those used in neoprene base coatings, the first top coat may pick up some of the color from the base coating (this generally does not occur with U-68 Ure-Cap and U-6006 Ure-Shield). This is not objectionable, indicating a good bond of the two materials. The final top coat covers the discolored first coat completely. In good drying weather, no more than 24 hours should elapse between coats.
6. Remove masking tape at edges of coating area as soon as final coat is applied. By removing tape while coating is wet, you avoid damaging the edge of the coating by cutting the tape off. Any seepage under tape on rough surfaces can be wiped off with thinner while wet. .