Adhesives and Sealants — FAQ
What's the difference between polyurethane and solvent-based construction adhesives?
Polyurethane adhesives (like Loctite PL Premium) bond to damp surfaces, cure through moisture, and remain flexible. Solvent-based adhesives dry by evaporation, work only on dry surfaces, and become rigid. Polyurethane offers superior strength and versatility.
Can I paint over construction adhesive?
Most heavy-duty construction adhesives are paintable once fully cured. Polyurethane formulas accept latex and oil-based paints without bleeding. Always verify the product label and test a small area first, as some solvent-based adhesives may discolor paint.
How long does heavy duty construction adhesive take to cure?
Tack-free time ranges from 20-60 minutes. Handling strength develops in 4-24 hours depending on temperature and humidity. Full cure reaches maximum strength in 24-72 hours. Polyurethane adhesives cure faster in humid conditions.
Can I use construction adhesive on wet or frozen surfaces?
Polyurethane adhesives bond to damp surfaces and even cure underwater. Solvent-based adhesives require completely dry surfaces—moisture prevents proper curing. For frozen materials, thaw first or use specialized cold-weather formulas rated below 40°F.
What's the shelf life of unopened construction adhesive?
Most cartridges last 12-18 months unopened when stored at 60-80°F. Squeeze tubes have similar shelf lives. Polyurethane adhesives may skin over in the tube after opening. Always check expiration dates and store tubes upright to prevent leakage.
Do I need a caulk gun for cartridge adhesives?
Yes, 9-10 ounce cartridges require a standard caulk gun for proper dispensing. Ratchet-style guns provide better control than basic friction guns. For small projects, consider squeeze tubes that require no additional tools and offer greater portability.