Window Door & Siding Polyurethane Sealant

Available Sizes: 10 fl. oz.


Color When Dry: Redwood Tan, Bronze, White, Gray



Where to Buy


Loctite® PL® Window Door & Siding Polyurethane Sealant

Safety Precautions

Gloves. Sealant may temporarily stain skin.


Surface Preparation:
Surfaces must be structurally sound, dry, clean, free of dirt, moisture, loose particles, oil, grease, asphalt, tar, paint, wax, rust, waterproofing, curing and painting and compound.

Concrete, stone, stucco and other masonry must be cleaned where necessary by grinding or wire brushing to expose a sound surface free of contamination. Concrete must be fully cured.

Wood and painted wood:
Cut back weathered and treated surfaces and dry rot until clean, sound wood is reached. Loctite® PL® S40 Polyurethane Window, Door & Siding Sealant will adhere to most new and old dry, oil-free wood. Scrape away paint to bare wood.

Scale, rust and coatings must be removed to expose bright metal. Protective coatings should be removed with a solvent as well as any chemical residue or film. For example aluminum window frames are often coated with a clear lacquer that must be removed before the application of Loctite® PL® S40 Polyurethane Window, Door & Siding Sealant.

General Preparation:
Use above 40°F (4°C). In cool or cold weather, store container where temperature is about 75°F (25°C) for at least 24 hours before using. Cut nozzle at a 45° angle to desired bead size and puncture inner seal.

While PL® S40 Polyurethane Window, Door & Siding Sealant is generally considered a non-priming sealant, special circumstances or substrates (kynar, copper, galvanized and stainless steel) may require a primer. It is the user’s responsibility to check the adhesion of the cured sealant on a test joint before applying to the entire project. Where incidental water immersion may occur, priming is required.

Apply primer full strength with a brush or clean cloth. A light, uniform coating is sufficient for most surfaces. Porous surfaces, may require more primer, but do not over apply. Allow primer to dry prior to sealant application. Depending on temperature and humidity, the primer will be tack free in 15 to 30 minutes and ready for sealant. Priming and sealing must be done on the same working day.


Apply sealant with a steady pressure, forcing into the joint. Dry tooling is recommended within 5 minutes of extrusion. Do not use soapy water as this may cause the surface to discolor. If tooling with solvent is necessary, use clean mineral spirits. Protect open containers from heat and / or direct sunlight. Do not use in joints deeper than ½' (13 mm) without the use of a backer rod. The depth of the sealant should be half the width of the joint. The maximum depth is ½' (31 mm) and the minimum is ¼' (6 mm). Sealant skins within 24 hours, is functional within 3 days and reaches full cure in about 1 week.


Clean tools and any uncured sealant residue immediately with mineral spirits. Cured sealant may be carefully cut away with a sharp-edged tool.