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Our caulk-in cornerseals offer similar performance to the groove-in cornerseals used with our Corner-Grooving System, without the expense of specialized equipment. Since they can be adhered into any corner with silicone caulk, they can be used on metal jambs, on wood jambs with applied stops, on thin wood astragals, and in other situations where grooving is not possible. With proper preparation, the completed installation will last as long as the surface finish.

WS04 in rabbeted jamb

Silicone rubber tubes are adhered
into corners with silicone caulk.


We offer five different sizes of superior-quality, thin-wall silicone rubber corner tubeseals to assure perfect sealing of any gap from 0 to 3/8” with virtually no noticeable increase in closing pressure. Use the following chart to select the proper size based on the gap measurements:

cross-section WS02 WS03 WS04 WS05 WS06
designation WS02 WS03 WS04 WS05 WS06
gap range 0 - 1/8" 1/16" - 3/16" 1/8" - 1/4" 3/16" - 5/16" 1/4" - 3/8"

Since gaps are rarely identical on different sides of a door or window, don’t try to seal all the sides with a single-size tubeseal. If necessary, you can even use two or three sizes of tubeseals on the same side: just insert the smaller seals one-half inch inside the larger seals to hide the transition. Always butt-joint cornerseals at corners since butt-joints seal better than miters and they make size changes less visible.

INSTALLATION: First clean the jambs with toluene, xylene, or MEK – do not use other solvents!. Apply a small bead of a commercial-grade neutral-cure silicone caulk such as Dow 795 into the corner of the rabbet or stop. Select the appropriate seals and press them into the wet caulk. Seat the seal with our WS96 roller tool or a convex nylon screen roller using very light pressure so the caulk does not squeeze out. The sash can be closed in as little as an hour, but overnight curing is preferable. Do not attempt installation when air temperatures are lower than 45°F or when rain is possible. It is essential to keep the tubeseals absolutely clean and until installed: clean off any dust with solvent.


caulking caulkable cornerseals

After cleaning the jamb, apply a small bead
of commercial-grade silicone caulk.



placing caulkable cornerseals

Select the best size of corner tubeseal and tack it into place
with your fingers. Keep the tubeseal very clean: don’t let it
touch the floor. Store the unused tubeseal in a plastic bag.


rolling caulkable cornerseals

Roll the tubeseal into the corner. Only very light
pressure is recommended: no caulk should
squeeze out. The sash can be closed in one hour.


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