Sill flashing

Q: Do you want flashing under stone masonry or precast sills?

Yes. Even one-piece stone or precast sills might take on moisture in the interface from the sill and masonry jamb, window failures, material imperfections, or porous material structure. The main purpose of flashing under sills would be to safeguard the wall below. If there’s a moisture transmission problem, it’s simpler to repair a sill rather than fix the wall. Quite simply, it’s more suitable to

collect and divert moisture towards the outdoors as rapidly as practical rather than for you to it finds through-wall flashing elsewhere.

Generally, whenever flashing is set up in a masonry wall you should also install be sad vents – masonry sills aren’t any exception. Without weeps, water can become trapped behind or underneath the sill. This water could eventually go into the building or deteriorate the mortar and/or sill through freeze thaw cycles.

Weeps could be set up in sill mind joints or between your sill and the flashing. Types of under sill weeps can include: rope wicks, tubes, half-tubes, or cell vents laying on their own sides. Obviously, care should be come to keep mortar from clogging the be sad vents…

For more info download the pdf below:

Download pdf


Installing a door sill pan


Billy Snow: QUESTION: is the flashing under the sill pan extra protection. you can counter sync another flashing to the sill, right

yrulooknatme: +Brian Drumm Your gonna add holes when you screw that threshold down?? How do you treat that ?

Brian Drumm: There are no fasteners added that go through the flashing pan. The bottom track of the door is one continous piece of aluminum and is held in place by fastening into the studs on both sides.

Jeffrey R. McVannel: Most installation instructions I've seen say to place caulk under the (sliding glass) door. It seems caulk would prevent the plastic sill pan from draining. Do you recommend no caulk under the door?

Brian Drumm: Jeffrey R. McVannel \nI normally run a bead of silicone along the inside leg of the pan. It air seals that edge without getting in the way of moisture draining out.

larry averitt: Nice work.

Cathy Wong: Is the grace vycor flashing tape 4 inch or 6 inch?

Brian Drumm: Cathy Wong \n6 inch