Sloped Sill Pan for Sliding patio door
twotonwonton
| Posted in General Questions on
Hello,
I recently bought a Marvin Modern sliding glass patio door (95″WX84″H) on Facebook marketplace. Everything I have read on this forum seems to promote the use of a “sloped sill pan” below the door before installation.
I am uncertain how to install the track of the sliding door over a “sloped sill pan”. The online installation instructions for the door require a perfectly level surface for it to sit on. Do I use multiple counter shims directly under the track to compensate for the sloped pan?
Any advice is welcome.
Thank You!
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Replies
Last week I was at a building science conference with industry big-wigs like Steve Baczek, Jake Bruton and Ben Bogie. This issue came up and they had two suggestions.
1. Use a flat sill pan that includes a fabric that draws moisture out of the pan. I don't recall the product name and it's not showing up on Google but I can get it if you're interested.
2. Create a recessed, sloped sill, waterproof it, then add closely-spaced, tapered shims that are perfectly level, and use waterproofing tape or a fluid-applied membrane to hold them in place. It doesn't meet manufacturer requirements but if they are perfectly level and closely spaced, they should work fine.
A third option, and what I almost always do, is just make a flat pan but be very careful about creating a watertight back dam. Doors should always be covered and protected from rain most of the time so they should be exposed to potential leaks very often.
Thanks, Michael- this is very helpful! I think I am going to go with the third option you give.
how do you feel about https://www.suresill.com/product/suresill-sloped-sill-pan for doors and windows? i used one for a tilt and turn window in my 2x4, 1/2" sheathing, ~1.5" air gap, full sized brick siding home. was a little awkward to trim around. seemed okay for how i used it and integrated it into a brick window sill -- would've been a million times easier with stainless steel thru wall tape..
CS55, There are various pre-formed rigid plastic pans like those; long ago when they were new to the market I used them on every window in a house with a lot of windows. Then when trimming the interior, realized that every single extension jamb needed to be taper-cut. So I've been cautious ever since but they should work.
thanks for the reply. its been hard to find many remodel details for block frame/flangeless windows in 2x4 homes + full sized brick veneer siding.
yea, the interior was a little annoying to trim. theres really no room for a sill or returns/jambs for a 2.9" deep window thats flush with the sheathing in a 2x4 wall with 1/2" sheathing. 3/8" drywall has been a godsend for the worlds tiniest returns while having to mud around the window hinges.
essentially i went for this https://i.imgur.com/Z6DPQbA.jpeg .. with some modifications for the exterior. i removed the old brick sill, did metal flashing like that photo, then placed the plastic pan onto it. the bricks butt up against the window frame, they don't sit under a sill like that picture.
i think it'll be "fine". the house was built 20 years ago and i've replaced almost all of the windows and theres been zero sign of rot. the existing windows were original flanged windows that had no sealant or tape and the previous brick sill also butted up against the window frame, not under it. there was also zero flashing under the brick sill and the only thing keeping water out of the cavity was caulking between the window frame and brick.
for the final window i'm going to try https://www.masonrydirect.com/products/york-304-stainless-steel?variant=39454067130439 for the sill details :\ hope it goes smoother.