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charles
08-16-2008, 08:50 PM
Hey Bill,

Good article you wrote for the current issue of JLC. Questions:

1. When windows have been mulled around single 2 x 6 studs, which (if any) of the hybrid or manufactured pan systems can be used to flash around those intermediate studs?

2. Do you think that your custom-fabricated pans should be leak-tested like DWV pipes?

3. To avoid liability, I don't think I will ever fabricate my own pans, but there are just too many options to sort through among the manufactured full and hybrid pan systems. Make it easy for me and tell me which systems to favor and which to avoid. My priorities are as follows, starting with the most important:

a. reliability and durability
b. chemical compatibility with all types of rigid foam, caulk, membrane and housewrap
c. PVC-free for environmental reasons
d. easy to install
e. inexpensive

Bill Robinson
08-16-2008, 11:36 PM
Thanks,
1. any of the 3 dimensional flexible self-adhesives would be fine. If the window has a warning about asphalt based I would use butyl. And make sure the system is compatible.
2. I have done occasional tests on the custom fabricated ones and have complete confidence.
3. You are making me work on the last one. Except for the PVC-free exclusion I would go for the custom fab ones simply because they are so customizable. Of course you need a brake. I also like the other two shown in the article or I wouldn't have shown them. Then there is the copper from York, it is durable a
Your last question is for me like saying which way you should have your steak cooked.
One thing there is no doubt and that is that sillpans are an essential component for good door and window installation.
Bill R

m beezo
08-17-2008, 08:16 AM
Bill,
Help me out a little here and indulge a guy who just does not understand some things about construction.

First there have been thousands of homes built without every having a sill pan ever put into place. Secondly, I have only recently been hearing about them-say last 5 or so years. Thirdly, how many folks actually use them on a consistant basis. Forth, it seems like another step that adds to cost and time to do a job.

So, is it a recent invention, a new code issue, something that the makers of the sticky wraps and PVC coil stock makers are pushing or really a necessary item to do. I am not on that many new construction jobsites so cannot really say if they are being used. I can tell you that I have yet to see one used. In fact most of the guys I know are just know getting into using the peel and stick tape for windows and such.

And as far as a premade one. Is that something that you buy when you order the windows and doors so it is sized to fit or something you buy somewhere else? If they are so needed it would seem that the window and door companies would be selling them to you as part of their package. I thought of that issue when you talked about compatibility of materials. Just had a guy who wanted to install some windows and after reading the installation instructions noticed that his peel and stick would not work since it was asphalt based and needed to be buytl instead.

How about a little help for the old dog to learn new tricks?

Bill Robinson
08-17-2008, 08:43 AM
How about a little help for the old dog to learn new tricks?
Sit. Stay.

Sill pans have been around for a while. My first exposure was with the GSM, galvanized sheet metal, soldered corners. They worked well but had to be ordered well ahead of time and were pricey.
A few use them regularly, especially on exterior doors. Think back to some tearouts you have done and picture the framing at the bottom corners of the openings, weren't there signs of water leakage? That could have been prevented with a sill pan.

Manufacturers are not even supplying the fasteners, sealants and flashings, and only marginally providing the instructions so it is not likely they will provide sill pans.
Seat belts are a good idea, why did it take so long for car makers to make them standard?
There are exceptions, Marvin offers a sill pan as an extra and other window manufacturers are including sill pans in the instructions.
I am in Chicago till Tuesday, come on up.
Or you can come down to NOLA and visit,and I will make you a believer:) In sill panning and gumbo.
Things are changin' dog and we must change with the times.
Bill R

Joe Adams
08-17-2008, 01:44 PM
Bill,

Great article on an important detail.

We've spec'd sheet metal pans in the past but they can get pricey and slow down the work while they're being custom fabricated.

I'm intrigued by the manufactured pans because they include a backdam and I'm not ready to invest in the equipemnt to make site-bent pans.

Does one manufacturer stand out above the rest?

Thanks!

Allan Edwards
08-17-2008, 01:52 PM
Bill,

Great article on an important detail.

We've spec'd sheet metal pans in the past but they can get pricey and slow down the work while they're being custom fabricated.

I'm intrigued by the manufactured pans because they include a backdam and I'm not ready to invest in the equipemnt to make site-bent pans.

Does one manufacturer stand out above the rest?

Thanks!

Joe

I've used these a few times. They are pretty inexpensive.

http://www.jamsill.com/pilot.asp

I use sill and door pans on almost all of my homes. Even for doors where they are clearly covered by porch roofs, we use them so that when HO washes down a porch or exterior water will not enter the house.

Joe Adams
08-17-2008, 02:35 PM
Allan,

Do you buy them direct or elsewhere?

Thanks for your help.

Allan Edwards
08-17-2008, 02:41 PM
Allan,

Do you buy them direct or elsewhere?

Thanks for your help.

Joe

I haven't used these in a couple of years, I now use a local company to fabricate them out of lead coat copper. The jambsill product is purchased via phone order, you have to measure the framed openings (within 2-3") and call in the order, they ship to you.

slimpickens
08-17-2008, 09:05 PM
I also enjoyed the article. Thanks, Bill. Now if I only I had made my RO's big enough to accomodate a sill pan, I'd use them. Marvin's specified RO's sure are tight! Holy cats!

Dancing Dan
08-18-2008, 01:58 PM
Indeed a great article. Just hope Kreg doesn't nail you for stealing his look.

Dick Seibert
08-18-2008, 03:37 PM
Beezo:


First there have been thousands of homes built without every having a sill pan ever put into place. Secondly, I have only recently been hearing about them-say last 5 or so years. Thirdly, how many folks actually use them on a consistant basis. Forth, it seems like another step that adds to cost and time to do a job.

So, is it a recent invention, a new code issue, .....
In the old days walls breathed, water ran in and ran out, the walls dried both in and out. I've torn into stucco homes built before the turn of the 20th century with no paper at all, much less no flashing or sill pans with no damage. Homes were sheathed with redwood boards with horizontal groves cut into them for the stucco to lock, redwood homes had no paper until about 1910 so the water could leak in and out without damage.

The problem started with plywood, we started sheathing with plywood instead of boards and started sealing the walls up, so water that got in, stayed in, getting trapped and rotting out the structures, then we started putting insulation into the walls, a material that held the water, rotting out our homes. Now that we are sealing up homes and not allowing our walls to breathe, proper flashing and sill pans are a necessity. So far, energy efficiency in wood frame homes has been a disaster, but the industry is learning, and this learning process is what you are seeing going on. The old Italian carpenters who trained me always said: "The wall gotta breathe" now we installing products to stop air-leakage and depend upon permeability, which may (or may not) work.


BTW, I don't use sill pans on some kinds of windows, aluminum or vinyl windows with integral nail fins, with integral fins you can flash and seal the water outside of the waterproof membrane, but many nail fins, like those on wood windows are attached and can leak into the window at the joint of the fin and the frame.

When you do use sill pans, be sure to leave the gap between the bottom of the window sill and the sill pan open so the water to drain out of the pan, otherwise you are trapping the water you catch in the pan rotting out the window sill. Around here Loewen leaves the bottom fin off so there is no chance of trapping water in the sill pan, but I've found from these fora that Loewen doesn't do that in all areas. I see in Bills article that he shows no sealant behind the bottom fin and the sill pan, that may (or may not) release the accumulated water, I prefer to leave the bottom fin off altogether, or at least cut two or three inch gaps in the bottom fins to drain the pans. The dumbest thing you can do is install a sill pan, then take a finned window, squirt sealant behind all fins and smash it against the flashing and sill pan, in effect trapping water in the sill pan, sill pans have to drain, that's the whole idea of putting a "pan" under the window.

davenorthup
08-19-2008, 03:14 AM
Joe

I've used these a few times. They are pretty inexpensive.

http://www.jamsill.com/pilot.asp

I use sill and door pans on almost all of my homes. Even for doors where they are clearly covered by porch roofs, we use them so that when HO washes down a porch or exterior water will not enter the house.

I agree - call them and they will ship them very quickly. I too use them on every door now and option for windows depending on the scenario.

They are slick and well worth the small investment... I think I ordered 20 for 3/0 and 5 for up to 6/0 and the total with shipping was under $300.

I though the same thing Dan...

Nice write up Bill. I am leaning to get a brake soon to bend my own metal b/c we have a limited supply of pre-made available flashings and no one reliable to ben d metal in 70 miles.

Dick Seibert
08-19-2008, 11:04 AM
I think something that is being missed here is the need for drip caps, to me drip caps are a necessity in every building except a stucco building, and if you place wood trim around windows (and doors) they are necessary on stucco buildings.

I've always had my tin-man make drip caps and sill pans as part of his job, when I had the window corporation there wasn't always a tin-man on the job, so I would him have make up 1,000 feet at a time (100 pieces) and store them in the warehouse to take up with every job. On a really good installation, which I've only done a few times, the drip caps are folded down on the ends and soldered, that has to be done on the job.

Mark Parlee
08-19-2008, 12:44 PM
Good article Bill

Dave get the brake you won't be sorry

I just cut my tapco max into a 4'-1" and a 6'-5" Used a skill saw

I will have to post some pics

Bill Robinson
08-19-2008, 01:55 PM
I think something that is being missed here is the need for drip caps,
Dick, there a lot of things not here, it was an article about sill pans.
Bill R
FYI building code requires a head flashing above any anything extending proud of the plane of the exterior cladding.

steve demetrick
08-20-2008, 08:51 PM
Working in coastal New England, I always prefer to install windows and doors with sill pans, especially when we're working on the ocean or the salt ponds. When the wind makes the rain fall up for the entire day, a pan becomes the last line of defense from wetting the framing. Between the fast growth lumber we use today and the level of insulation (especially the foam), it takes a lot longer for less water to dry out of the wall assembly. I'm currently working on a house built in 1893, remodelled (and fully insulated) in the 1950's, with copper pans under every window. Over 40 windows in the house and not a spot of rot in the entire frame, all thanks to the pans (and proper window installation).

Top Notch
08-25-2008, 01:59 PM
Not to be controversial but if you go through all the trouble of flashing the sides and top of the window, then tape seams of tyvek or housewrap you dont need to do these sill pans. Is hard to get paid for this kind of effort as it is. Old work on the other hand could have a terrible air barrier and the sheathing could soak water behind any self stick flashing causing water to pool at the sills and rot.

J.Buesking
08-25-2008, 02:14 PM
That's true Tom until the window fails and starts leaking. Flashing around it doesn't help much if it's leaking in the middle.

No one will pay for them here. I always use them on doors though. It's the only way there.

Bill Robinson
08-25-2008, 02:17 PM
Not to be controversial but if you go through all the trouble of flashing the sides and top of the window, then tape seams of tyvek or housewrap you dont need to do these sill pans. Is hard to get paid for this kind of effort as it is. Old work on the other hand could have a terrible air barrier and the sheathing could soak water behind any self stick flashing causing water to pool at the sills and rot.

You know Tom, you are exactly right.
As I travel around this great land I see several different ways to install windows, some following manufacturer's instructions and some not.
What is the fuss all about, right?

Most of these installations will not leak.
Some will.
How can you tell which are the leakers?
For those who can tell which ones leak, or in your case where you know they will certainly not leak, these details are not necessary, for the rest of us they are.
Bill R

Dick Seibert
08-25-2008, 02:59 PM
then tape seams of tyvek or housewrap you dont need to do these sill pans.
Not true, all weatherproof barriers are overwhelmed at some point and leak, once they leak they wet the substrate and depended upon permeability to "dry-out", at the point the weatherproof barrier leaks and is drying-out water can leak through the windows so you need something to flash and collect the water.

Attached is the water hold-out period for Fortifiber Kraft products, DuPont doesn't publish the water holdout for Tyvek because it never passed the 20 minute minimum required, I've heard that it's 10 minutes. Also attached is the water holdout periods for Fortifiber plastic products.

The facts are that if it rains long enough to overwhelm the paper your walls are going to leak, if there are windows or doors in those walls it's going to run out there before it can "dry-out", and you've got to manage that water.

Top Notch
08-25-2008, 04:00 PM
These are good installation techinques for sure. Just a tough sell. Diverting the water out of a sill is only as good as the next pentration it hits. Either your a detail orientated contractor or your not and many are not. If there were we would get more money for what we would like to do more often. The siding business has some of the sloppiest guys in it. My business has taken a big hit from quick fix, house flippers and hacks that are cost driven. I am about to do a reside with new Anderson windows, the existing windows have water stains all around them. Why...cause there is no tar paper,housewrap or extruded insulation behind the siding and the fascia boards are nailed right into the wall no rafter tails. When the gutters clog on the second floor, water fills the gutter till it reaches the spikes (which always get loose) and water drips right down the wall behind the window flanges. Do you think this matters to this client? All she is concerned about is how much and her window alarms. I will still do the right job. But 10 out of 12 bids people dont want to pay for perfect installations. I also forget some still use wood window and will fail I am just used to clad assemblies.

Bob Dylan
08-25-2008, 05:40 PM
Any window and any door can leak, if installation was substandard, and particularly so if the site is subject to heavy blowing rain.

Sill pans, when installed correctly, can divert the water that gets by the head or jamb flashing, and keep it from going inside the inner plane of the unit.

Those millions of door and window openings installed without sill pans, and that have not leaked yet, are the beneficiaries of good installation practices, broad roof overhangs, minimal blowing rain of any volume, and other things.

There are some good choices in products to use. Jamsill Guard, EZ-Pan by Carlisle, WeatherMate by Dow, and more. As far as I know, Marvin is the only window manufacturer that offers a sill pan as an optional accessory.

I was a corporate suit with ThermaTru doors before the 1999 buyout, and dealt with a lot of claims for product failure where leaking was the issue. We always recommended the use of sill pans as a leak avoidance measure, and whenever a badly installed door was re-installed and a sill pan used, leaking did not reoccur.

ThingOfBeauty
08-26-2008, 03:53 PM
We're using flex wrap, it's quick and simple and not that expensive. We apply it over a strip of through-flashing that we pull through the cladding (stone, brick, siding). Just a way to sleep better at night. And every house I've ever demo'd has leaky windows so this seems to be the least we can do.

Mark Parlee
08-26-2008, 04:46 PM
Doug
do you have any pictures of this detail?

Bob Dylan
08-27-2008, 07:34 AM
The features of a sill pan are, in order of importance:

1. Sealed returns up L and R RO jambs
2. Sloped-to-outside surface at sill, with return up-lip at inside wall plane

You almost get there if you use a piece of beveled clap siding to achieve your slope, then wrap the whole sill of the RO with a waterproof membrane material, doing all the heat gun stuff at the corners and the return to achieve your waterproofing at corners and the up-leg parts.

But without that inside lip, you still invite water in a hard rain blowing storm condition.

Why not be prepared for your next installation, and buy the sill products necessary for the job? What are you waiting for?

The only two products I know of with the up-lip at the inside edge are the JamSillGuard and the SureSill systems. SureSill is offered by Jeld Wen as an option, and they re-name it. The Marvin and Carlisle products have the slopes and side-ups, but no back lip.

Top Notch
08-27-2008, 07:54 AM
Let me ask this. Do you guys add dimension to rough openings to allow for sloped sills? What if you beveled the sill 2x4 about 2 inches from the outside? This would drain, use aluminum or flex flashing. I like the homemade aluminum and cedar siding idea better than buying a pre made. But beveling a 2x4 seems cheapest.

Allan Edwards
08-27-2008, 10:04 AM
While I think sloped sills at the frame stage are not going to solve the problem, sill pans are needed in many cases (especially stucco), sloped or beveled sills at frame seems like a no-brainer to me. I've tried to get my framer to do this but with not a lot of success. Of course maybe I haven't pushed hard enough. We always at 1/8" for the sill pan, and of course if you were to slope the framing member you would need to allow for that. I wish this (sloped sills) would become an industry standard.

S.Joisey
09-01-2008, 06:37 PM
WHen framing for windows, I leave room for the beveled siding. In old consruction where there isn't room, I'll bevel the sill 2x4.

David Meiland
09-01-2008, 11:26 PM
I add 1/2" to the RO height when framing a new hole, so I can stick a piece of bevel siding on the rough sill and then add my pan. I'm about to do a bunch of new windows in old holes and I'll saw a bevel into the existing rough sill.

Some of the better windows are the first to leak. The wood/clad units with mitered corners... you get a few years (maybe) with those before water starts going thru the corners and into your pan. I think with the welded vinyl units you get longer.

Dick Seibert
09-01-2008, 11:54 PM
David:

You are absolutely right, almost all the wood window companies miter their corners to make their frames out of one profile and save a dollar a window, I think Loewen and one from Missouri, I forget the name of it, are the only ones which actually still have their jambs land on the sill, and head over the jambs. As soon as the sealant in the corners dries out they leak into the sill pans, if you have them.

charles
09-02-2008, 07:57 PM
I add 1/2" to the RO height when framing a new hole, so I can stick a piece of bevel siding on the rough sill and then add my pan.

That strikes me as not only redundant, but if the pans have square dams, legs or flanges, they won't sit plumb on a beveled sill.

David Meiland
09-02-2008, 08:19 PM
Charles, don't underestimate the financial commitment I require of my customers. I either use Flexwrap, which follows the slope of the sill, or I order custom made metal pans that have a 5 degree slope, with a plumb face flange and backdam.

charles
09-02-2008, 08:32 PM
Wow, you're like Allan Edwards. What price range and square feet are your houses?

Allan Edwards
09-02-2008, 09:08 PM
Charles, don't underestimate the financial commitment I require of my customers. I either use Flexwrap, which follows the slope of the sill, or I order custom made metal pans that have a 5 degree slope, with a plumb face flange and backdam.

David, I like this idea (bevel siding). For the turned up lip on the back of the pan, wouldn't you have to open it up a little to allow for the angle of the bevel? Same for the turned down part that lips over the sheathing. Or maybe this is insignificant. But good idea, anyway. I may try it.

David Meiland
09-02-2008, 09:34 PM
Charles, around here we get serious gusting winds and driving rain in the winter. You have to do this stuff. Flashing membrane costs maybe $20/window if you use Flexwrap and Vycor, add another $50 if you get a metal pan. The guys who make mine can really turn them out quickly.

Allan, that's what I mean when I say "plumb face flange and backdam."

Dancing Dan
09-02-2008, 09:39 PM
We do bevel siding as well. And we generally use flexwrap or similar instead of sill pans. I have been making the perhaps mistaken assumption that even wind-driven rain won't penetrate very far against gravity. Although sometimes we do leave a little flexwrap to staple up to the window.

David Meiland
09-02-2008, 09:47 PM
Dan, with Flexwrap as the pan I use oversize backer rod and cram it in under the window, on top of the wrap, and *just* inside the interior wall plane (i.e. don't force it downhill at all, keep it as close to the back of the drywall as possible). My hope is that this prevents water from migrating uphill where it can wet the drywall. So far so good. We put windows in the last house in December and I got to look at all of the units during killer wind and rain. No sign of any water anywhere. I think part of this has to do with how the exterior trim is configured and what path it offers the water to get to the window flange at the bottom.