Wrong window for siding? - InspectionNews

Vern Heiler · #1 (**permalink**) 10-02-2008, 06:20 PM

New construction Hardie Board siding and vinyl windows. The windows are: MI Windows & Doors Model # 4300.

None of the windows are sealed at the siding. The windows are flanged type "self flashing" if you believe in that, and have what the manufacture calls (intergral "J" channel).

I see this type of window with vinyl siding all the time, never caulked at the edges to the siding. The manufactures installation instructions for there vinyl windows has this:
11. ALLOW A 1/4” GAP BETWEEN THE EXTERIOR CLADDING, SIDING, BRICK, STUCCO OR STONE AND THE WINDOW FRAME ON ALL SIDES (EXCEPT VINYL J CHANNEL).

THE GAP (EXPANSION JOINT) SHOULD BE FILLED WITH CORRECT SIZE BACKER ROD, THEN SEALED WITH A HIGH GRADE EXTERIOR SEALANT AND WILL NEED TO BE MAINTAINED.

Is the 4300 window designed for vinyl siding only? Can they be used with cement board siding? I don't see how you can seal at the edges with the intergral "J" channel in the way. There is no visible flashing or drip cap at the top of the windows either. Water will go behind the siding, leaving the house wrap and flashing as the only barrier to the sheathing and studs.

Do I recommend installing a drip cap or flashing at the head and sealing at the side jambs, or state "wrong window for the siding"?

Any help is appriciated.

Thanks

wayne soper · #2 (**permalink**) 10-02-2008, 09:48 PM

The J channel is a slot that the siding slides into. Designed to make the siding application easy and leakproof.The back side of it is much wider than the outside and should be taped to the house wrap.
Any water entering in that gap you are worried about will drain down along the edge the same as it would with vinyl siding so I don't see it as a problem. Unless the manufacturer of that window specifically says it is only to be used with vinyl siding. Or unless it's not taped like 99% of the applications out there.

Vern Heiler · #3 (**permalink**) 10-02-2008, 10:09 PM

Thanks Wayne, I don't know if it is flashed to the house wrap or not, don't eaven know if there is house wrap? I'm sure there is, nice 3,000 sf. house! The problem I have is where the manufacture says to leave a 1/4" gap to be caulked, except for vinyl J channel. Do they mean the vinyl J channel on there window or vinyl J channel of the siding?

Brandon Whitmore · #4 (**permalink**) 10-02-2008, 10:20 PM

I'm not gonna look up the manufacturers installation instructions, but I think that installation is crap.
On vinyl siding installations it is typically recommended to run the bottom strip of flashing back to the exterior of the siding right beneath the window so water does not travel all the way down the wall-- did they do that here? Also, vinyl siding breathes pretty well. How often are housewrap/ flashing installations done right? I just think that installation is asking for it.

wayne soper · #5 (**permalink**) 10-03-2008, 05:43 AM

http://www.miwd.com/pdf/41.pdf
heres the window
http://www.miwd.com/_pdfs/2006_Instructions_Vinyl.pdf
heres the instructions

Jerry Peck · #6 (**permalink**) 10-03-2008, 09:41 AM

Vern,

Based on the installation instructions (than you, Wayne) the window looks to be installed as it was designed to be.

Granted, you cannot see how it was flashed to the wall or WRB, if at all, but, can you see that on other windows after the siding has been installed? Nope. So I would treat that as I would any and all other window installations where you cannot see it before the siding is installed.

Brandon Whitmore · #7 (**permalink**) 10-03-2008, 11:16 AM

Those instructions don't say you can't do what was done, but they are pretty generic installation instructions for all of their windows.

That kind of window is gonna channel quite a bit of water behind the siding, and I don't like it either way......... It's just asking for problems.

I put in an e- mail to their company because I am now curious. I'll post their reply

wayne soper · #8 (**permalink**) 10-03-2008, 02:42 PM

OH, you mean like a normal window

Billy Stephens · #9 (**permalink**) 10-03-2008, 03:29 PM

Quote:

Originally Posted by wayne soper

OH, you mean like a normal window

.
Yep!
.

Brandon Whitmore · #10 (**permalink**) 10-03-2008, 06:59 PM

Quote:

OH, you mean like a normal window

The new design of windows are problematic, but at least there is usually a spot where you can caulk the frame to the siding to limit the amount of moisture that channels to the typically improperly installed WRB and flashing. (run- on sentence huh)

This design just makes things worse is all. It's not like the manufacturer of the window will stand behind the installer of the window, flashing, and WRB-- they just make the windows and tell everyone to keep the water out somehow........ but it's not their fault if water gets in........

Mike Schulz · #11 (**permalink**) 10-14-2008, 11:47 AM

I have been fighting this with the builders and manufacture window rep for years. I call out everyone. The rep is going to speak with the large builders and explain to them that they don't care if there is siding on the house or not. They only care about the installation of the window in the wall. They say follow siding installation instructions. I can't find anything in siding instructions on this particular question. The rep was suppose to get back with me when he spoke with the builders in question but I haven't heard from him in a month.
Anyone interested call Tim at 717-365-3300 ext. 2512 and let us know (MI windows and doors). Maybe if enough of us complain we can get this changed. Until then I will keep calling it out and fight with the builders. Reason this is on going one of the builders was pissed at me because I call it out on his stuff for 3 years and he is sending a complaint to the licenses board.

My beef is the siding is notched up under the integral "J" of the window and if it is a second storey window it has to run all the way to the foundation to exit.

Jay Ray · #12 (**permalink**) 10-30-2008, 02:50 AM

Ask for pictures of the home while it was under construction. Most homeowners document the building process for their scrapbook.

I would like to see images of any window or door before the siding was installed. Most likely they did not tape the nail flange as it IS NOT part of the flashing package! If they did tape the flanges, is the tape applied to the house wrap?

The window design is perfect as long as it is an intragrated nail flange. It is the contractors lack of training and the instalation method that is the issue.

You do not seal the siding to the PVC "J" channel. This traps moisture. If the window is flashed properly you want water to flow out ASAP and air to circulate around the window to dry it. The flashing and house wrap give you a surface for the drain plane. Simple rule: the faster water flows in and out along with the higher the air circulation causes less issue. (If flashed correctly of course)

Hardy board is pre-punched. The nails fit loose in the punched holes. The nail penatrated the house wrap thus voiding the air/water barrier. Water follows the nails into the sheathing. I will almost always see 1" round rot spots where the siding nails attach to the sheathing after 5-7 years.

OSB in the Northeast is proving trecherous to this phenomenon!

Jay Ray · #13 (**permalink**) 10-30-2008, 03:33 AM

Let me give you the truth about PVC products and the USA.

PVC windows were invented in Europe after WW2. No natural resourses after the bombings. The Germans made many mistakes and learned from them.

PVC products hit Canada in the 60's. They made the same mistakes the Germans made in the 40's.

PVC then came to America in the 80's. We are STILL making some of the same mistakes both Canada and Germany made years ago!

I went to a window training school in Canada years ago and got this info directly from the CEO of a major PVC extruder.

"We Americans are proud and want to do it on our own" he stated. We refuse to learn by other countries...it's just they way we are. I can give several examples but don't have time. Instead I will give one we never think about.

Sunlight....ie, UV rays hardens the PVc and you all remeber how bad it faded and cracked in the not too distant past. Germany had this issue in the mid 40's and solved it by adding a UV inhibitor. Canada had the exact issue in the 60's. American PVC products have been adding UV emolents only in recent history. Refering to PVC siding and PVC window products.

I don't want to pick apart the window instalation guide sent but will tell you from experience it has a major flaw. The #1 issue with sealing PVC to any substrate is expansion/contraction. (I attended a Dow Corning class some time back). Why on earth would you rely on sealant behind a pvc nail flange to a wood sheathing product? It's not going to last and experience shows us it is hit and miss. Also Germany and Canada learned about Micro-Cracks. You are told to hold the nail off PVC siding by 3/16" for movement. What happens when you nail a window flange tight. Driving home the nail causes tiny cracks in the nail flange. When the temperature changes the PVC cracks. Some cracks lead into the frame of the window. This bypasses the sealant behind the nail flange. This is why Vicor and Grace makes self penatrant tapes. It covers these simple issues found many years ago.

For any contractor as well as anyone in the building trades I would refer you to Jeld-Wen's site. I go to many window and door manufacturues schools (as many as 4 times a year in 2 countries) to learn the LATEST in window/door installation methods. J-W has the most comprehensive installtion method I have ever studied. They happened to put their method together after buying a Canadian window co. a few years ago.

Jerry Peck · #14 (**permalink**) 10-30-2008, 06:40 AM

Jay,

Excellent information on that Jeld-Wen site.

Includes a "drain mat" which I have not seen before, looks like it provides an angled, slope-to-outside, draining surface.

Also noticed this in the installation instructions: (underlining and bold are mine)
- AFTER INSTALLATION

- - 1. Install exterior wall surface within seven days of window installation.
- - 2. Maintain gap of 1/4"-3/8" between window frame and final exterior wall surface (siding, stucco, etc.).
- - 3. Seal the gap with backer rod and sealant. Do not apply sealant on top of window frame or drip cap if present.
- - 4. On the interior, seal the void between the rough opening and the window frame with backer rod and sealant, or with low expansion foam. Do not use high-expansion foam as this may cause frame deflection.
- - 5. Adjust window for best operation.
- - 6. Protect recently installed units from damage from plaster, paint, etc. by covering the unit with plastic.
- Note! For integral J-channel vinyl product installed into a structure with shiplap siding, no expansion/contraction joint is needed.

Brian Robertson · #15 (**permalink**) 11-02-2008, 04:25 PM

So now I am curious, does this window need to be written up?

Mike Schulz · #16 (**permalink**) 11-02-2008, 05:01 PM

Quote:

You do not seal the siding to the PVC "J" channel. This traps moisture. If the window is flashed properly you want water to flow out ASAP and air to circulate around the window to dry it. The flashing and house wrap give you a surface for the drain plane. Simple rule: the faster water flows in and out along with the higher the air circulation causes less issue. (If flashed correctly of course)

Jay,

If you don't seal around the window because of what you described why caulk anything on the exterior. Siding butt joints, siding to corner trim boards, etc.

Quote:

If the window is flashed properly you want water to flow out ASAP and air to circulate around the window to dry it.

If the window was caulked there would be limited amount of water that would get behind it. Also the siding is only caulked to the frame and if water needs to get out it can exit out the bottom of the panels that are lapped. The overlapped panels are open for breathing. and if water does get behind it it will still have the same drain plane. The siding gets caulked on the surface to the inner part of the fin. The back of the siding is still open to the wall for drain purposes as you described. I am not understanding why caulking would trap water. The caulking just limits the amount. If water gets in the top channel of the window it will run down the sides and behind the notched siding that is installed under it. Then it needs to find a exit point whether at the foundation, nails in the wall, through the wrap (vapor) or any other exit point.

M/I has a window that is exactly the same. One with and one without the "integral" channel. The one with out the channel gets caulked and according to the builders the ones with a channel does not. Now why caulk one and not the other. The one without the channel gets caulked so would that not trap water as you described?

Just trying to get to a reasonable conclusion so I can explain it to my customers.

Jerry Peck · #17 (**permalink**) 11-02-2008, 05:12 PM

Quote:

Originally Posted by Mike Schulz

M/I has a window that is exactly the same. One with and one without the "integral" channel. The one with out the channel gets caulked and according to the builders the ones with a channel does not. Now why caulk one and not the other.

Mike,

The one without the integral "J" channel gets a "J" channel installed adjacent to the window and into which the vinyl siding goes.

Does vinyl siding get caulked into each and every "J" channel?

Do the "J" channels get caulked to the sides of the adjacent windows?

Mike Schulz · #18 (**permalink**) 11-02-2008, 05:27 PM

Jerry,

The windows with out the channels around here most of the time is with cement fiber. The ones that do get Vinyl "J" channels are caulked to the frame. Also with or without the "integral channels the vinyl siding gets flashing in the bottom corners and overlaps the adjacent panel below it, nailing strip to direct water to the weep holes in the bottom of the panel.

Lets stick to cement fiber, that is the question about caulking.

Ted Menelly · #19 (**permalink**) 11-02-2008, 05:28 PM

Not much of any kind of lip at all on the sides of those windows. Can't caulk the vinyl siding for spacing for expansion and contraction.

New window time.