Had a builder we recently picked up walk past as I was rolling ice&water shield around my window hole. He asks what I was doing and I told him I was of course “flashing” (here’s your sign)…. He says he has never seen a framer do that before. he said the last framer just nailed the window in , (no caulk) and tyvek taped the nailing fin to the house. ?????????
Is that even allowable by code? Am I missing something here. Never heard of just tyvek tape.. No caulk? huh. That tyvek tape must be some phenominal stuff. Maybe I should try that instead of step flashing my dormers. lol
what do you use, and how do you flash a new construction window?
Replies
I use Carl Hagstrom's method, which is detailed in the JLC issue from a month ago. It uses peel-n-stick flashing, along with Flex Wrap for the pan. Basically, the tyvek goes on first, then the flex wrap, then the window, then the peel-n-stick. There is a nice detail at the head.
You can do a fairly good job with Vycor, which I presume is what you were using since I&W is 3' wide and intended mostly for roofing. With some care you can make a decent pan out of it, not perfect but decent.
Nailing the window directly to the sheathing is skipping at least one step. There is no reason not to protect the opening first, unless you're lazy.
Take your checkbook when you go to buy Flex Wrap.
Thanks for pointing out that article... 6/2005 JLC, p65. I was very interested in the sill seal wrap the guy is using: Tyvek Flex Wrap, but it's is quite pricey... http://waterdamageprotection.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=TYV-003&Category_Code=tyv
Anyone know of a similar product that is more moderatly priced? The elasticity is what makes the Tyvek Flex Wrap unique... For example, at one of the building supplies I go to they have some foil faced bituminious peel and stick window flashing tape that is ~$12 for a 100'x4" roll - doen't have a name brand on it... It's great for on top of the flanges, but I'd still like to find a better method/product to do the sill.
I have a house that will be at this stage in about a week.
Thanks
I used ice & water shield - given I had some left over from the roof. A little thick though, and if I were to do it again probably would have used Vycor, but it wasn't readily available locally. The Tyvek proprietary stuff would have cost me about $400 - a little too pricey, but it does look like it works nicely. Alot of guys around here use Visqueen (black poly)and caulk the nailing fins(if that), which IMO is not as effective as a self adhearing flashing. Also some window manufacturers require the use of self-adhearing flashing - this might affect the warranty I suspect.
I use Fortifiber made EZSeal . . . where to find? I know Carlson Systems deals with them. Whether or not your local outlet carries it is another issue. I think I pay about $16 for a 75' roll of 6"."If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man." - Mark Twain
I used that product on a few houses. Centex uses it here locally too.
http://www.fortifiber.com/FBSG/moisture_control_flashing_systems_products.htmhttp://www.fortifiber.com/FBSG/pdf/data_sheets/moistop_ez_seal.pdf
it is about $16 a roll here too. Only 1/2 of the width has mastic on it though which makes it easy to work with, but I'm not so sure it really seals as good as flashing tape with mastic on the full width. Right now the houses I'm doing have a window trim detail of 5/4 x 4 around the top and sides and a protruding sill below. With all that nailing going on around the window I'd like to get as good a seal as possible and I'm not totally sure how well that product seals around nails - it's more like a paper. The main thing is though that it lacks the elasticity of the Tyvek product I was asking about. There is a pic on this page: http://construction.tyvek.com/en/productServices/Flashing/flexWrap.shtml which is not a very good pic, but if you look closely you may get the idea. If I could get my hands on a product like that at a reasonable price, I'd use it on ext doors too.
I have to special-order the Flex Wrap, and I think it's nearly $200 per roll for the 7" version. Yow... but what's going to do the job better but a copper pan? I have used the PVC sill pan kits but they cause a big build-out around the sill and then you're futzing around trying to relieve the siding and trim to make them lie flat.
There is a competitor product to Flex Wrap advertised in the new JLC.... MFM Window Wrap-Flex... 800-882-7663. Looks like they have 8 types of roll flashing material.
OK - I can get a roll of the 6" for $35 from ABC supply which is near by... cool.
http://www.abccatalog.com/store/listcategoriesandproducts.asp?idCategory=230
See any reason not to use it below a door threshold before the door is installed?
I guess I would have a very slight preference for a galv or copper pan under a door sill. The movement of the sill over time as people step on it might eventually pinch a hole in the roll-type materials, since they're fairly soft. I have a real easy place to get pans made here, so I do that for doors. Using a rolled material would certainly be better than not. The MFM products at the link your posted are way cheaper than what I paid for the Dupont. Let us know how it is if you buy some.
matt, we use Grace membrane ... cut our strips off our 3 x 75 roll..
on hot days we use it as is..
on cold days we stretch it with a heat gun..
we don't use tyvek .. we use 15# or 30# feltMike Smith Rhode Island : Design / Build / Repair / Restore
Mike and other posters,
Does the Grace membrane stretch around the inside corners like the flexwrap? If so that would be ideal and economical. I'm doing mostly replacement windows these days and I've had the same trouble that David Meiland mentioned with the PVC pans. I've been considering using PVC shower pan liner and gluing the corners to get a more bullet proof installation, that some of these replacement situations require. I can get Moistop locally, for a considerably higher price than whats been reported here, (Gonna complain about that tommorow) but I havent seen any of the other products yet.
Mike: the Tyvek product we are talking about is an elastic flashing tape, not the house wrap.
matt.. in most instances, people are using BOTH.. the housewrap .. AND the tyvek flashing
we use neither..
we make our pans out of Grace .. sometimes copper..Mike Smith Rhode Island : Design / Build / Repair / Restore
Mike, which Grace membrane product are you referring to, Vycor or something else?
I have used Vycor to make window pans and it is an acceptable method if done with a lot of care. The material stretches a little, and can be made to cover the corners of an opening.
First apply a piece to the wall below the opening and dress it into the opening, onto the rough sill. Then apply another piece, first onto the rough sill and then dressed down onto the wall. Be very careful to cut into the corners nicely, and stretch the material, and you have a decent pan.
Both pieces of Vycor are done AFTER the weather barrier is already on the wall, and lap over it below the window, in case that's not obvious.
I'm basically in love with super-slick materials like Flex Wrap and so I use them. Good business decision... who knows... but I have had customers walk up and say 'wow, that's really clever, you must be god among carpenters'. That's right, say it again, ma'am.
I hear you. I was tempted by the Flexseal too but it was pricey (I was doing my own home). I did essentially the same thing you described with the I&W shield, but it was rather thick. The bldg. inspector was pretty impressed though.
Layering the materials correctly is very important. You don't want water to be able to get behind and find it's way in. Widows with a vinyl nailing flange are handled a bit differently than those with attached wood trim. A vinyl flange is done by putting the membrane on the bottom of the RO first, it is often cut to extend past the sides and bent over the sill. The window is then installed, the side membrane is placed over the nailing flange, extending past the top and lapping over the bottom membrane. The house wrap is either slit or pulled back so the top membrane can be installed on the top and the wrap laid over that and the seems taped. With a wood trim window, the RO is wrapped before the window is installed with the same lapping procedure. Again, the wrap is pulled or slit and a prebent metal flashing is applied to the top of the trim. Making sure that the wrap is over the flashing prevents water that may get in above from finding it's way behind the flashings. It's also a good idea to caulk the back of the nailing flange or trim before installing. The lack of the wrap detail is leading to premature rotting of windows and doors, since the wrap provides a water resistant surface and a good place for the water to run. This is also an important detail on other flashings like those on a dormer wall.
Like you. But I'm the odd man out here. I had to fight to get someone to actually carry the membrane, and they're not happy because I'm the only one buying it. (But thankfully, until the pallet runs out, I'm golden!)
What you describe is exactly what "typical" is around here. I don't understand it either. You walk in a house thats at trim stage and water is coming in around the window, running down the wall, and some bright light says oh when we get the vinyl siding on next week it will all be fine. Gawd I feel sorry for the suckers who end up buying these places.
You can win the argument for your own sanity. Just gotta teach and educate people who don't currently know any better. If there's builders you like working with, and the flashing thing is their major fault, tell them why its better your way. You get points for having two functional brain cells, they make better homes. And you get less call backs.
"If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man." - Mark Twain