Replies

1. 
   cavemike_ | Dec 23, 1998 05:00am | #1

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   For the applications you listed; corners,window and door openings, behind siding joints I prefer to use 45 mil epdm. The stuff just won't deteriorate within our lifetime.

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   alan_joseph_samson | Dec 23, 1998 05:27am | #2

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   What is 45 mil epdm?

   Thanks.

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   John_Wells | Dec 25, 1998 11:46am | #3

   *The JLC has done a series of articles this year on housewraps and water infiltration thru them. There has been quite a debate on it, given all the lawsuits for faulty construction. Owners seem to lack a sense of humor when their almost new house has extensive rot.My marina laundry room building (Anacortes, WA) is showing some interesting signs - paint peeling on the weather side (we get some healthy winter gales from SE) and well advanced brown cubical rot on the inside corner of the window sill on that side. I'd love to get the siding off to see what is happening. I don't think it will be a pretty picture, given the amount of BCR. (And this is not a cheapo building. Nicely detailed, primo metal roof, good materials, good carpentry, bucks spent.)I suspect a failure of or lack of drainage plane behind the siding. When you get whole gales or storms, you can expect water to be blasted into any crack. Then what happens?

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   Guest_ | Dec 25, 1998 08:16pm | #4

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   John, Thanks for replying. I'm interested in whether you used a particular kind of housewrap and what type of siding you have on your building. How long has the siding been up?? What type of window trim and detailing did they use? Thanks again.....

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   Guest_ | Dec 26, 1998 11:00am | #5

   *Virtually everything I've put up has been ply sheathed with Tyvek wrap, cedar clapboards and wood windows, usually Marvin. The sheathing is run horizontally, but not all my joints fall on framing lumber. Obviously the ends hit the studs, but I run sheathing from the first floor studs, over the second floor rim joist, to the second floor's studs to tie the structure together.The housewrap is run top to bottom, regardless of the CURRENT use of the attic. I figure someday, someone is going to do something up there...same with the garage.I also use 30 lb felt on all 4 sides of windows and doors, lapped for drainage. I'm not much for caulk, but do shoot a bead on the back of the window trim as the windows are installed. Flashing is split between Cu and Al, depending on the job. I always have overhangs of at least 16 inches on the main roof, usually less on bumpouts to stay in scale. This helps a bit in keeping water off the walls and especially off the second floor windows. Obviously, if it's really blowing...Clapboards are furred out from the wrap with mesh screen at the bottom opening, though I have had a couple folk who INSISTED the siding be tight to the sheathing/wrap. They signed off, just in case...I typically don't do anything special behind the siding joints, though the clapboards are cut slightly long and snapped into place. The only time I flash the clapboard joints is if it is a coastal/island/exposed structure subject to higher then typical wind loads.I've been fortunate to have had no water or moisture penetration problems to date (at least reported!). I'm fairly happy with the housewrap I use, in spite of the surfactant issue.

4. 
   cavemike_ | Dec 26, 1998 03:04pm | #6

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   45 mil epdm is one of the single ply roofing membranes that is 45 thousandths of an inch thick. I don't remember what epdm stands for but it is a black rubber-like compound.

5. 
   Guest_ | Dec 26, 1998 08:11pm | #7

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   Anytime I travel, I have to swing through the new building areas and check up on current trends. I have observed that 99.9% of all builders seem to use housewrap on the heated or cooled portion of the structure and not on the large attic areas that are exposed with these high pitched roofs OR they don't use any housewrap at all.

   This leads me to conclude that they value the wrap as an air infiltration barrier and not as a water shedding membrane OR they see it as not being of any benefit whatsoever for either one.

   Most of these new homes were sheeted with 4x8 sheets of OSB or plywood installed vertically, with all joints landing on a stud or a top or bottom plate. Evidentally many people feel this is airtight enough.

   As for the water shedding consideration, many builders seem to prefer using roofing paper on the corners and around the windows and doors and in some cases behind the siding joints.

   Your thoughts on this matter, please !

6. 
   Guest_ | Dec 26, 1998 08:11pm | #8

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   Mongo, Sounds like a bunch of good ideas to me!