What are the general “rules” for applying building wrap (the most common one I see here is Tyvek). What are the best techniques for application,, what are the don’t do’s and what tips do you use/have learned about applying it. A sample question, – when it is applied,, what is the best way to seal the overlaps – tape or adhesive?
What are the alternative materials if any to Tyvek?
Thanks
Mark
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Replies
Hey, Gunner!
You want to give this guy some of your hard-won wisdom about housewrap? <G>
I should give him the number of my old builder. He's an expert at it thanks to me. :)
"Certainly it's nice to have some sort of "due process" with regard to moderator decisions (not that any law requires it), but (to borrow from another thread) there are "extremists" who cannot fathom why they are being censored, even though it's patently obvious to the rest of the peanut gallery, and they will, given a chance, drag out an argument forever, making the forum tedious for everyone else." DanH to Bill Hartmann August24 2008
ButtonKap nails or staples, minimum six inch taped seams. Just follow the manufacturers specifications.
A less expensive solution would be #15 builders paper. I've heard that it performs roughly about the same, but is much much cheaper. #30 has been successfully used under shingles for how long?
I've heard that felt outperforms housewrap but cant remember the details, and some swear by it. Saves money and supposedly better worth looking into. I second the button caps especially if going to be exposed for any length of time, amazing how much better they hold compared to when I started we used a hammer tacker, no comparison.
As a side note thanks to you for being more informative and less argumentive, so much nicer to have you around this way. (I've noticed your posts in the last couple of days seems like a different dude)
I'm going to ask a couple of really dumb questionsFirst - I'm assuming that the wrap is to reduce draft permeability, is that correct?Second, is wrap used everywhere or does it have specific uses in specific climates?Third - what advantage does felt have over plastic, sp with respect to draft permeability?Lastly, what is the correct way to handle wrap around openings - I'm wondering about details - how does it overlap or get handled at windows and doors?Lots of dumb questions. I'm not a builder but I've noticed that wrap on homes here in Ontario can look pretty variable . . . . sometimes it looks tight and sometimes it looks like it could blow off in a big wind.one more thing - in building that is increasingly tight, how much of this is because of wrap and how much is becasue of other building techniquesthanksMark
Yes, the primary purpose of housewrap is to reduce air infiltration. It has a secondary purpose of being a secondary rainshield, to keep rain that gets through the siding out of the house. How important this secondary purpose is depends on the climate, the type of siding, and (to a significant degree) personal prejudice. (If the secondary rainshield is an important factor then there are special varieties of housewrap better suited to this function.)Housewrap is particularly useful in colder climates, like here in Minnesota. When the wind comes whipping out of the NW at 25mph and -15F you come to appreciate the meaning of "air infiltration".An important feature of housewrap is that, while it's effective a blocking wind and liquid water, it lets water vapor pass through fairly easily. This means that, in colder climates, moisture that gets into the walls from the inside of the house can exit. If a vapor-impervious barrier were used (such as plastic) then moisture would accumulate behind (inside of) that barrier, soaking the sheathing, framing, and insulation.Housewrap needs to be somehow sealed to door and window frames to produce a reasonably airtight barrier. Exactly how you do this is as much art as science, especially when residing an existing structure vs building new. Tape, caulk, and other adhesives can be used, as appropriate to the specific circumstances.Housewrap does not have to be stretched drum-tight to be effective -- it just needs to be a continuous, unbroken membrane as much as humanly possible. However, if housewrap is installed loose and then exposed to the weather for any length of time the wind can cause it to flap, tearing holes and fraying the material.Housewrap is not the only way to build a "tight" house. It is an important aspect of the overall "system" when fiberglass batt insulation is used in conventional construction, but is less necessary with other insulation types.
Too much sanity may be madness. And maddest of all, to see life as it is and not as it should be! --Miguel de Cervantes
First clear your head of the term 'draft permeability'Drafts are convection cur5rents that contribute to or arise from infiltration of air from the exterior.Permeability OTOH, refers to the movement of moisture in its various forms through the membrane at hand.So good housewrap job reduces infiltration ( draft) of air into the structure, while allowing moisture to exit, yet still keeping a majority of the liquid water out.Tarpaper and Typar have roughly equal permeability for allowing moisture to move out, but typar is far superior at keeping drafts from moving through. Tyvek is more permeable than either.For details on wrapping the openings, look at the install pdfs online for eht makers.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Minor nitpick: "Permeability" can apply to any fluid (gas or liquid). The important traits of a housewrap are it's permeability to air (which should be low) and it's permeability to water vapor (which should be high). When "permeability" is used without qualification one needs to be careful to be sure that the intended meaning is what's understood.
Too much sanity may be madness. And maddest of all, to see life as it is and not as it should be! --Miguel de Cervantes
fair enough - coming from a waterproofing and roofing background, guess what my context is when I speak of perms
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Here follow this link. I think it has what you want as far as Tyvek goes. http://www2.dupont.com/Tyvek_Construction/en_US/tech_info/index.html
I also dug this up with the search feature. (thing don't work bad for me) It's a good read if you have the time to burn.
Personaly I'd explore felt.
http://forums.taunton.com/tp-breaktime/messages?msg=98740.24&redirCnt=1
"Certainly it's nice to have some sort of "due process" with regard to moderator decisions (not that any law requires it), but (to borrow from another thread) there are "extremists" who cannot fathom why they are being censored, even though it's patently obvious to the rest of the peanut gallery, and they will, given a chance, drag out an argument forever, making the forum tedious for everyone else." DanH to Bill Hartmann August24 2008
Is that last thread about cable the one you meant to post?
What the F????????? Stupid search function...........Wait one I'll find it again.
Here how's that coming out for you?
http://forums.taunton.com/tp-breaktime/messages?msg=108819.30
"Certainly it's nice to have some sort of "due process" with regard to moderator decisions (not that any law requires it), but (to borrow from another thread) there are "extremists" who cannot fathom why they are being censored, even though it's patently obvious to the rest of the peanut gallery, and they will, given a chance, drag out an argument forever, making the forum tedious for everyone else." DanH to Bill Hartmann August24 2008
That was a link to the deleted thread thread.
I was expecting a thread on using felt for housewrap.
I've got too many windows open that's what it is. Thank God I'm all done with p0rn for the day. That would be a problem. Boy Howdy. Have another Forrest incident. Wouldn't want that?
http://forums.taunton.com/tp-breaktime/messages?msg=93644.1
"Certainly it's nice to have some sort of "due process" with regard to moderator decisions (not that any law requires it), but (to borrow from another thread) there are "extremists" who cannot fathom why they are being censored, even though it's patently obvious to the rest of the peanut gallery, and they will, given a chance, drag out an argument forever, making the forum tedious for everyone else." DanH to Bill Hartmann August24 2008
That thread is barely over a year old. If I remember next Saturday night I might pop up a bowl of popcorn and sit back and rewatch it again. Kind of like watching home movies in the living room when you were a kid.
"Certainly it's nice to have some sort of "due process" with regard to moderator decisions (not that any law requires it), but (to borrow from another thread) there are "extremists" who cannot fathom why they are being censored, even though it's patently obvious to the rest of the peanut gallery, and they will, given a chance, drag out an argument forever, making the forum tedious for everyone else." DanH to Bill Hartmann August24 2008
.Housewrap dos and donts:DO use felt.DON'T use Tyvek or any similar plastic cr^p.
Don't know about general rules, but tacking with washered nails or staples is a good idea. And, if the wrap will be left exposed for any length of time tack well enough that it won't flap in the wind. Tape all seams.
How to apply the wrap varies a bit depending on whether this is new work or residing. For new work you generally apply the wrap, cut an X in the window openings, slip in the windows, and then caulk or tape them to the wrap. You can then apply self-stick rubber flashing over the window flange for additional security.
For residing you need to figure out how to seal the wrap to the window frames. If the frame has a nail flange then tape or rubber flashing can be used to attach the wrap to the flange, otherwise you need to carefully (tediously) tape the wrap to the outer edge of the window trim.
Use Tyvek tape (white) or "contractor's sheathing tape" (generally red), NOT duct tape or plain cellophane tape.