Quality of housewrap question

12 Replies

Hi everyone,

I'm building a new property with the intention of house hacking. The house has been framed, windows installed and drywall put up. I've been doing a lot of research into the WRB that has been installed. It is a generic woven perforated product unlike Tyvek homewrap. I can't find much information except for its ICC-ES evaluation sheet.

I asked the builder why he used this instead of Tyvek and it has taken him a week to answer and even then the answers have been vague ("it should behave the same"). I then asked him if he used this product in his last build. No answer. However, I found some information online that states that Tyvek homewrap was used in the last property he build. This is setting off red flags in my head.

I am halting the build until this product is removed and replaced by Tyvek. Do I have a foot to stand on by doing this? What options do I have at this point? I am also concerned about where costs have been cut in other aspects of the building.

Thanks for your advice,

CJ

Hey Chris, 

Not sure that your wrap MUST be Tyvek, specifically-- I'm sure there are other decent wraps out there.   And I'm no Builder.  HOWEVER, I'm replying because I recently watched a youtube video about someone's opinion of the "5 dumbest building products " that contained something like what you described.    See if THIS  link works.  

That said, I'll note that the builder in question was called out by others pretty harshly in the comments concerning exactly that product, and it's a pretty new video.  Caveat Emptor.

Good luck.     

Hi Steve,
Thanks for the reply. I agree that that there are products that are probably very similar to Tyvek in terms of structure, but the one that he is using is definitely not one of them. In fact, your video is very helpful. That looks identical to what they put on my house.

CJ

In my opinion, the vast majority of woven WRB's should never be used. With that said, most people, GC's and builders included, don't think twice about using them. 

I don't think most people even take the time to educate themselves on the different options available and instead defer to the lumberyard. If the builder doesn't spec a particular product, the lumberyard will select for them. With budget always being a factor, this usually means a woven product is included. 

In order to properly select a WRB, you must look at the entire wall assembly. Perm rating and type of cladding are probably the most important factors. There are many options on the market today, but I'm still a fan of time tested spun-bonded polyolefin, like Dupont Tyvek. 

Ultimately, you are the client so the builder should replace it, but expect to pay for it. If Tyvek wasn't specified initially, this is a Change Order. 

Tough to say if your builder is cutting corners elsewhere. As I said above, it could be ignorance regarding the importance of a quality WRB. 

Hi Ben,

Thanks for your response, that was very helpful. It seems to me that there is this grey area regarding what is specified or not, particularly in the fundamental building materials. It seems to much detail for a contract  to specify OSB vs plywood subfloor, joist material, etc. Honestly, I don't know enough about the pro and cons of the materials to catch it even if it were individually specified in a contract and the WRB falls into this category. I only brought it up because an architect friend of mine spotted it and I started researching. The builder definitely used Tyvek in his most recent build before mine (I have pictures) and possibly other ones.

I am also concerned about the way the flashing was installed. There is flashing tape around all 4 sides of the windows. Apparently the WRB should be laid over the top as a flap and this is not what was done in my case. I am going to look into this as well.

Thanks again,
CJ

Well, I assume your contract didn’t specify such things.....as long as they are not specified and he meets code, you’ll have to pay extra if you want something different.  In this case, now that’s it up, you’ll have to pay for removal and replacement if you want it changed.

@Chris Jargens

Many good systems out there but you really need to look at the product data sheets to compare #'s.  Some products are water resistive barrier (wrb is what I assume you mean)  and some products are just air barriers.    You also need to look at the product installation instructions for the openings.  If the contractor put up the WRB then the windows and then flashed with tap, you probably got a really good install.  Windows are a b-itch to flash.  I have tried this at a seminar with using 5 different mfrs and products. Liquid applied air and moisture barrier is the way to go but not common on homes I feel.   With these products your are looking at perm ratings,  will it allow vapor drive?,  will air pass thru.   These types of barriers are great.  I would be more concerned having continuous insulation on a building to stop thermal bridge.  That's a separate topic and we don't really see this on residential yet.  If using polyiso or extruded polystyrene (exp)  not expanded polystyrene) will give you an air barrier and moisture barrier if the joints are full sealed.  

Most likely contractor will be asking for more money like the others have said but if he did the bait and switch then I would refuse make him show you the other product is equal or better than tyvek. You can install tyvek over the top of the existing wrb typically.  

google "air barrier vs vapor barrier"

http://www.airbarrier.org/

Hi Jim,

Thanks for the thorough description and information. I went to the build today and noticed that the flashing at top of all the windows appears to be installed incorrectly. A flap of WRB is pulled through between the frame and head of the window. After that, flashing tape was attached horizontally over the WRB and flange. My impression from the Andersen installation guide is that a flap of WRB should be lifted up and flashing tape installed underneath this. Then the flap is laid down and taped flush.

My house looks like this.

The correct installation (according to Andersen) should look like this.

I did some digging, curiosity got to me as I mainly design masonry buildings vs wood framed. From data published on Tyvek and Typar websites I believe tyvek is more robust product.  BUT each mfr tested differently based on some of the ASTM (dates) used, thus different results.    Remember the UV limit of 4 months max (for Tyvek).  After than, rip it off and do it over at no cost to the Owner. 

Typar

Overview - http://www.typar.com/products/typar-buildingwrap/

Install - http://www.typar.com/assets/downloads/pdf/TYPAR_Weather_Protection_System_Installation_Guide_1.pdf

Tyvek

Overview - http://www.dupont.com/products-and-services/construction-materials/building-envelope-systems/articles/technical-documents.html

Install - http://www.dupont.com/content/dam/dupont/products-and-services/construction-materials/building-envelope-systems/documents/K16282-Residential-WRB-Install.pdf

All product mfrs have reps that will come and field inspect on residential with a simple phone call to the company.  Plan on a 20 min process after calling the 800 number and then connected to the local rep.   This is a FREE service the company provides. You can usually get someone on site within a weeks time.

@Chris Jargens

Yes the top pic flashing is wrong.  The windows don't concern me as much and the improper field lap 12" above the window.  Water will drain back behind the wrb! 

@Chris Jargens given the Information you provided; From a builders perspective, he meets code and your agreement. Nothing more, nothing less. Trust me when I say that code is the bare minimum and not for the highest quality construction. I’d approach this with an application, rather than a product approach. IMHO....tyvek and the other house wraps are applied as formalities rather than for performance. Unless you are jumping to the high end wraps, focus on application. Bring your Anderson info and SHOW him how you want it done. Remember, you don’t get what you expect, you get what you inspect. IMO, In the future, throw that house wrap to the curb and go with zip plywood in the future. It performs and is much less labor. Finally, why are you putting siding up AFTER the drywall has been installed? That could be a recipe for disaster with siding installers banging on the walls after your finished product is installed on the interior

Thanks for all that info Jim and Jonathan. I had a discussion with the builder and he offered to install the Tyvek homewrap in the method that Tyvek describes when AFTER the windows have already been installed as shown in Jim's links over the existing WRB this time using flat cap nails and tape. I personally think this is a reasonable compromise as there will be preexisting WRB present around the sides and bottom of the frame.

Jonathan, the siding is brick so I assume that there will be minimal banging on the walls except where the ties are involved.