Inside corners…
user-757117
| Posted in Green Products and Materials on
Does anyone know of some kind of pre-formed adhesive “patch” for sealing “3D” inside corners?
How are inside corners sealed (taped) with the Zip sheathing system?
Pictures I’ve seen only show taping of seams on one plane… there always seems to be a shadow covering the corner work…
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Replies
Interior sheathing or Exterior?
have you looked at SIGA Details for ideas?
http://www.siga.ch/Downloads.21.0.html?&L=1
Hi Lucas,
The product that you are looking for is Corvum 30/30. It will stick to Huber Zip Panels just fine in an interior application. It is not for exterior use. For exterior applications it would be Wigluv 60 or 100. The 100 has a split back that makes corners easier. Both are available at http://www.smallplanetworkshop.com
Thanks for references guys.
The application is interior air sealing.
I am required (sigh) to include a warm side VB in my envelope.
It is my intention to detail a poly VB as my air barrier.
I have worked out many details to make this approach effective, however one nagging problem is the "3D" inside corner.
I would like to keep the sheets of poly flat with respect to each plane...
I want to avoid "poly origami".
There is always a "pin hole" in the corner.
I was imagining an adhesive "patch" that could plug "pinholes".
John, I think that is another advantage to ADA.
No trouble with "pin holes" in the corners.
Lucas,
can you describe your 2 dimensional corner seal?
are you going to build your 2nd floor partitions AP (After Poly)?
I am thinking you may not have very many 3D corners in the Poly?
why not sealant at the "Pinhole Corners"?
Is the "3d pinhole" much different than the "Pinholes" around nails and screws that penetrate the Poly?
Hi Lucas,
If you can, consider the Siga Majpell instead of poly. It's easier to work with as you apply and does have a drying potential (if that's good in your climate) with the perm rating of .68... but will not pass air. You can tape the joints with Siga Sicral and make the corners with Corvum 30/30 by pre-forming the shape you posted above. Done with some care, you'll avoid any meaningful pin holes. I've done this my self when sealing inset tilt & turn windows, corners on OSB as the interior VB and the house (Dan Whitmore's Seattle Passive House) blew less than 0.50ach. The pre-formed corners are easy to make by splitting one leg and bending 90 deg. When taking the Majpell around an inside corner you can cut the joint, staple to hang at I/S corner and tape it over the joint including staple, so as not to have a "cove" that can get punctured.
Also... Better than staples is the Siga Twinet. It's an aggressive double stick tape used to hang Majpell with no fastener penetration. Again tape the joints and it's sealed with no penetrations. This is typically done where a service cavity is used rather than GWB being applied directly over the airbarrier. The GWB fasteners being applied over the AB does tend to diminish the returns for the effort.
Good luck!
Lucas,
Have you ever used the Schluter waterproofing (shower pan) system? They make a preformed inside / outside corners for their Kerdi membrane:
http://www.schluter.com/8_1_kerdi_3965.aspx
It seems like overkill, but Kerdi-Kereck is the only preformed corner I've ever seen.
One more idea. You can make your own inside corners very easily. Origami directions:
1) Cut 4" square piece of cloth / paper / plastic.
2) Make a valley fold along the X axis, then a valley fold along the Y axis. The paper will now be divided into four equal squares.
3) Now make a cut along the -Y axis. Cut until you are just shy of the centerpoint.
4) Twist -X, -Y section to cover the X, -Y section.
Voila! It's incredibly easy (and the only method that worked well in shower pans before they started selling the seamless preformed corners).
Apply adhesive to the overlapping sections, and place a dab in the corner. You can preinstall these corners before you run the main sections of poly.
Inside corner in two pictures:
John,
Check out #13 in the "Detail directory thread".
Yes, but some partition walls on the lower floor will require poly "patches" similar to the drywall "patches" you described in the "Cross-hatching" thread.
You're right that there aren't many "pinhole corners" - unless my wife and our architect get their way with the faux "vault" in the ceiling ;-)
Possibly some "goo" in the corners will do the trick. I was just thinking that the poly might move a bit with air pressure changes and cause the "goo" to fail.
Possibly... I am going to try to install the poly in a continous sheet against the plywood sheathing with staples along the top and bottom edge only. Poly "flaps" from below and above be taped so as to overlap the stapled area.
The unstapled middle portion of the poly will be restrained against the sheathing by 2x3 furring. The furring will be fastened by a single 4" screw - through the poly and sheathing - to studs 16" OC.
My thinking is that "leakage" through these "pinholes" will be minimal with the poly being sandwiched between the furring and the sheathing and the screws being burried in the studs behind the sheathing...
Albert, thanks for the advice. I will check it out.
I am open minded about different materials - but am sometimes limited by what is available in my relatively remote location.
Daniel, thanks for the origami lesson ;-)
I like your idea.