×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Exterior Sheathing for Stucco Exterior - Advanced Framing

Exterior Sheathing for Stucco Exterior - Advanced Framing

Exterior Sheathing for Stucco Exterior - Advanced Framing

(OP)
When you are using advanced framing techniques (2x6 exterior studs @ 24" oc) what exterior sheathing do you specify when you have stucco or other relatively brittle finishes? Our office standard is to use 15/32" exterior sheathing (for typical 16" of studs). This sheathing is typically installed vertically (strength axis parallel to studs).

Per SDPWS Table 3.2.1 at 24" oc spacing 15/32" (4 or 5 ply) panels are capable of spanning 24" with 40 PSF nominal capacity when installed vertically. This would translate to 25 PSF allowable wind pressure. In low wind areas (110 mph per ASCE 7-10) this would calculate out without issue. However, APA put out a document in 1996 (Installation of Stucco Exterior Finish Over Wood Structural Panel Sheathing). Here they recommend 19/32" plywood or OSB where panels are to be installed vertically. I see no mention of this requirement in their Advanced Framing Construction Guide published in 2014. I sense we will get some push back on the 5/8" plywood, but want to make sure the stucco is properly supported.

What do you all use in these situations? We could specify that the panels be installed horizontally but I suspect this would be installed incorrectly often. Additionally, if you are adding blocking at the panels joints it defeats the purpose a bit of using 24" oc stud spacing. With stucco finish, I would think you would want blocking or framing clips to support the unsupported edges to avoid cracks.

RE: Exterior Sheathing for Stucco Exterior - Advanced Framing

I've required them be installed horizontally before and there were zero issues since we brought it up in preconstruction. Check out the 2015 SDPWS. I have a feeling the spec for horizonal installation will be coming alot more as people start to use the sheathing for the new uplift provisions.

RE: Exterior Sheathing for Stucco Exterior - Advanced Framing

(OP)
With a stucco finish do you put blocking at the panel joints when sheathing is installed horizontally? If you do this, doesn't this somewhat defeat the purpose of the 24" oc stud spacing?

RE: Exterior Sheathing for Stucco Exterior - Advanced Framing

I've never had a contractor complain. And our drawings are always specifying face grain horizontal.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources