Drywall Cracking Under Snow Load - Roofing/Siding - DIY Home Improvement | DIYChatroom

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Roofing/Siding


Thread Tools Display Modes
Old 12-20-2013, 08:17 PM   #16
Join Date: Oct 2012
Posts: 11
Rewards Points: 14

Drywall Cracking Under Snow Load

Gary or others - any input on the collar tie installation height to best help with these issues?


bheemsoth is offline   Reply With Quote
Old 12-21-2013, 04:26 AM   #17
DIY staff

Join Date: Sep 2009
Location: Kane county,Illinois
Posts: 24,361
Rewards Points: 7,244

Drywall Cracking Under Snow Load

You need an answer from a framer---I suggest you start a framing thread---the carpenters seldom look into this forum---Mike----
New members: Adding your location to your profile helps in many ways.--M--
oh'mike is offline   Reply With Quote
Old 12-21-2013, 06:23 AM   #18
Civil Engineer
Join Date: Mar 2009
Location: Boston
Posts: 4,734
Rewards Points: 3,048

Drywall Cracking Under Snow Load

Collar ties are normally installed 1/3 of the way down from the peak to the joist, as Oh Mike previously indicated. The purpose of collar ties is to equalize uplift pressure on the roof during high wind events, so they are not likely to improve your particular problem, but they are supposed to be installed, and they won't hurt anything.
Daniel Holzman is offline   Reply With Quote
The Following User Says Thank You to Daniel Holzman For This Useful Post:
oh'mike (12-21-2013)
Old 12-21-2013, 09:46 PM   #19
Registered User
Join Date: Mar 2009
Posts: 10,715
Rewards Points: 3,496

Drywall Cracking Under Snow Load

Sounds a lot like this, from David Utterback; "
Rafter ties do not have to be at ceiling height to be effective, but they must not be placed any higher than the lower third of the roof pitch. In other words: Measure vertically from the outside wall's top plate to the bottom of the ridge, and place the rafter ties within the lower third of that measurement. Once they get above that point, they lose their most effective leverage.
I've seen builders compound their mistakes when they try to use rafter ties as ceiling joists in semivaulted ceilings. For maximum headroom or aesthetic balance, they place the rafter ties halfway up the roof pitch, near the center of the rafter span where they're too high to be an effective tie. Applying the insulation and the drywall greatly increases the load on the rafters at their most critical point: midspan (what engineers call the maximum bending moment). This added load can cause the rafters to sag, pulling the ridge down and also pushing the exterior walls outward." From; http://myconco.com/ComEngProb.html

I doubt they used any bolts on the rafter/joist connection; pp.7; https://docs.google.com/viewer?a=v&q...WvZygC-vGi-JoA

As in Fig. 10A, but the joist are rafter ties; https://docs.google.com/viewer?a=v&q...RMyCq7zQ737mAg

They may have put them too high, measure the height of the ceiling to top of a window inside; go outside and measure the window to top of wall or soffit block- if soffit isn't dropped.

PS. My post 5 on collar ties....
If any ads are present below my answer or words underlined/colored, I do not condone/support/use the product or services listed/linked to, they are there without my consent.
WELCOME to the forums, if I forgot to say it!
Gary in WA is offline   Reply With Quote
Old 12-22-2013, 12:06 PM   #20
Join Date: Dec 2013
Location: CoastalME
Posts: 155
Rewards Points: 151

Drywall Cracking Under Snow Load

Retaping isn't going to help. The drywall should have been floated both sides of those cracks you're seeing to minimize cracking, but some framing issue is behind it all.


eandjsdad is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Garage Header cardsman Building & Construction 16 03-06-2012 06:51 PM
The CELLAR gbwillner Project Showcase 112 02-17-2012 10:00 PM
Drywall Damage After Wallpaper Removal katega Drywall & Plaster 1 01-28-2012 10:11 PM
Drywall joints cracking and bulging in attic conversion Leroyb86 Drywall & Plaster 10 10-06-2010 01:47 PM
Adding a snow supporting arbor snmhanson Building & Construction 2 12-15-2006 06:21 PM

Top of Page | View New Posts