Different Ridge Vent Levels - Roofing - Contractor Talk

Different Ridge Vent Levels

Thread Tools Search this Thread Display Modes
Old 02-17-2013, 01:01 PM   #1
Registered User
ksw1234's Avatar
Trade: Paint
Join Date: Feb 2013
Posts: 2
Rewards Points: 10

Different Ridge Vent Levels

I have an addition with a zig-zag ridge, 9ft ridge then a 6ft ridge after a short descent (1 foot lower ). Can't find any doc describing if the difference in heights would cause an issue if I ridge vent both of them. Same attic space. Any suggestions?
ksw1234 is offline  

Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ContractorTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!




Old 02-17-2013, 03:37 PM   #2
kubie's Avatar
Trade: general contractor
Join Date: Oct 2008
Location: Central Wisconsin
Posts: 434
Rewards Points: 278

Re: Different Ridge Vent Levels

3' difference is our rule of thumb.

any more than that, it causes a vacuum and now the ridge becomes an intake

unless its separated from the main attic space.


kubie is offline  
Old 02-18-2013, 12:17 AM   #3
CompleteW&D's Avatar
Trade: Windows, Doors, Siding, Enclosures
Join Date: May 2011
Location: Indianapolis, IN
Posts: 2,495
Rewards Points: 2,936

Re: Different Ridge Vent Levels

Originally Posted by kubie View Post
3' difference is our rule of thumb.

any more than that, it causes a vacuum and now the ridge becomes an intake

unless its separated from the main attic space.
Even at a 3' difference in height, the ends of the lower ridge vent will become intakes for the higher vents. the ONLY way to eliminate that is to block off each level of attic area.

Air is like water. It seeks a level and takes the path of least resistance to get there. A 3' height difference is not NEAR enough when you consider the free area of a ridge vent is considerably greater than most soffit vents.
- John Williams
Complete Window and Door
Originally Posted by TNTSERVICES View Post
As accomplishments go, getting me to talk is an easy one.
CompleteW&D is offline  
Sponsored Links
Old 02-18-2013, 03:03 AM   #4
Eater of sins.
ScipioAfricanus's Avatar
Trade: Designer/Drafter/General Contractor(again)
Join Date: Sep 2008
Location: Orange County, CA.
Posts: 4,274
Rewards Points: 504

Re: Different Ridge Vent Levels

Knowing as much as we do about your addition (which is to say, almost nothing) it is difficult to say anything intelligent as you have not even provided as much as a location.
You could be in the high desert of California or you could be in the frozen wasteland known commonly as Canada.

So I am going to hazard a guess and say that you will be fine putting ridge vent on both ridges and the most that might be wrong is that you wasted a little bit of time and money doing a harmless, yet slightly wasteful install of a superfluous ridge vent.

You are welcome.

ScipioAfricanus is online now  
Old 02-21-2013, 12:36 AM   #5
madrina's Avatar
Trade: roofing and other envied trades
Join Date: Feb 2013
Location: dallas
Posts: 3,028
Rewards Points: 1,280

Re: Different Ridge Vent Levels

The way I Understand it is u need intake and exhaust. Twice as much on the bottom creates a flow of air that pulls from the bottom and pushes out the top, where the hot air goes naturally. Anything in between disrupts the flo of air hence rendering the ventilation system ineffective. OR rendering the maximum potential of the system ineffective. IMO a foot difference would not make that much of a difference especially if the two levels are right next to eachother. That being said, I do know that inproper ventilation in your attic space will have an effect on the life of your shingles. As it has been mentioned in the posts above, more info or pictures could possibly aid the contractors here in determining a solution to your problem.
madrina is offline  

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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
Made in USA product list J.C. General Discussion 378 04-23-2019 05:16 AM
Ridge Vent advice power Roofing 12 01-22-2013 09:55 AM
seal gable vents after ridge vent installed? tacoma5050 Roofing 41 06-07-2012 07:32 PM
ridge vent or no ridge vent for this .... enforcer Roofing 2 02-08-2012 05:53 PM
Ridge Vent issue--- enforcer Roofing 5 04-27-2011 10:16 AM

Join Now... It's Fast and FREE!

I am a professional contractor
I am a DIY Homeowner
Drywall Talk is for

At DrywallTalk.com we cater exlusivly to professional contractors who make their living as a contractor. Knowing that many homeowners and DIYers are looking for a community to call home, we've created www.DIYChatroom.com DIY Chatroom is full of helpful advices and perfect for DIY homeowners.

Redirecing in 10 seconds
No Thanks
terms of service

Already Have an Account?