Installation Of Natural Passive Vents - Roofing/Siding - DIY Home Improvement | DIYChatroom

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


Thread Tools Display Modes
Old 08-18-2010, 10:51 PM   #1
Join Date: Jun 2010
Posts: 42
Rewards Points: 25

installation of natural passive vents

I just realized that I might have made an error on the installation of passive vents on my roof. I used 4 round passive vents with 144nfa for an attic that has 2500 square feet. I followed the calculations of the OC web site; soffit nfa appropriately corresponds to the 4 passive vents. However, I did not alter the openings of the old vents; they are 8" X 9" rectangles. I just noticed the instructions for the new passive vents state that there should be a 14" diameter in the cut out in the roof. That comes to 153 square inches compare to my 72 square inches.

should I do anything"? right now at 11:43 PM it is close to 100% humidity outside the house (weather report says 100% but it isn't raining) and according to my humidity reader in the attic it is only 44% (I closed the staircase, left the reader in the attic for several hours and just returned to read it; the reader gives me approximately the same readings as a downstairs dehumidifier that I have so I expect it is quite accurate). I will monitor over the next day. The last time I checked the temperature it was 89 degrees outside and 85 in the arttic. right now it is just a little cooler in the attic than outsider. Seems to be pretty moderate in all of this, so shoudl i do anything to correct the situation.

My roof is all in (except for some trim pieces on the ridge; I ran out). No leaks; looks professional and beautiful. But , if I do have to correct the opening can i cut it larger from insider the attic. What should I do at this point?


Last edited by Alto; 08-18-2010 at 10:57 PM.
Alto 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
ridge vents vs. box vents vs. turbine vents redaws Roofing/Siding 12 03-12-2012 09:48 PM
Atic: Adding Intake and Exhaust Vents (Maybe Ridge) arcane Roofing/Siding 9 07-22-2010 06:20 PM
Ridge vents and roof vents jerry1967 Roofing/Siding 4 06-07-2010 05:40 PM
New Natural gas installation, many questions f4urak Plumbing 1 10-13-2009 11:13 PM
Electricl Installation for Electric Tankless Water Heater Educator Electrical 13 07-06-2008 10:27 AM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1