DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Roofing/Siding (http://www.diychatroom.com/f9/)
-   -   A tiny sag noticed on roof (http://www.diychatroom.com/f9/tiny-sag-noticed-roof-190919/)

kah5683 11-24-2013 01:34 PM

A tiny sag noticed on roof
 
Bought a house a few months ago. When I was on roof this week for gutters, noticed a 2 small depressions on roof surface. When I went in attic to investigate, I saw this:

http://imageshack.com/a/img716/309/gi5k.jpg

http://imageshack.com/a/img69/3379/rmsk.jpg

http://imageshack.com/a/img855/9182/q4l0.jpg

What am I looking at here? Is this something to be dealt with immediately, or can it wait until spring (if attention is needed, of course)? Is this something I can repair on the inside by adding some piece of wood to brace?

If this can be done by a diy-er, and needs to be done now, can you please explain in a little detail to someone who can figure out, but needs a clear picture?

I have been leaning on you guys for a lot of knowledge since buying this house. I really appreciate all you do!

joecaption 11-24-2013 01:43 PM

Someone that installed that roof was sleeping or missed class the day they talked about installing H clips between the trusses or rafters.
http://tecotested.com/techtips/tt_edgeclips
To late now, now your going to have to add blocking from below to support it.
Just measure the distance between the rafters and cut a 2 X 4 that length. Tap it in place and toe nail it to the rafter.

roofermann 11-24-2013 05:29 PM

Quote:

Originally Posted by joecaption (Post 1270862)
Someone that installed that roof was sleeping or missed class the day they talked about installing H clips between the trusses or rafters.
http://tecotested.com/techtips/tt_edgeclips
To late now, now your going to have to add blocking from below to support it.
Just measure the distance between the rafters and cut a 2 X 4 that length. Tap it in place and toe nail it to the rafter.

Joe's got it, wait till it warms up to reduce the chance of cracking the shingles.:thumbsup:

ddawg16 11-24-2013 06:14 PM

2x4 rafters 24" OC? Really?

Hard to tell from the pics....but that almost looks like 3/8" plywood

joecaption 11-24-2013 06:21 PM

Hardly think lifting the shingles a 1/2" is going to do any harm.

kah5683 11-24-2013 06:35 PM

Quote:

Originally Posted by ddawg16 (Post 1270994)
2x4 rafters 24" OC? Really?

Hard to tell from the pics....but that almost looks like 3/8" plywood

House is 40 years old. Here is another pic of the attic:

http://imageshack.com/a/img822/2624/w5rv.jpg

ddawg16 11-24-2013 06:43 PM

Are those plumbing vents sticking up?

DannyT 11-24-2013 06:58 PM

looks more like the vent pipe from the bathroom fans.

roofermann 11-25-2013 03:30 AM

Quote:

Originally Posted by joecaption (Post 1270997)
Hardly think lifting the shingles a 1/2" is going to do any harm.

No idea where the guy is, could be stupid cold. No harm in leaving it til spring. Those possible bath and kitchen vents dumping in the attic are a bigger issue.:thumbsup:

747 11-25-2013 04:46 AM

When its time for a new roof. The whole roof is probably going to need new sheathing. Seeing how its 24 oc it has to be thick which isn't cheap. Stay off the roof. Do like joe said. Finally if those are exhaust vents from bathroom. Sure hope your not in a cold weather climate. The moisture from those vents could freeze on the sheathing.

kah5683 11-29-2013 01:23 PM

Yeah, those are fan vents from bathroom. Talked about it in another post. Was going to run a flexible duct to current vent in roof, but was suggested I put new hole in roof over both fans with a new vent to outside. Waiting until spring.

Unfortunately, I am in cold area - suburbs of Chicago.

joecaption 11-29-2013 03:31 PM

24" on center is common, but there should have been thicker sheathing and H clips in a snow area.

Gary in WA 11-30-2013 03:00 PM

Take another picture of an ink stamp on one sheet for us, please. The plywood used may be code-approved for the application. H-clips may/not be required, depends on the rating given on the stamp; http://www.strongtie.com/products/co...pscl-psca.asp#

Code is similar; http://publicecodes.cyberregs.com/ic...?bu2=undefined

Center support on 24" is always good even on rated for the span applications. IMO, the one edge went opposite the other due to expansion from humidity and was not gaped 1/8" at edges at application. The fasteners hold the sheet stationary, the edges can't move toward each other so they move in elevation. If the sheathing is tight- no gaps- during the summer, the blocking may only even the two edges temporarily until humidity (seasons) changes again. Solution is to remove material from one sheet for a proper/required gap. (OR) The extra moisture from the fans is causing the buckling, fix that ASAP and the sheathing may shrink down flush alone (don't add a block until ply is dry). Next comes mildew (mold) after the ventilation can't keep up with moisture you are forcing against the wood sheathing. The 1/2" three-ply plywood looks similar to yours, though we can sit here and guess all day....... need a pic.

Gary


All times are GMT -5. The time now is 07:49 PM.