Thread: Reason for rotten roof decking??

I found a water damaged area in the attic next to a dormer (see picture). Upon inspection of the roof in the suspected area, all I could determine was that the dormer was not flashed correctly (see picture). What do you think?

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Shouldn't the flashing come out on top of the shingles along the bottom edge of the dormer?

Yes, a proper flashing would go up under the vinyl siding and come out on top of the shingles. My guess is that the white flashing wall is supposed to be a water stop. I wouldn't be surprised if that is acting like a dam and keeping enough water up there in heavy rains to penetrate the valley. Needs proper repair.

Most likely a flashing issue, in fact I don't see any flashing.

I would report that I found rotted decking under the dormer and that it is most likely associated with improper flashing. Then I would simply say that it needs to be properly repaired so that it will not happen again.

Yes, you need to be able to see the flashing....

Originally Posted by Scott Patterson

Then I would simply say that it needs to be properly repaired so that it will not happen again.

This is worth repeating.... Always go for performance based recommendations when possible. If you get too caught up telling them exactly how to fix it you'll buy it if you're wrong. Or, even if you're right and someone disagrees with you. In any case, you make your life a lot easier by not going down the 'designing repairs' road too far.

Don't forget about the overlapping shingles below that dormer.

Yup it's wrong

and i bet most contractors or realtors won't agree with you

I see it often

besides Dormers are usually eyesores

Originally Posted by Joe Laurieri

Yup it's wrong

and i bet most contractors or realtors won't agree with you

I see it often

besides Dormers are usually eyesores

It doesn't matter if the realtor agrees with you or not. There is how it was done (incorrectly with the flashing - if any - running under the shingles), how it should have been done (with the flashing under the siding and on top of the shingles), and the consequences (water infiltration and rot).

Call a Closed Cut Valley. What makes it unaceptable? If it is a Closed-cut California Valley it is acceptable on slopes of 4/12 or greater. Just wondering.

Originally Posted by Terry Acra

Call a Closed Cut Valley. What makes it unaceptable? If it is a Closed-cut California Valley it is acceptable on slopes of 4/12 or greater. Just wondering.

It's not the closed-cut valley that's wrong, it's the flashing (or lack thereof) at the dormer that is unacceptable.

If we're getting technical here, the closed cut valley is wrong also according to nearly 100% of shingle manufactuerers. Look at any package of shingles and the diagram and instrcutions will clearly state the proper way, again per mfg's. recommended installation instrcutions, to install a closed cut valley. This includes running the seam out of the valley (2") vs. right down the center. Not visible in the photo's but also recommended is "dubbing" or "clipping" the shingle corners that are overlapped to help direct water into the valley and not (if pointed and not dubbed) under the shigles along the top edge of the overlapped shingle.

Bill

Originally Posted by Shawn Watkins

I found a water damaged area in the attic next to a dormer (see picture). Upon inspection of the roof in the suspected area, all I could determine was that the dormer was not flashed correctly (see picture). What do you think?

You ask a question. That I don't think you understood just what you were asking.

What you have in these photos in not water damage or rotten wood.

The term is ( FUNGUS DAMAGE ) Water, wood, air and temp are all parts of life. and life being ( FUNGUS ). Its the fungus that eats the wood.

So when you have a roof leak you are now providing the one missing element of life. for ( FUNGUS ) to grow and eat the wood. You can have delimitation of some boards. like press boards but most of the time its a fungi.

Best

Ron

Ron

Wood can become rotton, damaged, or whatever term you chose without fungus. Although fungus is almost always present in does not cause all the damage to wood subjected to moistue.

Originally Posted by Stacey Van Houtan

Ron

Wood can become rotton, damaged, or whatever term you chose without fungus. Although fungus is almost always present in does not cause all the damage to wood subjected to moistue.

Hey Stacey. If you use the term Rotten then it is ( FUNGUS ) that has done the damage or rotted the board. Thats what a (WDO is). (Wood destroying organism ) Water damage is like Delamination you can find in press boards. We see this under a lot of kitchen/bathroom cabinet sinks.

Moisture damage = Delamination Only in press boards.
if you ad a ( fungi ) you now have ( FUNGUS DAMAGE )

If moisture could damage a board then we would not find logs that have been at the bottom of lakes for hundreds of years that are in perfect condition.
this is because there was no air. to ad to the other parts of life.

Food+air+water+temp = Life = ( fungus ) WDO.

Hope this helps

Best

Ron

Originally Posted by Ron Bibler

Hey Stacey. If you use the term Rotten then it is ( FUNGUS ) that has done the damage or rotted the board. Thats what a (WDO is). (Wood destroying organism ) Water damage is like Delamination you can find in press boards. We see this under a lot of kitchen/bathroom cabinet sinks.

Moisture damage = Delamination Only in press boards.
if you ad a ( fungi ) you now have ( FUNGUS DAMAGE )

If moisture could damage a board then we would not find logs that have been at the bottom of lakes for hundreds of years that are in perfect condition.
this is because there was no air. to ad to the other parts of life.

Food+air+water+temp = Life = ( fungus ) WDO.

And, without water in your equation there would be no life, thus water created the condition which caused the damage (without that water = no damage).

Besides, "If you use the term Rotten then it is ( FUNGUS ) that has done the damage or rotted the board. Thats what a (WDO is). (Wood destroying organism )" WDO *does not* = "rotted".

Originally Posted by Jerry Peck

And, without water in your equation there would be no life, thus water created the condition which caused the damage (without that water = no damage).

Besides, "If you use the term Rotten then it is ( FUNGUS ) that has done the damage or rotted the board. Thats what a (WDO is). (Wood destroying organism )" WDO *does not* = "rotted".

You can have water, Air. and a temp of 20degrees and you will not have damage.

You can have a temp of 120degrees air and no water and you will not have damage.

But if you have a temp of 60degrees to around 105 degrees then ad water. with air and a board. and still not have damage. you need the fungi.

with a little wind the air will provide the fungi. and now we have all the condition for life=( fungus damage ) or as some may say ( DRY-ROT )

Best

Ron

That first picture of the attic view looks like the bottom of the valley at the fascia. Not the dormer. Bill B. must be a roofer. Clip the corners would only be know to us. Funny though siding installers should also be clipping the points off panels along roof walls back in the day when they ran hard board panels.

Sorry guys but you are WRONG

Wood (not engineered wood) will undergo a damage on a ceullar level as it becomes wet and then dry. As this process ocurres over and over the ligin in the cell wall breaks down. Some in the past have called this dryrot to try to seperate it from rot caused by fungus.

This is old science and not my opinion but fact.

As I said usually both events are occuring fungial attack and destruction from expansion and contraction.

Originally Posted by Stacey Van Houtan

Sorry guys but you are WRONG

Wood (not engineered wood) will undergo a damage on a ceullar level as it becomes wet and then dry. As this process ocurres over and over the ligin in the cell wall breaks down. Some in the past have called this dryrot to try to seperate it from rot caused by fungus.

This is old science and not my opinion but fact.

As I said usually both events are occuring fungial attack and destruction from expansion and contraction.

So what would be the most common casue of damage to wood.

A fungi damage ?

Or As you stated. will undergo a damage on a ceullar level as it becomes wet and then dry?

And how will we known what to call during and inspection. As one is from a WDO.( FUNGI ) And must be listed on an FHA Report.

And the other YOU STATED is not a WDO. And because it is not a WDO it can not be listed on a WDO FHA. Report.

As a 30 year Ca. state lic. WDO Inspector I Would like to understand more of this kind of wood damage you are pointing out. If I were to call out in one of my state reports some kind of a wood rot that has no FUNGI. The structural pest control board would eat me alive.

Best

Ron

Originally Posted by Stacey Van Houtan

will undergo a damage on a ceullar level as it becomes wet and then dry. As this process ocurres over and over the ligin in the cell wall breaks down. Some in the past have called this dryrot to try to seperate it from rot caused by fungus.

This is old science and not my opinion but fact.

Please post your information on this type of damage you are talking about.

Best

Ron

Originally Posted by Ron Bibler

Please post your information on this type of damage you are talking about.

Best

Ron

I have no info, but I can come up with an example - old cedar shingles will develop cracks and eventuallly split apart. They are not always rotten in the normal sense of the word, just weather damaged. The cell structure is broken down by wetting and drying.

Originally Posted by John Kogel

I have no info, but I can come up with an example - old cedar shingles will develop cracks and eventuallly split apart. They are not always rotten in the normal sense of the word, just weather damaged. The cell structure is broken down by wetting and drying.

Please provide information of a wet/dry damage...

I have look at this stuff for more then 30 years. and this is the first time i have ever had some one present a wet/dry damage other then a fungus.

I have been to college course to CED. Calif. State test for lic.

Not one word to support this information.

Please provide support information of wet/dry damage...

Best

Ron

Ron your are correct WDO is fungus or any thing alive that eats a home.

But as i said almost many times there is a damage from moisture at a mechanical level. I the wood industry it is sometimes called degrading if it happens pre-mill other name post-mill

Read the attached pdf.

Originally Posted by Mike Schulz

That first picture of the attic view looks like the bottom of the valley at the fascia. Not the dormer. Bill B. must be a roofer. Clip the corners would only be know to us. Funny though siding installers should also be clipping the points off panels along roof walls back in the day when they ran hard board panels.

I agree, I believe that is soffit we are seeing in the pic. You can also notice the closed valley is cut right in the center of the valley, it should be cut a few inches up from center and slightly tapered. Being cut too close to center could be pulling water into the valley.

I have also seen flashing with a shingle glued to the top of the flashing with the flashing over the top of the underlying shingle. This is usually done for appearance (to hide the flashing) and I don't see a problem with that method as long as the flashing covers the underlying shingle.

Originally Posted by Stacey Van Houtan

Ron your are correct WDO is fungus or any thing alive that eats a home.

But as i said almost many times there is a damage from moisture at a mechanical level. I the wood industry it is sometimes called degrading if it happens pre-mill other name post-mill

Read the attached pdf.

Thanks for posting that information Stacey.. I have look at that information before in a course at UC.BERKELEY... The study of entomology...

Checking/splitting is a type of damage that will damage wood. But this type of damage would never be ID As the type of damage in the original post.
What he is showing in the original photos is a Fungus Damage from a Fungi. Not from any drying or hydration of water.

I understand what you are saying Stacey and you are correct in that this is occurring in any degeneration of a wood. But to state that Jerry and I were wrong is incorrect. This post and the photos we are looking at are 99.99% fungus infection/Fungi Damage and very little wet/dry damage.

You would be best to say that there is one other type of damage occurring in these photos and then point out the wet/dry factor.

But to come out and say that Jerry and I were off base 100% is not correct.

Best

Ron

Ron
re-read your post

You said this is only fungal damage

I still disagree and the damate is moisture and fungal damage

This is, in a real would sense,f not a big deal to a degree. At least in many part of the US

We don't do WDO inspections we do WDI and so our exact wording of moisture damage to wood that has no WDI damage would be less important in my area.

Originally Posted by Stacey Van Houtan

Ron
re-read your post

You said this is only fungal damage

I still disagree and the damate is moisture and fungal damage

This is, in a real would sense,f not a big deal to a degree. At least in many part of the US

We don't do WDO inspections we do WDI and so our exact wording of moisture damage to wood that has no WDI damage would be less important in my area.

Stacey this is the point of this post. what is the problem and the proper ID. In your area and all over the US. People buy homes under FHA Type loans and on these form the pest inspector must make a correct ID If there is a WDO on the property or he/she would be in big STUFF... If you want to stick with your point of view thats ok with me. but please understand that other young inspectors look at these post and need the information to be correct. I'm not going to get into a pissing match over this issue. But you can not go around saying other inspector are off base and incorrect with an ID And not back it up.
The photos in this post are from a WDO Fungi Damage not from a wet/dry factor. This is not a 99% wet/day damage.

Best

Ron

The volume of water hitting that splash guard on the top of the gutter is shooting it back into the fascia and up under the shingles or incorrect install by means of sealant, exposed nail, nail to close to center of valley, idiot face drove a nail or roofer error. Check that area and you will find the culprit.

Ron

NMPA -33
The form we use in KC is a WDI

The is the FHA approved form

not a WDO

Yes you young inspectors reading Belive or not

If you report the attic pictures in the FHA approved WDI Report in my area you will be in a lawsuite

The left coast is not the majorty of the US

And I agree agree with you that most of the damage is WDO (fungus)

Get a "Qualified Roofer" ... they are out there, to fix it. From the pictures there are problems with both, the valley detail and the dormer detail, as the step flashing at the side of the dormer should extend past the wall flashing at the front. The trim board may be damming water at a vulnerable point.

Frank Suchodolski, RRO