Ridge Cap Venting Issues - Poor Ventilation??

askeyb · 02-05-2013, 12:12 AM

I had my roof replaced 2003. I was told ridge cap venting is really good and will help keep the house cooler during summer. Paid extra for it. The ridge cap had to be replaced within a couple years. Then in 2008 we noticed moisture. Contractor came out and attic was full of moisture and plywood destroyed. We were told that adequate venting along the eves was the problem. Previous owner must of had insulation blown into the attic and covered some of the vents. My wife and I unplugged all the vents. I was also asked to put humidity thermostats on the attic fans on both ends of the roof. I did that and the problems were determined resolved. A new roof was installed on warranty replacing all the plywood and ridge cap venting was installed again.

Within a few weeks of install we got warm weather at about 70 degrees and the attic fans ran. This happened several times so I called the contractor back. I told him that was really unusual and never had the fans come on till it got hot 80 to 90 degrees. I was told everything is to code and should be good. I still asked why is it doing this?? That was 2008.

I haven't looked in the attic for some time figuring it is all working fine. Well recently one attic fan comes on and stays on for 24 hours. After a couple hours of it running I got a ladder and removed the attic access panel. Got a light and was very displeased with the attic. It is all wet with moisture and mold.

I had a roofer working on a local house come look at it. He told me they don't recommend ridge cap venting and have seen a lot of houses with the same problem. Also with attic fans they should of never installed the ridge cap venting. The roofer told me this roof is in really bad shape and needs to be replaced real soon. He said it is a real health risk. He advised me to get the person who installed it out and fix it right or get an attorney to go after them.

The original roof did not have moisture issues of any kind. The original roof had the conventional metal mushroom shaped vents. The roofer told me the Ridge Cap venting is not working and he could feel warm heat in the attic which tells him it is not ventilating properly. Also ridge cap venting gets build up on it that eventually blocks air flow. He agreed if I already had an issue with the attic fans coming on with mildly warm weather then it must of not been properly ventilating since installed.

Now I have to try to get the company that replaced the roof a second time in 2008 to replace it again due to improper install of ridge cap venting. I can't see anything else causing this problem. All the eve vents are open as requested prior to replacing the roof in 2008. The only other possible reason is the ridge cap venting not letting the roof breath properly.

joecaption · 02-05-2013, 01:50 AM

What type ridge did they install?
If it's Cobra vent then that's part of your problum.
There worthless.
How far did they open up the roof at the peak?
A ridge vent is useless if you also have gable vents or any other type venting.
Those power vents should have been removed when the ridge went on.
All those power vents are just drawing in air from the ridge vents not from the soffits.
It would be nice to see a picture of the soffit vents you have now.
The attic should have been air sealed any place there's ceiling lights, or fans, any place wiring or plumbing was run through the top plates.
There should have been baffles to keep the soffit vents clear of insulation.

Sure you have enough insulation up there?
http://www.energystar.gov/index.cfm?...sulation_table

askeyb · 02-05-2013, 03:10 AM

What tryp ridge did they install?

Askeyb: I am not sure. It was the third ridge cap venting. It has a scotch pad looking black material. Roofing was installed over it.

If it's Cobra vent then that's part of your problum.
There worthless.
How far did they open up the roof at the peak?

askeyb: I think a couple inches on each side.

A ridge vent is useless if you also have gable vents or any other type venting.

askeyb: The roofer today told me they should of never installed ridge cap venting with the fans already installed on the roof. The contractor that did the roof even had me buy humidity thermostats for the fans so I would be protected against heat or moisture. The fans never came on till recently and last week ran for almost 24 hours and again today for about 10 minutes.

Those power vents should have been removed when the ridge went on.
All those power vents are just drawing in air from the ridge vents not from the soffits.
It would be nice to see a picture of the soffit vents you have now.
The attic should have been air sealed any place there's ceiling lights, or fans, any place wiring or plumbing was run through the top plates.
There should have been baffles to keep the soffit vents clear of insulation.

askeyb: one of the previous owners had insulation blown into the attic and they didn't put card board barriers in to block insulation from covering the eve vents or suffits. My wife and I went around the house blowing out the suffits. The one area I had to go into the attic and remove wood that had been placed over the suffits. Interesting is that the original roof did not have a moisture problem even with what was found. The contractor blamed the problem in 2008 to the suffits and suffits that had been covered. The contractor had holes drilled and round vents installed for more ventilation. I was told that those little round vents are worthless.

Another issue I was told is wrong is a mushroom vent was used on the roof for the bath room vent. The vent hose is wired to the struts and pointed into the vent. Contractor told me that a round vent that the hose clamps to should of been installed.

Sure you have enough insulation up there?

askeyb: I believe I do have enough insulation but more would probably be better. The current blown in installation is as deep and a little over the framing on the bottom of the attic. You can still see where to place your foot when in the attic and it looks pretty deep. I would describe the material as looking like worm bedding.

Attached is a picture I took today. You can see the ridge cap venting material, black at top. You can see the mold in the plywood. And the sky lite with nothing around it. The vent to the bath room is barely visible but you can see the open vent on the left side of the picture.

http://www.energystar.gov/index.cfm?...sulation_table[/QUOTE]

joecaption · 02-05-2013, 03:50 AM

That style vent is so bad all my supplyers have stopped selling it.
http://www.airvent.com/pdf/literature/PAVbooklet.pdf

jagans · 02-05-2013, 09:52 AM

1. There are no wide angle pictures of your house so we can see the roof construction, or type of roof installed.
2. You do not say where you are from, or what the mean temperatures are.
3. You dont say what type of insulation or what R-Value you have.
4. There are no close ups of the ridge or the eaves.

You do say you have Cobra, which is worse than nothing, as it increases the chance of ridge cap blow-off.

I do see the fan you have installed. That might make a marginal difference in a dog house, based on its size.

By the way. are you venting a clothes dryer into your attic?

Instead of having people pull the answers out of you one at a time, and speculating what is wrong, do you think you could just post some pictures, and relevant information?

askeyb · 02-05-2013, 02:26 PM

I live 30 miles south of Portland, Oregon in what is called the Willamette Valley.

Temp winter seems to be around 35 to 40. Wet rainny winter with snow a couple times each year.

I really don't know the insulation R-Value. The main house is a blown in material that seems fairly deep. Looks like worm bedding.

Over the room that use to be a garage is a false ceiling with think layers of insulation. Some areas are over lapping so double layer.

The bathroom vent is the only vent going through the attic. The contractor didn't install a vent that the vent hose connects to. The bath room vent hose is wired to the struts end slightly into the vent. I was told that is not good.

Attached are six pictures. Let me know if these show you what you need to see.

1. There are no wide angle pictures of your house so we can see the roof construction, or type of roof installed.
2. You do not say where you are from, or what the mean temperatures are.
3. You dont say what type of insulation or what R-Value you have.
4. There are no close ups of the ridge or the eaves.

You do say you have Cobra, which is worse than nothing, as it increases the chance of ridge cap blow-off.

I do see the fan you have installed. That might make a marginal difference in a dog house, based on its size.

By the way. are you venting a clothes dryer into your attic?

Instead of having people pull the answers out of you one at a time, and speculating what is wrong, do you think you could just post some pictures, and relevant information?[/QUOTE]

jagans · 02-05-2013, 02:53 PM

Looks like your neighbors have the same setup. Do they have problems? Looks like you have a lot of green mold on the sheathing over by what appears to be a triple wall flue stack, and Im not getting that ridge cap at all with what appears to be foam between ridge caps.

It appears that you do have a severe lack of through ventilation in the attic space

askeyb · 02-05-2013, 04:11 PM

Looks like your neighbors have the same setup. Do they have problems? Looks like you have a lot of green mold on the sheathing over by what appears to be a triple wall flue stack, and Im not getting that ridge cap at all with what appears to be foam between ridge caps.

It appears that you do have a severe lack of through ventilation in the attic space.

askeyb:That is what I have decided. also right after install the attic fans run if we get 70 degree weather. I did call about that and nothing was done or checked.

We are the only house with ridge cap venting in the neighborhood. no one else is having mjoisture isses.

Does the eve venting look ok? They did add those round vents.

HomeSealed · 02-05-2013, 04:15 PM

Are those little holes the only venting that you have in the soffit? To me it looks like a combination of lack of ventilation + lack of air-sealing and that bathroom exhaust being improperly ducted. Certainly you want any warm, moist air that gets into the attic to be moved out, however you really want to keep that warm air from leaving your conditioned living space in the first place.

askeyb · 02-05-2013, 04:31 PM

Are those little holes the only venting that you have in the soffit? To me it looks like a combination of lack of ventilation + lack of air-sealing and that bathroom exhaust being improperly ducted. Certainly you want any warm, moist air that gets into the attic to be moved out, however you really want to keep that warm air from leaving your conditioned living space in the first place.

Askeyb: The original suffit vents are the slotted with screen. The contractor added the round vents after the roof was installed. The plan which I didn't know and if told would of made sure got done, was that as the plywood was removed a pre-screened 2x4 was supposed to replace some of the suffits that were not vented between the struts. The contractor didn't check till after the job was done.

I believe the problem as decribed to me is that moisture and warm air is trapped in the attic. Being that the ridge cap venting never did work correctly and also had attic fans and vents should of never been installed. I was told it was the greatest way to go and it has been a headache ever since being installed. Each time the ridge cap was replaced I was told this will work and it hasn't.

PatChap · 02-05-2013, 05:01 PM

Looks to me like they over compressed the ridge vent, possibly gun nailed a vent that was meant to be hand nailed. I've also seen this happen if guys sit on the ridge while they cap it. That style of vent does work, it just isn't as good as a plastic one, more likely to clog.

**Gary in WA** · 02-05-2013, 11:50 PM

How uniformly will the roof be ventilated by a given product? Will some roof areas or rafter bays be left un-vented?

Looking at a linear foot of a typical thick mesh-type ridge vent and before considering that power-nailing compresses the mesh to further reduce airflow: From; http://www.inspectapedia.com/interiors/atticcond10.htm

The 3- 2" circular soffit vents supply 2.5 NFVA for all three. lol. That is about 1/3 of what you need, if they were not painted shut. The slot vent is about 1"x16" ? for about 13NFVA if it was not blocked by the fiberglass, as pictured. Figure your requirements: http://www.airvent.com/homeowner/pro...it-specs.shtml

http://www.blocktheheat.com/ventproblems.htm

Gary
PS. you have an excessive moisture problem and ineffective venting, find the source...

joecaption · 02-06-2013, 09:02 AM

Those small round vents are doing next to nothing being that close to the area that should have been covered with insulation, the venting needed to be in the soffits.
http://www.bing.com/images/search?q=...electedIndex=8

http://www.bing.com/images/search?q=...electedIndex=7

PAHome · 02-06-2013, 09:46 AM

I wish you the best of luck, below is a link that will explain why you should not mix a power vent and a ridge-vent.

http://www.airvent.com/pdf/literatur...nstallTips.pdf

www.pa-homeimprovements.com
PA Home Improvements Inc.
764 North 9th Street
Stroudsburg PA 18360
"your local roofing experts"
570-484-ROOF

HomeSealed · 02-06-2013, 10:47 AM

Quote:

Originally Posted by askeyb

I believe the problem as decribed to me is that moisture and warm air is trapped in the attic. Being that the ridge cap venting never did work correctly and also had attic fans and vents should of never been installed.

Correct... Joe, Gary and myself have all also identified the fact that you can and should mitigate the warm, moist air in there by fixing the source (heat loss from the conditioned living space/improperly vented exhaust fan), in addition to getting the venting taken care of.