Attic Venting and Roofing Questions

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joesxm3

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It is coming time to have my roof redone. I have several issues that I would like to try to address if possible.

The design of my attic is not right. There are not soffits and consequently no soffit vents. Before the last roofing in 1989, there was only a 2.5 x 2.5 square with an attic fan on one gable and a smaller opening on the other gable. The attic had gotten very hot and a lot of the decking had delaminated.

The roofers in 1989 put a ridge vent on the top. I realize that this is not right since the gable fan will draw air in from the ridge vent instead of letting hot air rise out.

My house is made up of the original part, plus and addition bedroom over den part.

Since it seemed to not have enough intake area, I thought it would be a good idea to pull down the attic stairs to allow air to flow up to the attic through the stair opening.

I went up there today to check for leaks and saw that the decking on the north side of the roof is black, probably mold. I don't think it is from any leaking. However, the lower four or six feet of the plywood is ok. That is covered by ice and water shield under the shingles.

I think that what has happened is that by opening the stairs, in the middle of the attic (on the original side) I created an air flow that blocked off any air that would come in from the small gable vent on the addition side. Maybe some moisture condensed on the colder north side and made the mold.

I only open the stairs in the summer when it is really hot.

I have two layers of pink insulation properly installed on the floor of the attic. That is moisture barrier down on the bottom layer and no moisture barrier on the top layer.

So, that is the current situation. Any thoughts?
 
A while ago I saw a product that tries to mitigate the lack of soffit vents by installing a vent in the bottom six inches of the roof decking. I think if I did that all along the roof edges it might provide enough intake to just have a passive system using the ridge vent.

I am not sure if I can find someone to do that system.

I had another thought of putting two mushroom roof fans, one one each part of the attic. That way I could have air coming in through the gable vents and maybe add a little more gable venting. I am not sure if these fans would pull air backwards through the ridge vent as is probably happening now with the gable fan.

When I do the roof repair, I plan to have them remove the old shingles and replace any of the decking that is delaminating or had the black mold on it.

I also have a bathroom with two old sky lights. The sky lights open, but I never open them. Would it be OK to just replace them with sky lights that do not open?

If I do the mushroom fans, I think I will put them on the north side so I have the option of putting solar panels on the south side.

Any ideas on this stuff?

Thanks.
 
When I bought my current house they put a new roof on and fixed the decking. What they didnt catch was that the new sofit that was put on by the original owners was not done correctly in that they put in plywood to give them something to attach it to, without cutting out the vent holes.


Fast forward to the next summer and by mid-summer my decking was buckling and warping due to the heat in the attic that could not escape. What I ended up doing was having the decking replaced on the front, new roof on that again, and installed 5 solar blasters that constantly pull air out of the attic and create that ventilation. Its been two summers since then and that seems to have done the trick.
 
I found a few articles that seem to address these issues. I think the product I was describing earlier for the bottom edge of the roof is called a "drip edge vent". They go under the shingles and allow air to enter a slot about six inches from the edge of the roof.

They talk about a similar thing called an "eyebrow vent" that seems to go onto an existing roof but I am not clear on that.
 
euro said:
I would put in soffit vents if at all possible. Have to make sure that the insulation is not in the way but there are "foam tunnels" specially made for that.

https://www.thisoldhouse.com/heating-cooling/21017397/improving-attic-ventilation
Click to expand...

Thanks for the link. But I think to do what they describe I need to have soffits, which I do not have. I suppose I can do something similar with the drip edge vents or eyebrow vents that I saw in another article.

Of course that implies I can find a contractor that can understand that stuff.
 
What is a solar blaster? And how did you handle getting enough intake for the blaster to pull the air through. Did you recut the soffit vent holes?

Jeffman52 said:
When I bought my current house they put a new roof on and fixed the decking. What they didnt catch was that the new sofit that was put on by the original owners was not done correctly in that they put in plywood to give them something to attach it to, without cutting out the vent holes.


Fast forward to the next summer and by mid-summer my decking was buckling and warping due to the heat in the attic that could not escape. What I ended up doing was having the decking replaced on the front, new roof on that again, and installed 5 solar blasters that constantly pull air out of the attic and create that ventilation. Its been two summers since then and that seems to have done the trick.
Click to expand...
 
joesxm3 said:
Thanks. What keeps the rain from going down the vents?
Click to expand...


They are on the roof slope, not the peak, so I guess it would have to blow rain sideways pretty hard to get in there. Maybe their site can help, I just wrote the fat check.
 
joesxm3 said:
.....I went up there today to check for leaks and saw that the decking on the north side of the roof is black, probably mold. I don't think it is from any leaking. However, the lower four or six feet of the plywood is ok. That is covered by ice and water shield under the shingles.?
Click to expand...
If you have an ice and water shield, you probably are in an area that you can get ice dams. I would think the last thing you would want to do is to cut any openings into the shield area!

I'm missing your "no soffits" configuration. A pic would help. In the midwest, I would occasionally see two types of "no soffit" pitched roofs.

One was a cheap (I think they looked awful!) construction where the rafters literally end at the outside wall's top plate. There was no roof overhang at all. Gutters were attached to the fascia board which closed off the ends of the rafters. These houses were more prone to leaks, and I think they looked like crap with their sawed-off appearance.

The other type, were normal pitched roof overhangs, but instead of a soffit being created by 2x4s running from side of rafters back to house wall so a soffit could be attached, were open rafters instead. A wood block was nailed between each rafter at the outside edge of the wall top plate, to close off the opening to the attic. A fascia board on the end of the rafter tails held up the gutters. With this construction method, outside you could look up and see the rafters and the underside of the roof sheathing in the overhang area. Those parts were painted. That was a common method of construction many years ago. Most were updated to add the 2x4s that go back to the house wall, soffits added. And if done right, the close-off blocks between rafters were pried out first, and louvered screened vents were put into the new soffit at regular intervals. In other words, making it like houses of today.

If you have something different, it would be interesting to see!
 
Last edited:
OP - include a picture of your roof overhang or soffits so it's clear what you have.

I had an old house re-roofed, and I could see the soffits were badly vented. They had tiny screened holes every now and then. I got this corrected by cutting open the thin plywood making the holes as large as possible (could stick head in each one at least) and putting vented aluminum over it. Then put lots of roof vents on top (mushrooms). Next time the roof was done, no rot, and put in tower roof vents.

While a ridge vent is fine, the issue is where is it going to get the air to let out ?
 
Have you interviewed roofers and got their suggestions on attic venting?

They're usually well versed in this subject.
 
Bamaman said:
Have you interviewed roofers and got their suggestions on attic venting?

They're usually well versed in this subject.
Click to expand...

Some are, on the other hand I had to stop my roofers on another house from putting mushroom vents in the garage roof. He had already cut the roof, so I got one there, and the rest for the attics.

My garage is Very Vented without any roof vents.

OP could talk to a few roofers, as obviously the ones that did the ridge vent, only did a partial job. Was it lack of understanding/knowledge or simply didn't care to do it right ? Or did OP influence their actions ?
 
I recently purchased a home in coastal South Carolina and we have little need for ice dam protection. The previous owner had the attic foam insulated...spray foam on the "ceiling" of the attic and all fiberglass insulation removed between the attic and the house. This makes the attic part of the house interior. Also, all attic venting was removed/sealed. They stored art work in the attic because the area was dry and comfortable even during the hot summers. That is a common energy reduction solution in this part of the country, and our energy bills are less than $130/month for a 3000 sq ft home. This would be a significant change to your current arrangement, but might be something to look into.
 
I haven't heard of this being done, but it just came to mind. What about adding a roof vent with a tube running down to within a few inches of the attic floor. Similar to how fresh air used to be brought into the furnace and water heater area. use a bathroom roof vent which would be protected from the rain and snow. Perhaps a few of those with a plenum inside running the length of the house along both eves could bring in fresh air to the bottom of the attic space along the outside wall. It might work, no?
 
Interesting, my BIL just had foam installed on the upper side of his roof. This is my DW's childhood home they just bought and renovated. He claims his atttic stays about 10-15º warmer than the inside of the house. I might do the same after I see how it works through our hot humid summers.
 
CRLLS said:
I haven't heard of this being done, but it just came to mind. What about adding a roof vent with a tube running down to within a few inches of the attic floor. Similar to how fresh air used to be brought into the furnace and water heater area. use a bathroom roof vent which would be protected from the rain and snow. Perhaps a few of those with a plenum inside running the length of the house along both eves could bring in fresh air to the bottom of the attic space along the outside wall. It might work, no?
Click to expand...

Interesting idea, but I think if I leave the gable fan it would just suck air backwards like from the ridge vent and if I have no fan, it would just be a top opening with insufficient air intake.
 
Regarding the other questions.

I live in southern New England and did have quite a bad ice dam problem before the roof was replaced in 1989. That was when the ice-water shield was placed under the shingles. Shortly after that I replaced the insulation in the attic floor joists with pink stuff and put a second layer of pink on top. Maybe 20 inches total. I think that cooled the roof and do not remember any serious ice dam problems but winters have not been as bad lately.

The roofing contractor was the one that suggested putting the ridge vent in. I don't think they were any genius on attic ventilation.

I can't easily get pictures, but from what I remember when I did the insulation was that the rafters sit on top of the wall opening and were cut at an angle to fit. I am pretty sure that they do not extend past the wall.

There is a facia board and I remember the roofers saying some had to be replaced.

I can't see the rain gutters now because I had them replaced and they have a cover to keep the leaves out. But as I remember the old ones, they were attached (to the facia board?) by long spikes that went through both edges of the gutter and into the board. So they sit just outside the lowest shingle (maybe a half inch of shingle overlaps) and are either even or slightly lower than the shingles.

I have not yet obtained any professional advice. Last week I was simply planning to replace six or eight pieces of shingle that broke off. These were about a one-third width and half length size piece that snapped off exposing the normally covered part of the shingle below it. I did not want to get involved with trying to remove the entire broken shingle, so I cut a piece of new shingle with an inch or so extra to get under the one above it, slopped a lot of vinyl caulk to hold it down and put five roof nails to hold it that were nailed through a puddle of caulk so they won't drip. I hoped this would hold for one year until I do the roof. But looking with binoculars, it seems that the shingles are not flat in more area than I thought which led to trying to contact a roofer this week.

I asked around for recommendations and only got one. I called them but they have not returned the call for three days. They did respond to my text asking for a call.

I sort of know the town guy who does the building permits. I think I should ask him if he has any suggestions.
 
Telly said:
If you have an ice and water shield, you probably are in an area that you can get ice dams. I would think the last thing you would want to do is to cut any openings into the shield area!

I'm missing your "no soffits" configuration. A pic would help. In the midwest, I would occasionally see two types of "no soffit" pitched roofs.

One was a cheap (I think they looked awful!) construction where the rafters literally end at the outside wall's top plate. There was no roof overhang at all. Gutters were attached to the fascia board which closed off the ends of the rafters. These houses were more prone to leaks, and I think they looked like crap with their sawed-off appearance.

If you have something different, it would be interesting to see!
Click to expand...

I think I am your first type, which I left in the quote.
 
CRLLS said:
I just searched for roof vents with no eaves. I like what I saw. It looks like it would work better than the O'Hagen vents. YMMV.

Owens Corning VentSure Inflow Eave Vent
https://www.owenscorning.com/en-us/roofing/products/inflow-vent
Click to expand...

I would think of that as a very small soffit, OP if using that idea should remove the facia board (where the gutters hang on) and cut open the wood blocking that is probably between the rafters. Could staple 1/4" opening to 1/2" opening wire between them to stop squirrels but allow lots of air flow.
 
joesxm3 said:
What is a solar blaster? And how did you handle getting enough intake for the blaster to pull the air through. Did you recut the soffit vent holes?
Click to expand...

They are roof vent fans that run on solar energy. Normal roof venting uses normal air movememt from sofit to top vent to remove hot air from attics. These help when venting is not enough

https://www.solarblasterfans.com

Even though the vent holes are missing, there is still some air able to get in. Just not enough to use just a roof cap vent. The solar blasters create artificial air movement pulling air to the vent and out.

I chose not to fix the sofit because the height of the house, and I would have needed to replace the sofit after removing it and cutting vent holes. Not work I was prepared to do myself.. I got a couple of estimates and it was more cost effective to use solar blasters.
 
We just had our roof replaced last week and also replaced 4 dead vent fans. We are in Texas, so we need all the attic venting we can get. The problem with the vent fans is that the motors burn out just about the time the warranty runs out. We explored the solar powered vent fans, but they’re at least 2x the price of the electric ones with a worse warranty. I can’t imagine a fan motor pulls all that much electricity.
 
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