ridge vents - are they worth installing?

[phil]

planning to do the second side of my roof this summer.
for those not familiar with ridge vents..
the ridge vents want to have an inch or two gap in the plywood near the peak. then they lay a plastic mesh about 18 inches wide over the peak. near the bottom of the first shingle from the top, the plastic mesh forms about a 1/4" screened gap to let air under the mesh so then the roof can vent through there.

Ive got a couple of 8 inch square vents. I added one more for my bathroom fan. It gets hot in my attic in summer. I've never added a ridge vent before and I have some questions on the installation. there are a variety of makers. there is some cost. does anyone else here have ridge vents and if so what were your opinions? has anyone else installed one before?

my attic is divided into living space and storage where the roof is less than 4' tall. I have that division wall insulated. there is some insulation above the drywall but there is some strapping between the drywall and the studs so the insulation should be sort of loose up there. inside the storage area I have not insulated against the roofing as this causes the roof to run hot and not last. I have some venting into the storage space that is 6 feet wide ( about 10 feet of my lower roof deck) and runs the length of my house on both sides. venting into this space could be increased. i have easy access to the space. Its not quite how I'd build it from scratch but it would probably allow it to expel some heat up there.

one little Issue I have that isnt' a perfect situation...
When I drywalled there I was pretty gren and had just bought the house. I hired drywallers to fly at it. we removed all the droopy beaverboard.
We put 3.5 inches of pink up there against the plywood. knowing what I do now I would have put a corrugated sheet there so the insulation wasn't against the roof to allow venting up to a ridge vent. under the 2x4 rafters it had some strapping. I made an agreement with the drywallers to remove all the strapping to gain ceiling height but being a couple of jerks they boarded it up when I went to work without removing the strapping as we had agreed. . As it is I probably have some gap due to the strapping but its underneath the insulation and above the drywall. tearing that all apart isn't practical at this point because its all finished. I still think adding a ridge vent would help a bit as the air probably would flow there somewhat but I know it isn't quite right.

to add one I might need to strip the top row of roofing I've completed but that's not a big issue. I couldn't complete the ridge cap last year because I hadn't finished both sides yet so for the winter I sort of just nailed a few shingles on the peak , most of them blew down but It didn't leak. the top row droops over a little and it has a membrane so I guess that was enough to get through winter.

I have until I get to the top of the second side to make a decision on wheather it would be beneficial to add ridge venting. i figure its probably an extra 200 or so for the plastic stuff, and i maybe have to tear off a row of shingles, maybe 50 bucks for that. How well the ridge vent would work is hard to determine or measure.

thanks,
Phil

[Manalto]

Having spent a number of years in Bellingham, WA, I would categorize the PNW climate as on the cool side of moderate. I think of ridge vents as an escape valve for attic heat in places with hot summers. However, your weather may be different enough to warrant them. Do you have gable vents? You could always install them as a fail-safe and I'm sure they'd pay for themselves in air-conditioning cost savings in 200-300 years.

[phil]

I put one gable vent in , my blower sucks in air and exhausts it through some ducting so that helps a bit on the sunny side, not enough though.
right now it's 28 degrees, that transfers to 82.4 summers have been like that from this time of year to September since global warming took effect . we have a huge fire problem now and that isnt' helping slow the cause and effects. Califonia has seen some wild fires too.
My guess is it will continue in that direction because we have no way to correct from the sequence of events we have seen so we can't change what's to come. I dont think a speedy correction in pollution output would stop the issue from following the sequence for weather changes. so many of the issues are linked. the fires drop ash on snow it darkens the snow then it accepts more light. the snow melts and has less reflectivity than the ocean and that accelerates the problem more. the dryness is causing the fires to get bigger and burn faster. not all agree some deny it entirely and I wish I could think otherwise.

When I was a kid we used to typically get humid rainy periods during the summer but it changed quite dramatically. from September to march we do get lots of rain.
we don't see the humidity anywhere close to the east due to the weather patterns. That's always been the case so at least it's a dry heat which is easier to take. we are probably very similar to Seattle. Anyway .....I can't change the weather!

Another solution might be to add more gable vents and a fan that is temperature controlled so it would come on over 100 or so. I bet it's easily 120 in the attic space. It gets stinking hot until I open the windows up there, especially in the storage space.

in winter maybe the ridge vents loose heat and you cant' really go shut them. i would imagine it also causes some heat loss.

[Manalto]

in winter maybe the ridge vents lose heat and you can't really go shut them.

Good point. In winter you'd make that trapped-air layer of insulation in the attic less effective with ridge vents if there's no way to close them.

[Gothichome]

in winter maybe the ridge vents lose heat and you can't really go shut them.

Good point. In winter you'd make that trapped-air layer of insulation in the attic less effective with ridge vents if there's no way to close them.

We’ll hold on there. Unheated attic space should never have restrictions in air circulation. In a perfect set up you’ll want your attic to be the same temperature as the outside ambient with air flow in and out of the attic. This is critical in colder climates. In the winter heat and moisture does escape into the attic from within the heated envelope. With the dew point drop caused by the cold attic the moisture falls out of the air. With out attic circulation it settles into any thing that will absorb it such as rafters, roof decking causing rot. The air circulation absorbs this moisture and caries it away.
In the summer, the air circulation is critical in keeping the roof temp down. With the sun shining down on the shingles you need that circulation to cool the roof deck down so your shingles survive.

[Manalto]

Nobody said to seal it tight. A professional may be able to advise how much circulation is advisable depending on the season.

[phil]

I guess humidity could be monitored. Ive got 4 access doors to the space so its easy to open them up for a look. other than a few dribbles near the chimney I've never seen much sign of humidity. You'd think because it rains so much here in winter it would be an issue but I guess its vented enough that I'm not seeing rot or high humidity. it always seems super dry in there.

I need to make a screen for the bedroom window. we can open one and its ok because its a long way down but I left my ladder up knowing that I have to finish up my roof. my cat sneaks out on the roof, climbs down the ladder and goes out to party. and I try t o keep her in at night. yesterday I heard her jump out on the roof and went outside to the bottom of the ladder and foiled her escape plan
She goes down the aluminum ladder nose first one rung at a time. funny to watch