Another attic ventilation question

[Jack]

I have a hip-roof colonial. The attic is about 1100 sq ft. There is a ridge vent across the top of the roof, plus soffit venting all the way around. In the attic, there is a heating/cooling system. During the summer, it gets unbelievably hot, which really affects the cooling ability of the system. . I have googled this issue, and it seems that power roof vents are not the way to go to lower the temperature. If I can't use a power vent, what are the options ? . Thank you for your time.

[ValveJob]

You did a poor job of googling. Lots of people including myself have lowered the electric bill and the temp of my attic using a power vent in addition to my ridge vents in my hip roof.

How many linear feet of ridge vent do you have?

Well thats not enough. You can supplement the ventilation with power vents.

[Proctologically Violated©®]

That's a big attic--is that the floor area, or the roof area (both faces)?

I have an attic of about that floor area, w/ a crappy mushroom fan. I insulated between the joists w/ fiberglass, covered by 1/8" paneling, which made all the difference in the world. And, essentially no other venting. The teeny ones that were there were covered, and instead I crack the attic door/ladder to vent the warm air rising to the top floor from the house. The fan is on a thermostat.

A small A/C, about 6,000 btu, makes the space entirely inhabitable in the summer, ditto a small dehumidifier in the winter. In the winter, I put a piece of paneling over the fan opening.

I personally don't understand the hyper-venting of attics. At least not in the context of good insulation.

Insulation roolz.

[mm]

groups.google or www.google ?

I'm not going to get into thisat this time, but I will say that fan or not, you should check your soffit vents outside every 10 or 15 years to see if they are clogged with airborne plant life.

The first time, mine had a layer about half as thick as the lint filter on the dryer when it starts to whistle. I think sometimes there is a lot of milkweed around here, but I"m sure there are other things that do this too. .

[Jack]

[Phisherman]

I, too, have a very similar situation. There is a heating/cooling system up there and I have ridge vents. I added additional insulation around the ductwork and added a wooden floor last year. That doesn't reduce the summer heat, though. My plans are to add a side louvered window with a fan for those incredibly hot 100-degree days.

[CJT]

I'm a big fan of radiant barriers. Google is your friend.

[CJT]

Don't confuse "whole house attic fans" (which draw interior air into the attic) with "attic ventilation fans" (which draw from e.g. gable to gable or soffit to roof). You shouldn't be pulling any appreciable amount of interior air into the attic with the latter -- if you do, you have inadequate sealing.

[CJT]

I have a thermostatically controlled gable fan, and it runs a lot during this time of year. I'm convinced it relieves a lot of the load from the central A/C. But don't expect one to save you a lot on electric bills; they use quite a bit of energy on their own -- maybe even as much as they save (assuming you've got decent attic-floor insulation).

[ds549]

what ellse are you going to do besides power roof vents? i have added power vents to ridge vent setup with success. useing one or two actually sized a little bigger for the square footage works very well. just speaking from actual have dones. lucas

[Proctologically Violated©®]

If the *sizing* of an attic fan is an issue for you, you might try finding a variable speed one, or putting in a variable speed motor. I haven't seen one of these myself, but it's a good idea.

I sort of did this myself, as my cheapo mushroom attic fan froze up, and I then kluged in a Panasonic 3-speed oscillating fan, which also froze up. Worked great, for a while. Then I scavenged a pretty heavy-duty 3-speed motor/fan from an A/C unit. Only problem is, there's not much of a difference among the 3 speeds.

But iffin there WERE more of a difference, it'd be great. :) It does do the job tho, and is thermostatically controlled--with the A/C thermostat. :) :)