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Anyone have one? I was going to make my own, but couldn't find a decent solar panel and fan combo that I liked. Preference is for a gable mount so as to not cut any holes in the roof.
How well does it work?
Does it move a decent amount of air? How big is the fan - CFM?
Have you noticed that you need fewer fans on because it keeps the house cooler?
How much and where to buy locally - or where not to buy?
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If you are writing about venting roof attic areas then powered fans usually are not needed. Heat rises and those spinning ridge "chimney" type vents (sometimes called barn vents)are spinning by the action of warm air rising.
I have a well insulated roof and no ceiling fans. Very comfortable all the time.
Assume the best and ask questions.
Punaweb moderator
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I don't own it. It is a rental. I am trying to find a reasonable solution to the heat problem.
Lack of insulation is part of the problem...as is the very small amount of pitch of the roof.
There isn't much air space up there. I have a point able, infrared thermometer and the temp at the ceiling in the living room will hit 90 degrees on a warm day.
According to some people, I guess it is a good thing that when the house was built, the codes determined that there was no need for it? A few hundred $ extra when the house was built would have paid for itself numerous times over the years in keeping the house cooler without the need for fans. (built in 1991)
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Some of these houses in Hawaii remind me of "The Box" in the film The Bridge on the River Kwai.
Nevertheless, are you intending to modify a property you rent? or provide some advice to the owner?.
Another possibility is applying a coating on the roof. The cheapest and most available is Snow Roofing. A thick white paint on coating. White reflects heat. It's often more effective to deflect the heat than try to move it around. There are other liquid ceramic coatings which are better than Snow but cost more and have to be ordered. By better I mean that they do a better job and last longer. Snow is available at HPM.
Applying a white coating will bring immediate relief.... maybe not as much as you want if the roof is very low and close to your head but it will reduce temps.
You could offer to do the painting if the property owner provides the paint and brush. I believe Snow is rated for potable grade coating.
Assume the best and ask questions.
Punaweb moderator
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quote:
Originally posted by Rob Tucker
Nevertheless, are you intending to modify a property you rent? or provide some advice to the owner?.
A little of both. They didn't build it, but are planning that long-term, they will move here. I hope it's real long-term as I really like the spot it is in. In the meantime, I would like to make some improvements that will benefit both of us. Getting the attic cooled down will have a number of benefits, including saving the ceiling drywall from the heat and humidity in the attic area.
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We have a solar powered gable vent for our ohana roof. It really did increase the ventilation in the ohana attic area & was not horrendous to install -2 days total, with a wee bit of head scratching time. The kit was from Lowes, but I think that I have recently seen them at Home Depot... There was a thread on this last year:
http://www.punaweb.org/Forum/topic.asp?TOPIC_ID=7273
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Carey - thanks for that link. Looks like a lot of people have houses with no insulation and heat problems... imagine that?
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Keeping the heat out is your best plan. Painting the roof white will help tremendously. Installing a radiant barrier in the attic will reflect about 95% of the radiant heat. You will be amazed at the instant temperature reduction. The cheapest one on island is at Home Depot. It is a thin film of aluminum sold in 4' rolls. It is about $60 for 500 square feet I think. If there is room in the attic, you can get up there and staple it up in a couple hours. You must leave a gap between the roofing and radiant barrier of at least 3/4" to make it effective. Stapling to the underside of the rafters is usually the easiest way to go. This would be a lot easier and cheaper than painting the roof and more effective.
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Gable end vents should work well as long as there are sufficient rafter vents. Those holes they drill in the frieze blocks are too small. You have to let the cooler air in as well as letting the hot air out. Electric or solar fans will help. Try Grainger (on line) or Home depot.
Dan
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I am surprised that skylights than can open/close i.e. ventilate and provide light are not used more often.
