One nice thing about living in Southern California is that the weather is perfect for whole-house fans. To perform the calculation you requested, we'll have to make some assumptions. Martin, How about the un-powered vents? Talk about wasting energy! Just as a note : We usually only run the AC when it is so hot that we just have to (which is not often). It is a low slope ashpalt shingle roof with deteriorated batt attic insulation. I have a gas furnace & a gas hot water heater in the basement. It is not a matter of comfort, but rather, a matter of survival. Tighten the screws with a screwdriver. Thanks for catching my error. Increase your ventilation area, or consider a different solution. 2) My mother-in-law stays in her hot home all day and was considering replacing her central A/C system with one of higher capacity. The best way to lower asphalt shingle temperatures is to choose white-colored shingles over black shingles. If you see mold in an attic (and you know that you don't have a roof leak), it's almost always a sign of a leaky ceiling. However, this option still leaves me with a heat loss nightmare in winter. For the benefit achieved, creating an unvented and conditioned attic is way too costly and complex. Evan, My understanding is that it is possible that my attic is too hot (I have adequate insulation since I added some prior to new roof and new gutter install. Another thing to remember is to cover the large attic exhaust vent in the off season. If you push hot air out of your attic, more hot air from inside your home will just rush in and . If I go with the SIP roof, there will no longer be a vented attic space at all. I think the furnace is original to the house, which was built in 2006. Fan has on/off switch in our office, not a thermostat. The AC handler is in the attic. First things first. Response to Derek Roff Asphalt is a great material for absorbing solar radiation and has poor thermal emittance. In the summers the vents spun day and night relentlessly. By morning, the outdoor temperature might be in the fifties or low sixties, and the indoor temperature might be 68.. The total area is 37.7 square feet. If you are worried that your ceiling is still warm, the solution is simple: pile on a little more insulation. Response to Gary Seifer The second story is over back half the house and the original front half of the attic butts up against our clothes closets and the master bedroom. Tamarack is a fine company with leading edge insulation technology but you do your readers a disservice by inserting your opinion that they "make the best whole-house fans available". Roof Vents Remove Warm Air during the Winter Too many people believe that because heat rises, ventilating an attic space during the winter means you're releasing warm air and creating a drag on your heating efficiency. My advice is to skip these fans entirely. Will never know. So, the trade-off varies depending on your climate of course. For more information on the solution, see this article: "How to Install Rigid Foam On Top of Roof Sheathing.". Just use the whole-house fan when nighttime temperatures are cool and daytime temperatures are hot -- that's all you need. I never had a problem with icicles before the new roof and gutters. So it gets HOT up there, even here not far from the ocean in L.A. In that article, I wrote: "The NightBreeze includes a variable-speed air handler with an ECM blower, a hydronic heating coil, a large motorized damper to control the intake of exterior air, and a wall-mounted control unit. Does everyone you know live in a dilapidated log cabin? The AC will not shut off. [Photo by Energy Vanguard] Here in the South, we love our humidity. If you want to install a whole-house fan, go right ahead. Q. That's good. Your research into attic fans is of great interest. Your article does a great job of outlining how this happens. If your house has an unvented conditioned attic, then your attic is just another room in the house -- just like a bedroom in a finished attic. I have a metal roof, I am getting icicles on my gutters. So, I put in an attic fan to relieve the hot ceiling. attic fan but with no attic Do not use a rotating fan. Combining an attic power vent fan with a ridge vent is usually not recommended because: It could reverse the natural flow of hot air out the ridge vent. A right-size mini-split will cost a LOT less than a conditioned attic, and a good one will operate at twice the as-used efficiency of a typical oversized central air conditioner, even if the ducts were inside the insulation & pressure boundary of the house. 3. Whether the investment in the equipment can be justified is another question. ". I've looked at other houses in the area. Tamarack fans have been around for years, and have a good reputation. A. There are soffit vents but no ridge vents. An attic fan is what it sounds likeit's a fan installed on the ceiling of your attic. After all, the cellulose insulation doesn't require any electricity. The purpose of a whole-house fan is to rid your home of heat that builds up while the sun is out. So I guess there would have to be a duct from the fan discharge through the roof. Like so many other "plug in" You live in a mild climate, and the occupants of your house have managed to survive for 70 or 80 years without insulation. (Remember all make up air going to the air space is coming from the outdoors. Scott, Response to Lesley Matson A better option would be the TC1000-H fan from Tamarack -- a model with an automatic insulated damper that prevents heat flow and air flow when the unit is not in use. Cathy, 1 by builders and are the highest attribute made in the USA! Response to Kris Knutson Cooler asphalt shingles last longer than warmer asphalt shingles. Is it just inefficient, or is there some sort of danger to that kind of setup? So instead creating a negative pressure with attic ventilators I am creating positive pressure. In the meantime, we got another air conditioning person to come out on Friday. That's a good point. If your attic doesn't have any problems, I wouldn't worry about adding more attic ventilation. So, if you can lower the attic temperature by 15 F for under $375 (with no recurring energy penalty per a powered attic ventilation fan), that would be the more advisable route. Read the other comments on this page, or do some Googling -- you can buy a whole-house fan that is designed to be mounted in a sloped roof assembly. Jrowen42, Without spending a fortune I was just going to replace the ventilation fan in the attic. Perhaps a 10 year payback in the example given, which is quite good in the green building business. You have described two buildings with "hot ceilings." Regardless of what the insulation level is, there will be some level of energy transfer from the warmer attic to the cooler house. However, if you expect that you will need to continue running your air conditioners, insulation makes more sense than a radiant barrier. Whats wrong with a large CFM attic power vent fan (say 1400-1600 CFM) and a set of ceiling shutters ? But even if the fan doesn't blow out the pilot, I hadn't considered the fact that it would force air back through the vents. Thank you, Martin, for showing me how to do the heat-loss calculation, and providing an example. Your primary point is that an attic fan results in an energy penalty when it draws conditioned air through a poorly sealed envelope. Well, it's possible that it will lower the attic temperature a few degrees. The previous owners installed a gable fan at one end of the crawlspace. I have a 3 level spit house. Click here to see a website with many inexpensive models of whole-house exhaust fans for flat roofs. Walk barefoot on an asphalt road and see how that works. A. As long as shingle manufacturers ignore the effects of shingle color as a determinant of temperature, they may be admonished for asserting so strongly the importance of venting to control temperature. I would be very happy to assist you in a thorough market overview which I do regularly for the http://www.WholeHouseFanGuy.com. I have corrected my earlier comment. Whats a good solution for a 1960s brick ranch house that has the furnace and ductwork installed in the attic? Another possible explanation is that you are really battling heat sources inside your garage, including your water heater, your freezer, and your clothes dryer -- and that your powered attic ventilator is a placebo rather than an appliance that succeeds in altering the temperature of your garage. Dana: I'm actually not sure if it has a standing pilot or electronic ignition, but I'm pretty sure it's getting combustion air from the attic. Consider a different roof heat-gain management system, if you can afford a long-tem investment. We have a 2-story 2600 sq ft home, and installed the EXCELLENT Tamarack Ghost along with two attic fans, thermostat controlled, one blowing air out of the the attic, and one blowing air in (against the advice of my electrician, who wanted both blowing air out). Cold climates will have a higher T than I assumed, and warm climates will have a lower T than I assumed. Again, keeping other things equal to your example, this would give us a seasonal cost difference of roughly $6. Lesley, Other Solutions Response to Chris Grabowy I should have made that clear. This method allows the installer to place the system performance gauge right in the garage. I bought a ranch house last year in Central PA. Response to Hannah Mills-Fee Attic has a light colored roof and is well ventilated with extensive eave venting, eyebrow vents, gable end vents and two turbine vents. I will use a radiant barrier decking, but does a powered attic ventilator make sense here ?? The cost of a conditioned attic is high- it may not be worth it. Is it a crawl space? ), weather variables, and behavioral changes. Martin: Thanks. How often should I run it? The cool roof + code compliant attic-R has reduced the radiated heat from the ceiling to manageable levels, and humidity is the primary comfort issue. Over 24 hours, that would be 5,856 Btu. Living the the San Fernando Valley in the summer we would often run the AC for a few hours during the later part of the afternoon and then switch to the whole house fan once the temp outside fell below the AC set point. The ventilators are programmed to come on when the attic reaches 100 degrees & go off when it reaches 90. You are basing your hopes on the "smart arrow" theory -- namely, that the air entering your attic will follow the "smart arrows" shown in diagrams produced by soffit vent manufacturers. thanks Bottom line, for my unique circumstances the PAV works, a bridge to the next step. I'm not sure where you are thinking of installing these "motorized registers." I don't use it often , so that she will not be cold.
Geotechnical Engineering Companies In Germany,
Articles D