Home |
Search |
Today's Posts |
|
Home Repair (alt.home.repair) For all homeowners and DIYers with many experienced tradesmen. Solve your toughest home fix-it problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss |
#2
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
"Andrew Barss" wrote in message ... I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd put more insulation in then the vents. I wouldn't mess with the roof. Too expensive for your return. Consider a ridge vent. They are not that expensive and supposed to be the most effective. |
#3
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 1:06*pm, Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. *The house has a peaked roof, with a low attic that has minimal access. *The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). *We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. *The curent roof is light-colored shingles, and in quite good condition. * * * * Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss Pay for an energy audit and get a blower door test done. There are many ways to increase efficency that will be outlined by an audit, you may find windows or another issue more important. |
#4
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 1:06*pm, Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. *The house has a peaked roof, with a low attic that has minimal access. *The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). *We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roofh treatment. *The curent roof is light-colored shingles, and in quite good condition. * * * * Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss You definetly need a powered roof mounted Attic Fan which comes with its own thermostat that you typically set at 95 f. (on) . I wouldnt be without one in the South. Ive had them on ALL of my houses with tremendous improvement..plus it makes your roof deck last longer. The Attic Fan would pull in cooler outside air thru your two end grilles and exhaust the superheated attic air very very well. You can get them at any Lowes, Home DePot, or Menards store. About $80 . Forget about static Ridge Vents...they are virtually useless -- you need to FORCE the air out of the attic . Further, I would lay batt insulation in your attic on top of the blown in insulation after you smooth it out so its level. Use R30 batt insulation which will come 24' long and 15" wide (also available 24" wide) and is 9.5" thick. I just did mine and immediately noticed the difference. These two improvement done together will make your inside much more comfortable as well as reduce the runtime of your cooling system (as much as 30%) thereby saving you money . Ive vacationed in Tucson 7 times over the years and almost moved there in 1980 . I spent my honeymoon on Mt. Lemmon at SummerHaven . |
#5
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 12:06*pm, Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. *The house has a peaked roof, with a low attic that has minimal access. *The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). *We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. *The curent roof is light-colored shingles, and in quite good condition. * * * * Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I have seen about a one-third reduction in electricity bills by blowing in insulation in the attic. Make sure you cover electrical fixtures before blowing in the insulation. If you don't have thermostatically controlled blowers in the attic, get some. Solar screens also help a lot. Andy |
#6
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? "d", although not the whole story, is probably the closest for old construction. Some other things to take into consideration for hot climates: Vented roofs reduce the total solar heat gain by roughly 3 to 5%. Consider installing ridge vents instead of the passive rotary vents along with your vented soffits. Clay or concrete tile shingles can reduce the solar heat gain by 10 to 15% in a vented roof. Color is not a big an overall factor as you might think; material is, however. Dark colored clay or concrete tile shingles outperform light colored asphalt shingles, but in general light colored roofs do perform better than dark, although it may not be significant taking material into account. Radiant barriers can have a significant effect on reducing solar heat gain on asphalt shingled roofs, not so much on clay or concrete shingles. Best is a product like "tech-shield" used as decking, better than none at all is the spray on radiant barrier paint. Keep in mind that you need at least 1" of void space below the radiant barrier for maximum effect. Radiant barriers do perform significantly better on vented roof systems. Basically, unvented roofs with clay or concrete tile shingles and R-19 insulation or greater; and vented roof systems, with mechanical equipment and ductwork within the conditioned space, and R-19 or greater ceiling insulation, perform the best in the Southwest. If you do decide on "e", your best bet for hot climates is a design that incorporates AC ductwork and air handlers within the building thermal barrier, and a vented roof with clay tile or concrete tile shingles and an R-30 or greater ceiling insulation. If the AC ductwork and air handlers must be located in the attic spaces, then go with a design that incorporates an unvented roof, creating a conditioned attic space for the mechanical equipment. Do your homework and find some "green" building seminars in your area .... the woods are full of them. -- www.e-woodshop.net Last update: 10/22/08 KarlC@ (the obvious) |
#7
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? In addition to the other wonderful suggestions, I'd offer the following: 1. Light-colored roof. A good idea, BUT... drive around your city. Do you see any? No? Why not? The reason is that they discolor in a ghastly fashion from the junk in the air. In places like Rome, they have permanent pressure-washer crews prowling the city cleaning off the marble statues. IF you're lucky, one side of the roof may be completely unseen by the picky-public and you could get away with a white roof there. 2. You can't have too many soffit vents. If your ENTIRE soffit is a vent, that's good. I'm not sure what birdboard might be, but if it's anything like the perforated Hardiplank, it's probably insufficient. While the holy plank stuff has a lot of holes, their total combined area is miniscule. Experts agree that the unobstructed soffit vent area should be 1 sq in for each 1 sq ft of attic space (again, more is better). |
#8
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Master Tang wrote:
"Andrew Barss" wrote in message ... I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd put more insulation in then the vents. I wouldn't mess with the roof. Too expensive for your return. Consider a ridge vent. They are not that expensive and supposed to be the most effective. If you don't have the soffit vent the ridge vent doesn't help all that much--air has to come in before it can go out. The channel from the soffit to above the insulation is easy--you get it in premolded plastic from Home Depot for not much money. |
#9
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
"Andrew Barss" wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. snip As the old saying goes, "Advice is usually worth what you pay for it." As someone else suggested, contract with a reputable firm and have a total energy audit performed. It will cost a few $, but it will save many times that cost. Otherwise you are flying blind. Lew |
#10
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
"J. Clarke" wrote in message ... Master Tang wrote: "Andrew Barss" wrote in message ... I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd put more insulation in then the vents. I wouldn't mess with the roof. Too expensive for your return. Consider a ridge vent. They are not that expensive and supposed to be the most effective. If you don't have the soffit vent the ridge vent doesn't help all that much--air has to come in before it can go out. The channel from the soffit to above the insulation is easy--you get it in premolded plastic from Home Depot for not much money. I'd assume (?) the installer of the ridge vent would know that. The one that installed mine did. |
#11
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Wed, 17 Jun 2009 18:06:57 +0000 (UTC), Andrew Barss
wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. .... I would suggest blowing in more insulation for now. In the future your shingles will fail and then you can remove them, add a ridge vent and open up the soffits as much as possible. At that time I would consider adding a layer of insulation (high efficiency foam) on the current roof, after removing the shingles, and then the new roof over that. The cost of energy is just going to continue to climb. |
#12
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd go one better than just adding active fans at either end of the attic. I'd also add a whole house fan, mounted in the floor of the attic (ceiling of the living area) to pull cooler air up from the house into the attic. This air will be cooler than the outside air and will create a cool airflow throughout the house. Here's a fact sheet from consumer reports: http://blogs.consumerreports.org/fil...use-fans-1.pdf ~Mark. |
#13
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
"Woody" wrote in message ... Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd go one better than just adding active fans at either end of the attic. I'd also add a whole house fan, mounted in the floor of the attic (ceiling of the living area) to pull cooler air up from the house into the attic. This air will be cooler than the outside air and will create a cool airflow throughout the house. Here's a fact sheet from consumer reports: http://blogs.consumerreports.org/fil...use-fans-1.pdf ~Mark. So he should suck in the 113 degree heat and pump it into his house? |
#14
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
A couple years ago, it was summer time. The company I was
working for, we had been installing an air handler and AC in the attic of a house. We had a roof company install a power vent. After they installed, I temporary wired it in, and turned it on. You could feel the difference almost immediately, with the fan dumping the hot, humid attic air out. I'm a believer in roof power vents based on that. -- Christopher A. Young Learn more about Jesus www.lds.org .. " wrote in message ... You definetly need a powered roof mounted Attic Fan which comes with its own thermostat that you typically set at 95 f. (on) . I wouldnt be without one in the South. Ive had them on ALL of my houses with tremendous improvement..plus it makes your roof deck last longer. The Attic Fan would pull in cooler outside air thru your two end grilles and exhaust the superheated attic air very very well. |
#15
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Andrew Barss wrote:
I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss For energy efficiency I would recommend more insulation above the ceiling rafters. Roof venting will lower the temperature in the attic crawl space but the main advantage of proper roof venting is that it extends the life of the roof. If you do vent the roof at the ridge you should also add soffit venting at least equal in area to that of the ridge vent for proper air flow. See: http://www.roofhelp.com/ventilation_main.htm http://www.cor-a-vent.com/pdf/balancedventilation.pdf and http://www.energysavers.gov/your_hom.../mytopic=11390 -- Jack Novak Buffalo, NY - USA |
#16
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 4:16*pm, "Stormin Mormon"
wrote: A couple years ago, it was summer time. The company I was working for, we had been installing an air handler and AC in the attic of a house. We had a roof company install a power vent. After they installed, I temporary wired it in, and turned it on. You could feel the difference almost immediately, with the fan dumping the hot, humid attic air out. I'm a believer in roof power vents based on that. -- Christopher A. Young Learn more about Jesus *www.lds.org . " wrote in message ... You definetly need a powered roof mounted Attic Fan which comes with its own thermostat that you typically set at 95 f. (on) . *I whouldnt be without one in the South. Ive had them on ALL of my houses with tremendous improvement..plus it makes your roof deck last longer. The Attic Fan would pull in cooler outside air thru your two end grilles and exhaust the superheated attic air very very well. Absolutely. Nothing else will help as much as a Powered Roof Mounted Attic Fan with adequate makeup air via perforated soffits / gable vents. |
#17
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 2:35*pm, Woody wrote:
Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. *The house has a peaked roof, with a low attic that has minimal access. *The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). *We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. *The curent roof is light-colored shingles, and in quite good condition. * *Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd go one better than just adding active fans at either end of the attic. I'd also add a whole house fan, mounted in the floor of the attic (ceiling of the living area) to pull cooler air up from the house into the attic. This air will be cooler than the outside air and will create a cool airflow throughout the house. Here's a fact sheet from consumer reports:http://blogs.consumerreports.org/fil...use-fans-1.pdf ~Mark. My parents had one of those in the 1950's before they had AC. In hot, humid weather the who house fan basically blows the hot air around. I think the goal is to blow the hot air out of the attic so it doesn't migrate into the house. Andy |
#18
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
ransley wrote:
On Jun 17, 1:06 pm, Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss Pay for an energy audit and get a blower door test done. There are many ways to increase efficency that will be outlined by an audit, you may find windows or another issue more important. Maybe Tucson is big enough so he can find somebody who will do that. I tried around here- none of the Utility, Insulation, or HVAC companies offer the service. I'd have to pay hundreds of dollars to have somebody come over from the Big City to do it. -- aem sends... |
#19
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Wed, 17 Jun 2009 18:06:57 +0000 (UTC), Andrew Barss
wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. How thick is the insulation now? Blown insulation will settle over time and perhaps not have the same R value. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. In a pinch, staple cardboard from the vent and above the blown in material, Spend a little time and find out why your doors and windows, leak most energy. Smoke pencil, exotic incense helps show a draft. DIY home audit |
#20
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Nova wrote:
Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss For energy efficiency I would recommend more insulation above the ceiling rafters. Roof venting will lower the temperature in the attic crawl space but the main advantage of proper roof venting is that it extends the life of the roof. If you do vent the roof at the ridge you should also add soffit venting at least equal in area to that of the ridge vent for proper air flow. See: http://www.roofhelp.com/ventilation_main.htm Almost totally non-applicable to the OP: * "Water vapor will condense..." Not in 0% relative humidity * "Frost will form....." In Tuscon? * "... problem of mildew..." Meh. * "Ice dams..." Again, in Tuscon? http://www.cor-a-vent.com/pdf/balancedventilation.pdf Commercial brochure on ridge vents. Good explanation (except for the bit about exhausting hot, HUMID, air). and http://www.energysavers.gov/your_hom.../mytopic=11390 Typical government simplistic check-list. Superficial, but good, suggestions. |
#21
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
"Swingman" wrote in message ... Snip .. Radiant barriers can have a significant effect on reducing solar heat gain on asphalt shingled roofs, not so much on clay or concrete shingles. Best is a product like "tech-shield" used as decking, better than none at all is the spray on radiant barrier paint. Keep in mind that you need at least 1" of void space below the radiant barrier for maximum effect. Radiant barriers do perform significantly better on vented roof systems. To add to what Swingman has mentioned here, my parents had the rediant barrier sprayed into their attic and had 8 more inches of insulation blown in. This was done last year in July. So far this year they have averaged a 20% savings in hours used on the months that they have been using the air conditioning. I can tell you right now that pay back will be a long process if you only consider your electricity savings to the cost of the improvement. I can tell you that you will probably save money on equipment repairs and or equipment replacement. The AC simply does not have to work as hard. My parents keep the thermostat at 76-77 degrees all summer long and the temperature stays there. Last year before the improvements the inside temp stayed at 79-81 degrees. Additionally there are no longer any "Hot Spots" in the house. Regardless of which room you are in the temp seems to be the same. Last, I built a wood and Hardiplank store room about 5 years ago. I chose to use Radiant Barrier Decking over standard Decking. The cost was about $4 per sheet more. The store room has one door that stays shut and no windows. It has sofit vents only. The store room does not feel any hotter in side than the out side temperature. IMHO well worth the small additional expense as Christmas candles do not melt nor do I when I am inside the store room. Basically, unvented roofs with clay or concrete tile shingles and R-19 insulation or greater; and vented roof systems, with mechanical equipment and ductwork within the conditioned space, and R-19 or greater ceiling insulation, perform the best in the Southwest. If you do decide on "e", your best bet for hot climates is a design that incorporates AC ductwork and air handlers within the building thermal barrier, and a vented roof with clay tile or concrete tile shingles and an R-30 or greater ceiling insulation. If the AC ductwork and air handlers must be located in the attic spaces, then go with a design that incorporates an unvented roof, creating a conditioned attic space for the mechanical equipment. Do your homework and find some "green" building seminars in your area ... the woods are full of them. -- www.e-woodshop.net Last update: 10/22/08 KarlC@ (the obvious) |
#22
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 3:56 pm, "HeyBub" wrote:
Almost totally non-applicable to the OP: * "Water vapor will condense..." Not in 0% relative humidity * "Frost will form....." In Tuscon? * "... problem of mildew..." Meh. * "Ice dams..." Again, in Tuscon? http://www.cor-a-vent.com/pdf/balancedventilation.pdf Commercial brochure on ridge vents. Good explanation (except for the bit about exhausting hot, HUMID, air). and http://www.energysavers.gov/your_hom...ling/index.cfm... Typical government simplistic check-list. Superficial, but good, suggestions. Heh, heh. Absolutely right, HeyBub. Mr Barss, There are some folks here with excellent ideas. Namely: Make sure you've got soffit vents if you're installing ridge vent. Make sure your insulation doesn't cover the soffit vents. If it's worth doing, overdo it (insulation- wise). I'm not sure about those radiant barriers, as the underside of the decking _must_ breathe very well. I roofed for twenty-plus years in MI, and I'm looking at re-doing my roof here in Tucson pretty soon. I'm probably going with painted standing seam metal. I wish copper was more affordable, or I was richer... Tom |
#23
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 17, 2:41*pm, "J. Clarke" wrote:
snip The channel from the soffit to above the insulation is easy--you get it in premolded plastic from Home Depot for not much money. It's called Accuvent. We installed a bunch of it on a current project. Local Home Depot didn't stock it, so had to order from HD online and pay some shipping. Neither Lowes nor Menards has anything like it. Goes up fast and will work with R30 easily. Highly recommended. Joe |
#24
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Wed, 17 Jun 2009 22:05:30 GMT, aemeijers wrote:
ransley wrote: On Jun 17, 1:06 pm, Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss Pay for an energy audit and get a blower door test done. There are many ways to increase efficency that will be outlined by an audit, you may find windows or another issue more important. Maybe Tucson is big enough so he can find somebody who will do that. I tried around here- none of the Utility, Insulation, or HVAC companies offer the service. I'd have to pay hundreds of dollars to have somebody come over from the Big City to do it. Inadequate attic insulation WILL be the largest heat gain that can be reduced economically. 15 inches of insulation and good ducted soffit vents with adequate roof ventilation (I'm partial to full length ridge vents for hot arid locations myself) is the best way to keep the heat out.. An insulated, reflective roof surface is a secondary method. Asbestos cement roof panels were very effective in Central Africa in the '70s - but are no longer an option here. Large overhangs to shade windows, along with properly installed Low-E glass will also help. Large roof overhangs also shade the walls (which should also be well insulated). Also a good idea to keep concrete driveways and patios well away from the house to avoid heat radiation and reflection into the house from them to a minimum. Grass isn't an ideal solution in Phoenix but is quite effective in reducing reflected/re-radiated heat. |
#25
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Andy,
More insulation, vent along the entire roof ridge, and vented bird blocks. cm "Andrew Barss" wrote in message ... I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss |
#26
Posted to alt.home.repair
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Swingman wrote:
Basically, unvented roofs with clay or concrete tile shingles and R-19 insulation or greater; and vented roof systems, with mechanical equipment and ductwork within the conditioned space, and R-19 or greater ceiling insulation, perform the best in the Southwest. If the AC ductwork and air handlers must be located in the attic spaces, then go with a design that incorporates an unvented roof, creating a conditioned attic space for the mechanical equipment. I find that very interesting. My attic currently has no venting whatsoever. It had a power vent which did not work. Good thing, as there were no other vents in the attic at all, so I guess it would have pulled air from the house. Here's the situation: 1500 sq ft home in North Texas DFW Hot, with high humidity Attic space is less than half the floor space, due to vaulted ceilings HVAC ducts are the accordion-style hoses in the attic. Insulation is older loose rock wool. Roof is painted metal over asphalt shingles. Almost all the attic space is shaded by overhanging tree branches. Soffit space with attic exposure is approximately 10 feet. Is it OK to leave this unvented? If I do vent it, I'll probably use a power vent and add a gable vent at the other end of the attic. I may also make it an operable vent, and add a 2nd operable vent into the living space to use it as a whole-house fan. Any reason that won't work? I realize I would need a tight-sealing grille into the living space. Suggestions welcome. |
#27
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
WhiteTea77581 wrote:
On Jun 17, 2:35 pm, Woody wrote: Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd go one better than just adding active fans at either end of the attic. I'd also add a whole house fan, mounted in the floor of the attic (ceiling of the living area) to pull cooler air up from the house into the attic. This air will be cooler than the outside air and will create a cool airflow throughout the house. Here's a fact sheet from consumer reports:http://blogs.consumerreports.org/fil...use-fans-1.pdf ~Mark. My parents had one of those in the 1950's before they had AC. In hot, humid weather the who house fan basically blows the hot air around. I think the goal is to blow the hot air out of the attic so it doesn't migrate into the house. Andy As hot air rises *and* the hottest air is in the attic, how do you propose it "migrate" to lower parts of the house? My understanding (and what I did via an attic roof fan) is to cool the attic air so that living spaces adjacent to it are not next to as-hot attic air and thus reduce the AC demand in those living areas. If there's one or more active fans on the attic vents (as I indicated and previous responder suggested) then the hot attic air would escape (i.e. be blown out) as cooler air, pulled into the attic via a fan entered. Thus lowering the attic air temperature. Thus lowering adjacent living space heat. Thus lowering AC demand. Thus lowering AC costs. Typically, these are thermostatically controlled so that once they reach some "reasonable" temperature level, you don't continue to blow living space air into them. ~Mark. |
#28
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
HeyBub wrote:
Nova wrote: For energy efficiency I would recommend more insulation above the ceiling rafters. Roof venting will lower the temperature in the attic crawl space but the main advantage of proper roof venting is that it extends the life of the roof. If you do vent the roof at the ridge you should also add soffit venting at least equal in area to that of the ridge vent for proper air flow. See: http://www.roofhelp.com/ventilation_main.htm Almost totally non-applicable to the OP: * "Water vapor will condense..." Not in 0% relative humidity I think people in Tucson still cook, take showers, etc. All produce moisture that will rise until stopped by a vapor barrier, often the roof. If there no venting... * "Frost will form....." In Tuscon? Although I didn't write the article I'll give you this one. * "... problem of mildew..." Meh. See cooking, showering above. snip -- Jack Novak Buffalo, NY - USA |
#29
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Woody wrote:
WhiteTea77581 wrote: On Jun 17, 2:35 pm, Woody wrote: Andrew Barss wrote: I'm looking for advice and ideas for improving energy efficiency in my house, especially heat from the roof and attic. I own an older house in Tucson, and we are trying to do what we can to decrease our electricity (mostly air conditioning) bills. The house has a peaked roof, with a low attic that has minimal access. The attic has some blown-in loose insulation between the ceiling joists, and nothing on the underside of the roof itself (and putting anything there is essentially impossible). We have some degree of venting -- there are small vents on the two end walls near the peak, and two passive vents (rotary type) on the roof, about four feet down from the peak. I've heard various things, some conflicting, about how to better the situation: a) blow in a lot more insulation. b) increase airflow using soffet vents (aka birdboard). c) do both d) do both, but with some sort of a channel up from the soffet vents to above the insulation. e) tear the roof off, put a lot of money into a high-tech roof treatment. The curent roof is light-colored shingles, and in quite good condition. Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss I'd go one better than just adding active fans at either end of the attic. I'd also add a whole house fan, mounted in the floor of the attic (ceiling of the living area) to pull cooler air up from the house into the attic. This air will be cooler than the outside air and will create a cool airflow throughout the house. Here's a fact sheet from consumer reports:http://blogs.consumerreports.org/fil...use-fans-1.pdf ~Mark. My parents had one of those in the 1950's before they had AC. In hot, humid weather the who house fan basically blows the hot air around. I think the goal is to blow the hot air out of the attic so it doesn't migrate into the house. Andy As hot air rises *and* the hottest air is in the attic, how do you propose it "migrate" to lower parts of the house? My understanding (and what I did via an attic roof fan) is to cool the attic air so that living spaces adjacent to it are not next to as-hot attic air and thus reduce the AC demand in those living areas. If there's one or more active fans on the attic vents (as I indicated and previous responder suggested) then the hot attic air would escape (i.e. be blown out) as cooler air, pulled into the attic via a fan entered. Thus lowering the attic air temperature. Thus lowering adjacent living space heat. Thus lowering AC demand. Thus lowering AC costs. Typically, these are thermostatically controlled so that once they reach some "reasonable" temperature level, you don't continue to blow living space air into them. ~Mark. Attic/gable fans can make a big difference in the Arizona desert, lowering the attic temperature form 150+F to closer to the ambient 115F summer temp. My unvented cardboard box solar cooker can reach close to 300F in the summer months. Was telling a former AZ resident about the solar cooker and he wondered why I bothered as I could probably accomplish the same thing by placing the cooking vessel in the trunk of the car... |
#30
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Soffit vents are 'required'.
Use the rigid foam panels that keep a clear air path over the insulation where it meets your walls. Also, if you use a swamp cooler, install a vented access door somewhere in your living space that vents into the attic. When the cooler is on, the air flows up into the attic (no need for an open window). With the cooler off, the vent flaps close and block attic air from returning into the house. A 'whole house fan' installed in the same way can be used to flush cool air into the attic in the early morning and flush hot air out in the evening. -Bruce Anyone living in the Southwest have advice on what the best move is? Thanks, Andy Barss |
#31
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
Bruce wrote:
Soffit vents are 'required'. Use the rigid foam panels that keep a clear air path over the insulation where it meets your walls. Also, if you use a swamp cooler, install a vented access door somewhere in your living space that vents into the attic. When the cooler is on, the air flows up into the attic (no need for an open window). With the cooler off, the vent flaps close and block attic air from returning into the house. A 'whole house fan' installed in the same way can be used to flush cool air into the attic in the early morning and flush hot air out in the evening. Where do you get those flap vents, and how well do they seal ? |
#32
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Fri, 19 Jun 2009 09:44:47 -0600, RB wrote
(in article ): Bruce wrote: Soffit vents are 'required'. Use the rigid foam panels that keep a clear air path over the insulation where it meets your walls. Also, if you use a swamp cooler, install a vented access door somewhere in your living space that vents into the attic. When the cooler is on, the air flows up into the attic (no need for an open window). With the cooler off, the vent flaps close and block attic air from returning into the house. A 'whole house fan' installed in the same way can be used to flush cool air into the attic in the early morning and flush hot air out in the evening. Where do you get those flap vents, and how well do they seal ? I can't find a manufacturers name on mine, but its aluminum and has felt seals at the edges of the slats. Sealing has never been a problem (no bugs or other things get back through), but during the winter when I'm not running the cooler, I place a plastic cover over the vent to stop all air movement. Here is a link to a similar vent: http://houseneeds.com/shop/vent/qmar...huttersbuy.asp |
#33
Posted to alt.home.repair,rec.woodworking
|
|||
|
|||
Attic Insulation and/or Venting in the Southwest
On Jun 19, 8:44 am, RB wrote:
Bruce wrote: Soffit vents are 'required'. Use the rigid foam panels that keep a clear air path over the insulation where it meets your walls. Also, if you use a swamp cooler, install a vented access door somewhere in your living space that vents into the attic. When the cooler is on, the air flows up into the attic (no need for an open window). With the cooler off, the vent flaps close and block attic air from returning into the house. A 'whole house fan' installed in the same way can be used to flush cool air into the attic in the early morning and flush hot air out in the evening. Where do you get those flap vents, and how well do they seal ? Google "upducts". Tom |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Attic Insulation and/or Venting in the Southwest | Woodworking | |||
Attic insulation: do attic floor, or roof, or what? And, how much work (ie $$$)? | Home Repair | |||
venting bath fan to outside from attic... | Home Ownership | |||
Can I use PVC for Bathroom venting through attic | Home Repair | |||
Attic venting question | Home Repair |