Guff
Premium
join:2001-12-30
CheckYourSix | reply to Billusa
Re: So I want to get my attic insulated...
Yeah, whatever, man. So I said heating bill when energy bill would have been the proper term. Just what this world needs. Another Sgt. Grammar in a dead forum.
--
"Gentlemen, prepare to defend yourselves!" |
|
Billusa
join:2000-03-08
Dallas, TX
 ·AT&T Southwest
1 edit | reply to Guff
RE: "There's enough data collected to have people make up their own mind without the sales pitch by an installer. It's nothing new under the sun that barriers will cut down on your heating bill..."
Wrong -- there you go again.
From the link above (Radiant barrier gfact sheet):
"Radiant barriers reduce the amount of energy radiated from the top surface of the insulation, but can also reduce beneficial heat gains due to solar heating of the roof. The net benefits of radiant barriers for reducing winter heat losses are still being studied. "
Therefore, one cannot state that an RB will cut down your heating bill, because they haven't done any conclusive studies to even show it keeps any appreciable heat in your house to begin with! |
|
Billusa
join:2000-03-08
Dallas, TX
·AT&T Southwest
2 edits | reply to Guff
said by Guff  :said by Billusa :Molecular friction stopping RB's -- I couldn't stop laughing when I read that part in the "Google expert's" post! Obviously you've forgotten your laws of physics. Radiant barriers stop/slow the transfer of radiant heat at the molecular level. Period. It's the very definition of ALL radiant barriers, not that they reflect heat. Reflection is a property of light. Try studying heat convection, radiation and conduction. NO, I have not forgotten my physics. I was laughing, and am still laughing, at such an explanation. EVERYTHING happens at the molecular level, EVENTUALLY! For example, at the molecular level, there's more empty space in your head than actual brain molecules, too. That's a fact of physics, also.
It's a lot easier to simply say that that RBs stop the transmission of radiant heat into the attic. And that insulation stops the tranmission of conductive heat through the attic floor.
One doesn't need Google and Einstein molecular physics quoted in order to help a layman understand what to do with RBs vs. insulation. You started off your post with "Bottom line, they do work as advertised." Then did absolutely nothing to quote any before/after facts or stats to back up that claim. Nothing.
My post stands as is. |
|
Guff
Premium
join:2001-12-30
CheckYourSix
| reply to TexasPlus
said by TexasPlus :As a matter of fact, I have been looking at this in depth for the last three years.  But not only on line behind a monitor. So have I. I simply stated that to make you and other folks do your own homework vs. settling on comments/recommendations made by people posting. Looks like you've done some legwork. And yes, my previous post is vague in spots. My apologies. The older I get, the less patience I have to type long sentences. I am no expert in this field, but I don't think this field need experts. There's enough data collected to have people make up their own mind without the sales pitch by an installer. It's nothing new under the sun that barriers will cut down on your heating bill, but there is no magic bullet. Except maybe an igloo made of carbon dioxide.
--
"Gentlemen, prepare to defend yourselves!" |
|
Guff
Premium
join:2001-12-30
CheckYourSix
| reply to Billusa
said by Billusa :Molecular friction stopping RB's -- I couldn't stop laughing when I read that part in the "Google expert's" post! Obviously you've forgotten your laws of physics. Radiant barriers stop/slow the transfer of radiant heat at the molecular level. Period. It's the very definition of ALL radiant barriers, not that they reflect heat. Reflection is a property of light. Try studying heat convection, radiation and conduction.
--
"Gentlemen, prepare to defend yourselves!" |
|
twojciac
join:2003-05-22
Sachse, TX
| reply to Billusa
The thing that has always made me suspicious about the spray on radiant barriers is that the companies offering them always seem to try to get you to make multiple changes at the same time when they spray. They want you to spray, change your vents, and add 6" of insulation.
So... what made the difference in your power bill? Probably the vents and insulation, with some effect from the RB spray. |
|
Billusa
join:2000-03-08
Dallas, TX
·AT&T Southwest
| reply to bendejo
said by bendejo :US Department of Energy Fact Sheet on Radiant Barriers: » www.ornl.gov/sci/roofs walls/radiant/rb_01.html That's a good place to start.
Molecular friction stopping RB's -- I couldn't stop laughing when I read that part in the "Google expert's" post!
If you are due for a new roof, and have the bucks, a metal roof can also be a good investment. Their combination of emissivity and reflectivity will act as an effective RB. They also offload heat a night waaaaay faster than shingles, which act as a heat sink with all that asphalt in them.
You will also get up to a 25% reduction in your homeowner's policy in TX. That's what we did on our new home 2 years ago. We used Mueller.
I have never seen a before/after study where a spray on RB came anywhere close to matching a deck-based RB or the foil. And I have been following this subject for almost 3 yrs -- before we built. Efficient Attic -- and the others -- have no scientific, verifiable data. They simply say "save up to xx%." The emissivity of a spray on RB does not even come close to foil or RB roof decking -- period.
Spend as much as you can insulating and venting your attic first. That will give you your biggest bang for the buck and keep your house coolest. If you do that effectively, then reducing attic temps will be a lesser requirement -- if at all.
You live in the house -- not in the attic. |
|
bendejo
Bendejo
join:2003-02-12
Plano, TX | reply to TexasPlus
US Department of Energy Fact Sheet on Radiant Barriers:
»www.ornl.gov/sci/roofs+walls/rad···_01.html |
|
TexasPlus
join:2004-06-16
Bedford, TX
 ·Millenicom
 ·ViaTalk
| reply to Guff
said by Guff :Easily done. Do what I did. Go to google.com Type in "radiant barriers facts" Read through some of the more than 200,000 hits. Take your time, you seem like the type that needs it. As a matter of fact, I have been looking at this in depth for the last three years.
But not only on line behind a monitor. I have crawled around many attics looking at good and bad RB installations, I have attend several seminars on the subject, and have talked with installers, and manufactures. I have educated myself enough that I can now easily spot the BS and separate a lot the myths from the facts. This self eduction on RB, and attic ventilation started out just for my own use, but is now aiding me in helping some customers, as I grow a new business.
said by Guff :I'll let my weaker side prevail and simply state that I claim none of the information I presented as facts, Fair enough.
said by Guff :As far as using both sheet-type and coating-type barriers, you misunderstood. Used together, use sheets on the roof deck, coating on joists. OK, but that is not the way it was originally presented, in light of the fact we were talking about retrofitting an existing structure. While "coating on joists" may have some small additional benefit on a new home with RB sheets on the roof deck, the return on investment on doing both as a retrofit just is not there. However I can see possible economics in mixing both types, IE foil sheets stapled to the underside rafters, with the foil facing the open air space in places it is easy to get to, and spray on coating where it is hard to get to. The manufactures info generally shows that the foil is about 20% more efficient than the spray coating.
said by Guff :As far as air circulation goes, yes, you would have moisture problems without air circulation year round. Re-read what typed. "Controllable air movement or lack thereof". If you don't have good ventilation in the summer, you'll retain heat. Too much in the winter and you'll lose heat. This is regardless of your insulation status. "What typed" by you was:
said by Guff :"The air molecules need to be released in the summer and retained in the winter." And there is a huge problem with the last part...if you retain the air, you will retain the moisture.
For example the folks that put bags over turbine ventilators in the winter time are very likely to retain enough moisture in their home to have future mold problems. The small amount of money saved on heating is far outweighed by the eventual costs in health problems and expense of creating a "sick building" through mold growth.
--
"The world is a book; those who do not travel read but a single page." -St. Augustine |
|
Guff
Premium
join:2001-12-30
CheckYourSix
| reply to TexasPlus
Easily done. Do what I did.
Go to google.com
Type in "radiant barriers facts"
Read through some of the more than 200,000 hits.
Take your time, you seem like the type that needs it.
As far as you're doubting of the accuracy of my post, you're entitled to do so. Although my nature is too flame you because in essence you are calling me a liar, I'll let my weaker side prevail and simply state that I claim none of the information I presented as facts, just a generalization of other people's "facts" posted on-line. As far as using both sheet-type and coating-type barriers, you misunderstood. Used together, use sheets on the roof deck, coating on joists. As far as air circulation goes, yes, you would have moisture problems without air circulation year round. Re-read what typed. "Controllable air movement or lack thereof". If you don't have good ventilation in the summer, you'll retain heat. Too much in the winter and you'll lose heat. This is regardless of your insulation status.
--
"Gentlemen, prepare to defend yourselves!" |
|
TexasPlus
join:2004-06-16
Bedford, TX
·Millenicom
·ViaTalk
| reply to Guff
Please supply some reference for your information. I have some serious doubts about the accuracy of much of your post.
Such as where you said
"I would actually recommend the use of both because the coating can be applied to every surface, whereas the sheets usually need to stay flat/rigid.
But a big part of the equation is controllable air movement or lack thereof in the attic. The air molecules need to be released in the summer and retained in the winter."
Two layers is only going to reflect the energy back and forth between them, and second you must have ventilation of the attic space year round or you going to have moisture/mold problems period, no if and or buts about that!
--
"The world is a book; those who do not travel read but a single page." -St. Augustine |
|
Teasip
join:2001-05-14
Plano, TX | reply to Redshirt 24
Interesting read. Thanks. |
|
Guff
Premium
join:2001-12-30
CheckYourSix
| reply to Redshirt 24
Just a little info for those inquiring about the radiant barrier coatings. Bottom line, they do work as advertised. First notice that most are made with reflective/metal particles, then there are some that use hollow spheres. Both are suspended in a paint coating for ease of application and uniformity when dried. The way they work is somewhat misleading, even the installers usually get this part wrong. What actually happens is the metal particles or hollow spheres form continous film. The metal particles plates, or, in other words, overlaps each other. The spheres lock into one another similar to what a styrofoam ice chest looks like, but more on a microscopic level. These "barriers' formed are very tight, with litle space between the particles.
Visualize a sponge, a brick and a block of marble. You can see the "porosity" or openess of the sponge, and somewhat less on the brick, and basically none on the marble. Compare these to grades of insulation and a radiant barrier coating would like the marble, a very light, tight, rigid film. It's the tightness of the film that let's it "radiate" heat without the bulk of traditional insulation. Most people including the guys putting it in think radiant barriers reflect heat like a mirror reflects light. Wrong analogy. The barrier film inhibits molecular friction caused by radiant energy. Radiant energy is what you feel when your outside on a cool day, but yet in the sunlight you feel warmer. Step into a shady area and you feel cold again. The air temperature changed little if any, and yet you feel the difference. That's radiant energy at work. It causes friction at the molecular level. Radiant barrier coatings inhibit this friction. Now, back to the analogy of sponge, brick, marble.
Sponge = standard insulation
Brick = blown in expanding insulation
Marble = radiant barriers
Coach P's estimates are fairly accurate, the sheet type barriers usually do better than the coatings, if they are installed tightly. I would actually recommend the use of both because the coating can be applied to every surface, whereas the sheets usually need to stay flat/rigid.
But a big part of the equation is controllable air movement or lack thereof in the attic. The air molecules need to be released in the summer and retained in the winter.
As a bit of trivia, these types of coatings have been around for ages. Where they got there start is in the remodelling/repainting of houses or buildings that had caught fire. The industry standard for sealing off the smoke damage on structural wood and siding has always been ready-mixed aluminum paint. The plating action of the metal particles locked out the smoke smell. Guess what part of the house has the most wood exposed to smoke? Well, since smoke rises, you'd have to say the upper part, ie. the attic. People started to notice that the structures painted with the aluminum had less heat transfer. And so a new market was born. |
|
Coach P
join:2007-07-07
Plano, TX
| reply to Teasip
With our house layout the ridgevent is near the very front over our bedroom and the power vent is in the back of the house. We have like 30 soffit vents cut around to allow greater air flow.
I know they say dont mix but thats what Ameritex roofing recommended in our roof situation. And actually its only about 8 ft of ridgevent. They did remove the static vent that was just below where the ridge vent went. |
|
Teasip
join:2001-05-14
Plano, TX | reply to Redshirt 24
Good information. Now I'm going to check my soffit vents to make sure that they are adequately open for my turbines. |
|
TexasPlus
join:2004-06-16
Bedford, TX
·Millenicom
·ViaTalk
| reply to Coach P
said by Coach P :We also added about 12 ft of ridge vent and one power vent. Ouch!!!
I have been doing some research in preparation to have ridge vents installed, and most of the sites I have seen on attic ventilation warn strongly against mixing types of ventilation.
The problem is when you mix types, you get airflow from one type of vent directly to the other type of vent, greatly reducing or eliminating the airflow up through the soffit inlet vents. When this happens, you have dead air areas, moisture is not vented out, and mold growth is enhanced.
A couple of the sites had dramatic pictures of mold damage caused by mixing vent types.
Some links from a quick goggle just now on "mixing attic vent types".
»www.ronhungarter.com/black_mold.html
»www.airvent.com/pdf/literature/W···Know.pdf
»www.airvent.com/homeowner/resour···ng.shtml
»www.fourseasonsroofingandsiding.···tion.htm
»www.blocktheheat.com/ventproblems.htm
»www.lomanco.com/ventilationFAQ.html#19anchor
--
"The world is a book; those who do not travel read but a single page." -St. Augustine |
|
Coach P
join:2007-07-07
Plano, TX
| reply to Teasip
We we got our first bill with the barrier being added. It was $10 less then June's bill. We didnt change anything on the thermostat and yes July was warmer than June.
So hey I can live with some savings...it will be interesting to see what August will bring.
I also looked back at last years bill for July and it was dramatically lower, but we didnt have the rain and was already at 100 temps. |
|
Teasip
join:2001-05-14
Plano, TX
1 edit | reply to Redshirt 24
»www.oncor.com/electricity/teem/default.aspx
Select for consumers and poke around. They have a page that lists the eligible upgrades. I've got my evaluation scheduled for 8/8. |
|
KMB
@swbell.net | reply to Teasip
Can you tell me which WFAA article on Oncor you saw? Had a friend who mentioned a similar energy efficiency program, but not sure how to find details or what kinds of costs it covers. Do you have contact info for the program? |
|
Teasip
join:2001-05-14
Plano, TX
| reply to Redshirt 24
I just read a story at the WFAA website regarding the energy efficiency program through Oncor and how they may cover all or part of the costs of improving your residential energy efficiency. I would like to contact one of the local companies and at least get an idea as to cost for my 2100 sq. ft. residence here in Plano. |
|
