[Bryant]

If you wanted to reduce your electric bill and could only do one, which do you think would be more beneficial, attic insulation or radiant barrier installation? Thank you.

[mrdarcy]

I recommend that you call SECO, the electric company, and ask them this question. The builder who built my house in Atlanta suggested this to me and it turned out to be an excellent suggestion. SECO is a cooperative and although they sell electricity, they really are interested in helping customers conserve energy. Plus, they are most knowledgeable about the central Florida climate and seasonal energy needs.

[TimeForChange]

I spent 35 years in the roofing and insulation business with a major company. There are three ways to retard heat flow..(conduction, convection and radiation). The best and cheapest way to insulate a residential structure is to add fiber glass insulation to your attic. The cheapest is blown in. Attaching radiant barriers under your roof deck or draping it under the roof deck is good but more expensive. Also it will cause the roof deck to absorb the heat more thus the shingles on your roof will be several degrees warmer. That will cause the life of the shingle to lessen.

[DangeloInspections]

The short answer to your question is adding blown in insulation. Without posting links, etc, I'll simply say that adding a radiant barrier after your home is built is quite costly and almost impossible to do without trampling your existing insulation.

Radiant barriers can easily cost $4000-$5000, not including the cost to reblow more insulation over the trampled insulation. Despite what some contractors may tell you, engineering studies have found that the typical savings gained from this is usually 10-12%. Let's say your total Electric bill is $150 per month. That would be $1800 per year. 12% of that would be $216 per year savings. This equates to a payback time of 23 years......more than most Villages homeowners would be comfortable with.

Now...understand that if you are building a NEW home and use the radiant type roof sheathing DURING the build, this IS a good idea as it is done much more cheaply, does not hurt the insulation, as it is not done as an aftermarket add on.

I think the better option for an existing home is adding more insulation. The typical cost for blown in fiberglas insulation is $75.00 per bag installed. Adding an additional few inches or so can start saving money quite quickly. The typical villages newer home is insulated to R-30. Some other surrounding communities insulate to an R-38. While there is a point where more is not really better, getting to an R-38 is not that expensive, and one would see a payback in a relatively very short time. This would also be much less expensive to do. There are many local insulation contractors that can do this.

Hope this helps!

[Arctic Fox]

Originally Posted by DangeloInspections

...if you are building a NEW home and use the radiant type roof sheathing DURING the build, this IS a good idea as it is done much more cheaply...

what would likely cost be if you have it done when you get a new roof?

thanks

[DangeloInspections]

Originally Posted by Arctic Fox

what would likely cost be if you have it done when you get a new roof?

thanks

The cost would be moot, because it simply would not work and could actually hurt, if you are referring to sandwiching the foil between the shingles and the sheathing. If you are thinking of replacing the sheathing with new sheathing, it would still be very costly.
Here is a link;
Radiant Barrier Under Shingles Scam | The Radiant Barrier Guru
Can I use AtticFoil(R) Directly Under My Shingles? | AtticFoil(R) Radiant Barrier - Do-It-Yourself Professional Grade Radiant Barrier

[Chellybean]

Originally Posted by DangeloInspections

The cost would be moot, because it simply would not work and could actually hurt, if you are referring to sandwiching the foil between the shingles and the sheathing. If you are thinking of replacing the sheathing with new sheathing, it would still be very costly.
Here is a link;
Radiant Barrier Under Shingles Scam | The Radiant Barrier Guru
Can I use AtticFoil(R) Directly Under My Shingles? | AtticFoil(R) Radiant Barrier - Do-It-Yourself Professional Grade Radiant Barrier

Thanks Dude always wanted more info on it.

[Chatbrat]

Considering the average age of people who live in TV and those moving here--don't worry about saving money, worry about living long enough to enjoy what you have

and if you're smart enough you can make more money in retirement than you can have made while you were working

My mentor told me do not worry about saving money , worry about making money

Take the $$ you would put into insulation & invest it smartly you will be way ahead of the game

[bbbbbb]

Well here are some items to ponder: If building a new home, framed with a raised foundation, use R24 under the floors, R19 in the walls and R38 in the ceiling. I like batts because they do not compact, they are easy to work around if you do any attic work, electric etc. Plus with batts, you can see them they are constant thickness and some firms will claim they blew in x inches, do you think you will go up there and measure all of it.???
OK, we had the radiant sheets put up in Atttic. House and Garage. It cost about 1K and it was really worth it. On a hot day say it is less than 90, we do not need the air conditioner. When Bill finished the attic radiant barriers, we saw an instant change for the better in the house because the weather was mainly constant for a few days before and after and we could actually feel the difference. The radiant barrier is not at the shingles, it is inside the attic, a good installer does it all in about 3 hours. We had ours done by BILL MCKENZIE FROM GABLE INSULATORS. My major was heat transfer and I seriously doubt that this will affect the shingles, because most all of the heat into the shingles is radiant energy, not conduction and not by convection, so the radiant energy comes from the sun and the new barriers are inside the roof sheeting in the attic. We really believe in them for sure.

[ColdNoMore]

Originally Posted by Chatbrat

Considering the average age of people who live in TV and those moving here--don't worry about saving money, worry about living long enough to enjoy what you have

and if you're smart enough you can make more money in retirement than you can have made while you were working

My mentor told me do not worry about saving money , worry about making money

Take the $$ you would put into insulation & invest it smartly you will be way ahead of the game

Great advice.



Analogous to that is a bunch of people I know who shake their head that I chose to carry a small mortgage on my house, instead of just paying for it with all cash.

Even when I show them on a napkin that the money that would be used to pay off the mortgage is making much more being invested, they still don't get it.

One of these braniacs recently had to go back to working part time to make ends meet, after paying cash for a $500K house.

He then got mad at me when I quickly showed him what a 30 year mortgage would be on $100K and with the magic of compounded interest, what he would have in his savings account right now had he put the $100K to work 10 years ago.

He really got mad when I showed him what the DJIA has done in the last 8 years....LOL

[tommy steam]

I tend to believe what a professional inspector ,D'Angelo has to say .

[bbbbbb]

OK how about this?

If you buy and pay for a house on a 30 year mortgage, depending on the interest rate, you will eventually pay about twice the home price for that home.
Consider this, when we got married, 41 years ago, my wonderful wife and I agreed, never to pay interest on anything. In all these years, we have not paid one dime in interest, nothing. We save for what we want it and buy it. Once, I wanted a new car, so we picked it out and wanted to pay cash, no one in the agency knew how to handle a cash payment for a new car!!! They took a copy of my drivers license, they gave me the keys and told me to come back and pay the owner in one week because he was on vacation; only he could manage a cash payment.

[bbbbbb]

Here is an insulation reply. It is true, three forms of insulation, conduction, radiation and convection. Look it up, interesting to follow that. Yep that was my major and MS degree.
OK, Radiant blankets stop the heat flow into the attic. On insulation, I like batts because you know what you have, on the truck the batts will be rated at about R 38 the R value is the numerical identity of the resistance to heat flow and this is a bit complex.
With blown in, OK there is so many cubic feet of loose material to blow in, when it is done, you would have to go up in the attic, straddle the stringers on the trusses and measure, I do not think you want to do that. With a flashlight you can see all the blankets side by side and they are hopefully about R 38. Loose insulation will settle so even if 10 inches or so is blown in, it will settle in time. One person was concerned about stepping on it in the attic, well, no way, no insulator will do that because if he does, he will go through the Sheetrock and into the house, straight down. They stand on the stringers. So, we had the Radiant sheets added by Gable Insulators, Mr. Bill Mc Kenzie, a great person, a good installer and we IMMEDIATELY could see the improvement in the home comfort.
Another good feature of batts and radiant is that if you want to do any attic work, vents, wiring, storage, it is much easier to do. Good luck. bbbbbb

[DangeloInspections]

bbbbb,

Wow, sounds like you got a great deal on a radiant retrofit. I have been repeatedly told the cost was typically much higher.

I have nothing against Radiant...as long as it is installed properly.

Since this forum is mainly for The Villages, I usually limit my comments to be pertinent to Villages homes. For at least the past 5 years or more, The Villages insulates the attic area to an R-30. I like to see more, but that meets code, and that is what they do. For Designer and Premier homes it is mostly blown in fiberglas. For Villas and some cottage type homes it is R-30 batts.

I am in attics everyday in The Villages, walking all around them. As you correctly stated, I walk on the bottom chords of the trusses. Knock on wood, I have never mis-stepped and I am in over 400 Villages attics a year.

I do find that the attic temps in attics that have a radiant barrier are cooler. My only caution has been;
A) The high cost.
B) The usual trampling of the blown in insulation when the panels are installed in a pre-existing home.
C) The very long payback based on a 10-12% cost savings.

You avoid all of these when the builder uses radiant sheathing during the build.

the only other negative I have been told about has been the problems with attic antennas and cell phone call quality. Having Wi-Fi cell phone calling would solve the latter.

Frank