Anyone have radiant barrier on roof? Does it work?

Had it put in when we had our roof replaced in 2009. I do believe it has contributed to lower electric bills. I don't think it's enough on it's own. We went with a lighter color shingle, the radiant barrier, and ridge vents. With all of that, it lowered our bill by a decent amount.

My a/c is now 18 years old. I wish it would die while I have a home warranty.

 

you gotta be sly and kill it

 

I'm getting ready to have our roof replaced (hail damage), and would really prefer a charcoal colored shingle, as it would look terrific with the brick we have, but am concerned about the electric bill, of course. We're getting ridge vents, and the guy is going to give us an estimate on a radiant barrier when I talk to him Friday, but I expect it to be more than I want to shell out (the roof is only going to cost us a $500 deductible, but the radiant barrier is something we have to pay for ourselves). Has anyone replaced a roof with the same quality shingle, the same color, and the radiant barrier, and had an improvement with their electric bill? Of course, my water bill is usually more than my electric bill during the summer, at least where I live in Austin. It kind of freaks me out, but water is expensive here.

 

I live in Austin and have a tile roof...we put in a radiant barrier when we renovated and the guys working in the attic had never done it before (we bought the foil from home depot, some staples, etc). They commented that the attic was much cooler after it went in. If your house has ridiculous amounts of attic insulation (think like R-60) then the benefits are negligible since the heat doesn't really make it to your house (though your A/C equipment up there would bake a bit (but that is usually insulated too).

Anyway, its a no brainer to get it put in as far as I'm concerned. We're building a new building here in Austin and we're doing both the radiant barrier (its very very cheap for new construction since it comes attached already to the roof decking), reflective shingles (though they are still gray), and R-60 in the attic.

 

Also did foil stapled to roof deck. Before hand, AC would not keep up getting as hot as 80 and would run for hours after the sun went down to catch back up. Now my AC keeps up.

I used an IR thermometer and the deck pre and post install was 29 degrees cooler. The air temp in the attic was like 18 degrees cooler after installing the foil.

Don't do the spray-on barier (factory spray on the deck or aftermarket) ...it isn't as effective. Google it. Foil is FAR more effective and lasts longer.

Even if you have R60 insulation, it will still help because your AC ducts are still exposed to the heat in the attic as well as the unit itself. The AC system will run more efficiently because the ambient temp is lower.

 

I question how much effect it really has on reducing electrical bills. Obviously, the non-paint foil applications are your best bet. But, I think more importantly is just being on top of who your energy provider and making the switch to the best yearly deal whenever your contract runs out. That's going to save you more money than any radiant barrier. You will probably really never know when you actually pay off what you paid to have it installed and, if the savings are marginal like I expect, it could take years. It's almost the same debate on whether it is cost-effective to buy an electric (or green) car at this point. Past studies have shown that even with gas in the $3-4 range per gallon and given the extra amount of money you have to pay to get one given the life expectancy of the car, you will be lucky to break even and it is better to pay for a gas car.

So, per the money aspect, count me as a skeptic. It may save you some money over the long run but is it really substantial enough to pay off the costs to put it in and reap monetary benefits? That said...the foil installs are more expensive than the paint jobs. But, the paint is less effective.

If you are lax about researching and switching energy providers to the best deal you can find out there, then I would address that first cause that is where real money savings are. Assuming you are on top of that and feel you can do better with radiant barrier/home comfort levels/etc., then explore the radiant barrier option. You could also look into window solar screens if you have a lot of windows. I personally considered the radiant barrier before but now my bill is so low (from my vantage point) I don't see a reason to bother. But, we all have our own unique situations when it comes to how much were home, how much energy we use, etc. . Your situation may not be about money as your house isn't cooling down below 77 degrees. It makes me question whether you have enough insulation or how old the house is...cause that should not be the case if your a/c is working properly.

 

I just did the paint and insulation thing a few years back and even that seemed pretty effective.

 

From talking to people, the ridge vents are what really makes a big difference. I'm guessing the radiant barrier wouldn't hurt to do.

 

I have it in my house, which is only about a year old. I can leave the AC off all day and the temp never goes above 77. Even in the summer.

 

at my house we got it done before the summer, I don't know about the electric bill, but I noticed a great change in one of the rooms that would normally stay hot as hell in the summer and cold as ice in the winter..

 

it probably helps if you guys say whether you have foil or paint when you are describing how well it works for you. just so we know if paint is working for a lot of you...cause there have been complaints that paint sucks in the past from what i've read. but, not all paint is the same obviously.

 

Mine if foil and it was installed while building the house.

My in-laws got the spray and their bills haven't really changed since they got it a year ago.

 

Had my dad install the foil barrier and the attic does not get as hot as pre-foil. Bills went down but I also did Hunter Douglas Duette Honeycomb shades on the windows and had GreenFiber Cellulose blown in insulation added as well as recycled blue jean insulation (http://www.bondedlogic.com/) where I have decking.

 

I still have this problem but I believe it's due more to the age of my a/c unit than anything else at this point.

 

I got mine done from EAS two summers ago. I think Home Depot can get you a interest free deal for 12-18 months. My house is 3400 square ft, built in 2008. My highest electricity bill was $165 last july or august (remember the 90 day drought). It averages around $120s during May-Sept. During the fall and winter, my bill is around $50-75.

In the summer, I keep my house at 76 degrees while I am at work and 72 degrees when I am home.

I paid $1,100 for the radiant barrier and extra insulation. The salesman from EAS will come out and quote you $2500. Say NO. Then, he'll give you a quote around $2K. Say NO. He will give you 2 more quotes. Say NO. Finally, he will ask you how much are you willing to pay. I told him $1K. Then, he does some math and says ok.

I ask him estimate what is the % I lost in instulation for cutting the price. Dude told me 3%. I was thinking "you bleeping jacka$$ tried to rip me off."

bottom line, i think it helps a lot because my bill was close to $300 before radiant barrier. I did not get the solar fans as I read on CF that it was not worth the extra money. My mindset was I can add this cost to my selling price if I decide to sell my house one day. However, extra money spent on electricity is variable cost and cannot be regain.

 

Interesting info, guys. Thanks!

 

For the uninformed (me) What or who is EAS ?

Thanks in advance

 

Efficient Attic Systems....I think they use the spray. My attic is silver, but i do not see any foil. I read on CF 2 years ago that the spray has improved since the early days. I confirmed that with EAS before doing the deal. They also added insulations foam too.

On another note, my father in law in Louisiana gave the WORKERS, not contractors, an extra $100-150 on the side. They gave him an extra 20 layers of insulation. Food for thought.