From the front lines of your attic - advice, tips and happenings to help homeowners reduce utility bills through efficiency retrofits and renewable energy.
We have been getting lots of questions regarding radiant barrier products. Radiant barriers seem to make sense to reduce attic temperatures in the summer. You may have seen the home show demonstrations where one side of a mock attic has a high pressure sodium lamp heating one attic with radiant barrier, and one attic without radiant barrier. These are very convincing demonstrations that you can actually feel or see the temperature differences. So does a foil radiant barrier product work?
Let me give you a background of where we are coming from as a US EPA Home Performance with Energy Star energy auditor and contractor. We use a science based approach to reduce your energy bills and make your home more comfortable. That means our recommendations are based on a comprehensive energy audit using a blower door, thermal camera, energy modeling and heat transfer principals… not on a PowerPoint Presentation someone developed who probably is not an energy auditor. We have performed hundreds of APS energy auditsand SRP energy audits so we have some experience under our belt and seen the benefits and a home that performs well, and the broken promises that are not only costly but bring down companies that do quality work. So let’s get back to your question.
Here are the facts -
1. In Phoenix, with 360 days of sun a year, in a house with minimal insulationyour home is only getting a maximum of 20% heat gain from the attic. We have written about the importance of your insulation being installed correctly in a previous post. The majority of your heat gain is through the windows.
2. Using the most outrageous radiant barrier savings claims of a 30% cost savings onyour heating and cooling bill (sometimes even the sales rep gets confused and says it’s 30% of your total bills), let’s do the math. I’ve provided a radiant barrier savings calculator you can use to get accurate estimates on your savings below, just enter in your highest summer electric bill. Let’s say that’s $300 and 50% of that is from cooling. So that means you are spending $150 on cooling for, let’s be generous and say May, June, July, August, September (5 months). $150 x 5 months = $750 on cooling (overestimated). Then we’ll find how much of your cooling bills is from the attic (20% from #1 above) by taking $750 x 20% = $150. Now take 30% of $150 = $45. That’s your annual savings from radiant barrier, $45!
3. If you are spending $2,000 on a radiant barrier to save only $45 a year, there are much better ways to save money on your bills! One would be to install a solar hot water or even solar electric system for a much quicker payment and ROI. That is why we will never recommend a radiant barrier product without tacking the big items found in a home energy audit first.
We hope that helps and feel free to leave comments below or like us on Facebook for a free Energy Savings Guidebook to learn how you can start saving today.
During my APS energy audits and SRP energy audits I occasionally run across a home that has high utility bills but as I am going through my inspection of the air leakage, duct leakage, insulation, room pressures, HVAC system and ductwork there is not a huge problem identified. In one SRP home in Gilbert, I fell back on the homes motors, pumps and appliances and started exploring other options to pinpoint the cause. During this home’s SRP energy audit the homeowner informed me that she was running the dryer three to four times just to dry a load of laundry. It can be frustrating when it takes longer to dry your clothes than it does to wash them, especially if you have a couple loads of laundry to do. I know what that’s like, having bought a 1995 home in Phoenix with all original appliances. I hated having to run my dryer 3 or 4 times just to get my clothes dry! If you are in the same situation or you may even have a new washer and dryer set – before you go out to buy a brand new dryer here is a quick tip I found can save you literally hundreds a year on drying costs.
Your dryer is actually the second biggest energy using appliance after the refrigerator. Plus if you are having to run the dryer twice or more to get your clothes dry then it is using even more energy. The washer actually doesn't use that much energy, the costs for the washer come in when it needs to use hot water (try buying cold water detergent and seeing how your clothes come out). Your dryer vents can be anywhere from a couple inches to 20 feet of ducting to get to the outside. All that ducting collects lint inside and could clog the vent and decrease the efficiency of the dryer. By cleaning dryer vents at least once a year you will increase the efficiency of the dryer and help prevent the risk of fire. A good way to clean the dry vent is to use a shop vac or leaf blower and suck all the lint outside. You want to be sure to snake the whole system to prevent a buildup.
In this case the SRP energy audit recommendations was mostly around the home’s pool pump run time, recirculation pump, 4 combined refrigerators and freezers and the clogged dryer rather than construction defect upgrades. This homeowner was still able to take advantage of the SRP rebates available for the variable speed pool pump and the refrigeration recycling program as well as the duct sealing rebates.
Air conditioning in Phoenix accounts for up to 60% of a home’s annual electricity costs. It is not uncommon for energy bills to double in the summer time in Phoenix even if a homeowner tries to manage his or her energy use by switching to the APS and SRP time of use plan, only doing laundry and running the dishwasher at night, and setting the thermostat up during the day. Here are seven ways you cans save on air conditioning costs without spending thousands of dollars replacing your AC unit with a high efficiency unit.
Air Conditioning Saver #1 - Leave your doors open
No, not your exterior doors but your interior doors. Phoenix air conditioning companies have spread a lot of false information out there about closing your vents and doors. You want all the interior doors open or at least cracked to help circulate air back to the return. Here is a quick test you can do to check if your air conditioning costs are higher than they need to be. With the air conditioning on close a bedroom door and place your hand under the door to check if you can feel air coming out of the door. If you can feel air escaping, your room pressures are likely to be unbalanced every time the door is closed. Have an APS Home EnergyAuditor or SRP Home Energy Auditor do a home performance assessment of your home to actually measure the pressure in each room to determine if correction is needed.
What if you have teenagers or relatives are staying over or you have dogs that you don’t want in a room so you have to keep the door closed. Your energy auditor will probably recommend a transfer grille or jump duct be installed to relieve the built up room pressure and can go over the options with you.
Air Conditioning Saver #2 - Seal the ductwork.
Between 20% to 30% of an average home in the metro Phoenix area is wasting conditioned air in the summer and heated air in the winter to the attic. If 60% of your energy bill in the summer is from air conditioning and 20% of that air is not being delivered to the rooms it needs to go to, that can add up to quite a bit of change over 5 years. HVAC contractors do not seal the ductwork even on a new, high efficiency air conditioner which is like driving a Prius with a hole in the gas tank. Sealing your HVAC ductwork not only saves money on your heating and cooling bills, it brings less dust in the home too.
Air Conditioning Saver #3 - Air seal your home.
Making sure your exterior doors are well weather-stripped, air sealing any electrical and plumbing penetrations and sealing any recessed canned lights will help keep your conditioned air inside and the outside air outside. A leaky recessed canned light can increase heating and cooling bills by as much as $5 to $30 per canned light. Air sealing your home will also help stop the stack effect which causes warm air to rise and cool air to enter the home. If you have a wood burning chimney, a chimney pillow will help stop heated air from escaping in the winter and save on your winter heating bills. If you only have some areas of doors that you can see light through there are easy upgrades you can do with filler weather-stripping to fill those voids without replacing your doors. I know what you are going to say, don’t houses have to breathe? Yes, you need to have a supply of fresh air into your house for health and safety concerns but it is better to seal your home as tight as possible and bring controlled ventilation in from the outside than live with a leaky home and rely on dirty attic air as your “fresh air” for the house to breathe with. An APS Energy Auditor or SRP Energy Auditor will calculate theacceptable “breathing rate” of your home and compare that number with the measured “breathing rate” or house leakiness from a blower door test.
Air Conditioning Saver #4 - Install shade screens in the summer and remove them in the winter
Shade screens help reduce air conditioning costs by blocking up to 90% of the sun’s conductive heat through the windows. Windows account for more than half of the heat gain into your home just because they are transparent and have almost no insulation value. If you do replace yourhome’s windows, gas filled, vinyl windows are the way to go.
Shade screens are typically clipped onto the frame and can be removed during Phoenix’s winter season when we use our heat to get maximum sun exposure to save on heating costs. APS and SRP also give rebates for shade screens if you don’t already have them.
Air Conditioning Saver #5 - Go up to R-38 insulation in your attic
Is it a big surprise that Phoenix attics can get hot in the summer? That huge temperature difference between the attic and the house is another cause of rising air conditioning costs. Against popular thought though, the notion that the quantity of insulation is more important than the quality is completely wrong. It is more important how the insulation was installed than how much you have and a home energy auditor will be able to properly assess your home and tell you how much higher your air conditioning bills are than they should be.
Air Conditioning Saver #6 - Check if there is a direct connection from your garage to the house.
This is not a commonly talked about cause of high air conditioning costs but I have found this problem in houses in Glendale, Scottsdale and Gilbert. The garage is another area that can get very hot in the summer and like I said before, temperature differences are the main driver of heat gain into homes. Using a blower door, your energy auditor will be able to test the house-to-garage connection that occurs above the drywall where you cannot see and estimate the heating and cooling loss occurring from the problem.
Air Conditioning Saver #7 - Have your air conditioning unit tuned-up annual by a trusted HVAC contractor.
I personally know that finding a reliable HVAC contractor can be difficult. Even though you have a friend in the air conditioning business does not mean they will do a good job. I have been in too many homes where an AC contractor and friend installed a new unit and probably not purposely, but unfortunately cut way to many corners simply because that’s the way it’s been done for the last 20 years. After that is done, fixing any of their work is 10 times more difficult. First, the homeowner doesn’t want to point fingers at their buddy’s work, second the homeowner probably doesn’t know what “correct” looks like. Like a good handyman, every homeowner should have a good HVAC contractor.
Those are the 7 ways you can reduce your air conditioning costs dramatically. For others ways to save money on your utility bills be sure to check out our past articles and get up to speed on APS energy audits and SRP energy audits for your home.
If you have had an APS energy audit or SRP energy audit performed on your home the auditor probably showed you the blower door readings or thermal images of your canned lights.These are notoriously leaky and if a smoke pen is held up to the light, you can see the smoke gets easily sucked right up into the attic through recessed light.If your home has more than 10 of these recessed lights, it can be a significant source of air leakage in your home.The average home wastes about $5 to $30 per year per recessed light so it is an important cost savings consideration and health and safety concern if moisture escapes into the attic as well. Here is a little background on these lights and what you can do to stop excess air leakage in your home.
Recessed lights are typically installed in areas of high traffic areas like kitchens, hallways and family rooms.Canned lights are either IC rated, insulation contact rated, or non IC rated, which cannot come into contact with insulation.If additional insulation has ever been added to your home you may want to check that the insulation contractors put some sort of protector around the light before blowing more in.Typically in homes built before 1995, non IC canned lights were used but I have seen plenty of newer homes with non IC rated canned lights installed.You can find out if your lights are IC rated by going in the attic and looking at the nameplate of the metal light.There is usually a label glued on top of the light that says the specifications of the light and it will say, “IC Rated”.
Recessed lights in a two story home can also contribute to the stack effect if there are enough lights in the ceiling.The stack effect is when warm air rises and is replaced by cool air entering the home through outside penetrations and duct leakage.The stack effect and air leakage can be stopped by air sealing the home including the canned lights.To find more information on how canned lights can contribute to the stack effect in your home check out this article by the Pennsylvania Housing Research Center.
There are several ways you can effectively seal your canned lights by either replacement or retrofit.Replacement options can be done with air tight LED lights or air tight recessed canned lights.Both replacements are very effective, the advantages of LEDs are a longer lifespan, are fully dimmable, and use less energy.Replacements done with air tight recessed lights are also very good.I recently performed an energy audit on a home built in 2006 that had the new air tight recessed lights and can verify that the leakage of the light is very low.The reading from the canned light you see on my manometer is 0.9 Pa and a typical canned light measures at 40 Pa, which is a lot of leakage.
The other option is to build energy lids with at least 3-inches of clearance between the light and the box.The energy lid can be fitted over the canned light and sealed at its edges.Warning! Do not use expanding foam to seal a canned light; the foam can drip down into the house and on the trim.The energy lids can be effective if you have non IC rated recessed lights and need to add more insulation to your attic.You can view more tips on how reduce your energy bills here.
SRP has come out with great rebate programs and solidified their commitment to 1) energy retrofits upgrades like duct sealing and insulation, 2) renewable energy products like solar panels for electricity and hot water and finally for 3) switching out old appliances. Each of these rebate programs are separate entities that sometimes get confused since they are always changing. For example, SRP solar rebate program has seen better days when solar electricity rebates used to be at $3.00 per watt. Every couple of months for the last 2 years SRP has dropped their solar rebates until the current amount of $1.45 per watt. Now the best and most affordable way to get solar is through a solar lease program that significantly buys down the costs of solar panels.
SRP Home Energy Audit Rebates
Now the hot program is SRP’s and APS’s Home Performance With Energy Star. This is a national Energy Star program to make homes more healthy, comfortable and efficient. APS and SRP adopted the program to ensure a whole-home approach to reducing energy bills while keeping homeowners safe and with better indoor air quality. SRP requires a $99 energy audit be performed on a home to diagnose the causes of high energy bills, uncomfortable rooms or excessive dust. Once the audit is complete a report will be generated using building modeling software that gives cost savings for each upgrade. The SRP rebates will help pay up to $925 (or more if you have two or more AC units) off the costs of the energy retrofit. The rebates for the Home Performance With Energy Star program are broken down below.
Duct sealing 75% off up to $175 per unit. For most homeowners, 20% of their heating and cooling bill is wasted from duct leakage.
Air sealing 75% off up to $250. Air sealing work can be complex as your auditor must determine
Insulation75% off up to $250
Shade screens $0.80 per sq ft up to $250
SRP has a great visual summary of their rebate program here.
$200 for variable speed pool pump. Each pump has to be calibrated to your pool to ensure that it is not over turning your pool. This upgrade will reduce your bills $200 - $350 per year. SRP also provides a $75 rebate for pool timers. For more information on SRP Pool Pump and Timer Rebate see the following link.
Air conditioning systems have become more efficient from federal standards and better technologies. Surprisingly, SRP does not overlap its duct sealing rebates with its air conditioning rebates. With every unit we install, we include a whole home duct seal to maximize the high efficiency AC unit with a properly sealed duct system, otherwise it’s like using an umbrella with holes in it. SRP will help you pay for a higher efficiency AC unit depending on the efficiency ratings. In the AC efficiency world there is a SEER rating, the seasonal energy efficiency ratio, EER rating, the energy efficiency ratio, and HPSF or . In Phoenix, the EER is a more important number to pay attention to because of how hot it gets here. The EER ratio gives a better idea of how an AC will perform under very hot conditions (100 degrees) were the SEER rating gives an idea of performance under milder conditions (89 degrees). SRP recognizes and awards a higher rebate with higher EERs in their AC rebate program.
SRP also has a quality installation standard similar to the post test done for the home energy audits that has to be met when installing heat pumps and furnaces in the Phoenix area also. Only SRP qualified AC companies can apply for their rebate for you, but not all of them will perform a duct testing and sealing upgrade. These rebates and companies are separate from the solar rebates and the home energy audit rebates. All the SRP approved AC companies are required to do a sizing calculation called the Manual J calculation. You should ask to see the results from your own home to ensure this was done. The AC rebate program also includes a check of the refrigerant charge to make sure that the unit is properly charged to manufacture specifications and a check of the air flow. Below is a list of the AC rebates available from SRP.
SEER 15 with EER 12.0 receives $200 SRP rebate
SEER 16 with EER 12.0 receives $300 SRP rebate
SEER 17 with EER of 12.0 receives $400 SRP rebate
All units must be installed by and SRP approved AC contractor.
All contractors must perform a Manual J calculation to properly size the unit (you should verify this since it is not something a typical contractor will do).
All contractors should properly charge the unit and check airflow.
For more information on SRP AC rebates, check out their link here.
SRP solar rebates are divided into solar electricity rebates and solar hot water rebates. Solar electricity for my home was my dream growing up and has proven to be an attractive idea to thousands of homeowners across the Phoenix valley. SRP perhaps did not realize how attractive solar electricity would be since they have lowered their rebate amount dramatically since its inception. As of September 2011, SRP solar electricity rebate is at $1.35 per watt. You can view their current budget and remaining monies available at the link below.
After City and County applications have been approved, SRP does random inspections of the installation. The solar hot water system must be SRCC rated and have proof onsite. The first 5 feet of your hot and cold water piping should be insulated to at least R-2.6. The panels must be un-shaded during the day for the entire year. The SRP solar water heater rebates are currently at $0.45 per kWh of estimated first year savings (based on the OG-300 ratings), up to 505 off the system’s cost. The OG-300 rating system is based on the manufacturer’s rating by the Solar Rating and Certification Corporation. Also important to consider for solar hot water systems is the federal tax credit of 30% off the cost and Arizona state tax credit of $1,000, which makes solar hot water much more attractive. Typical solar hot water rating systems are around 2,890 kWh per year. An example rebate table is shown below.
So you are doing your due diligence by researching whether or not radiant barrier is a scam is true.Radiant barriers installed in existing homes have generated a lot of confusion and controversy.Often energy saving claims have become grossly bloated from 20% of air conditioning bills to 20% of your entire electricity bill, which is quite different.Consider this, if heat gain into a home with good insulation is only 15%, how can a radiant barrier reduce the energy bill by a minimum of 25%?It’s impossible!
A homeowner today should also be aware that there is no one energy saving upgrade that will create a high performing home in terms of comfort, lower air conditioning bills and air quality.Homeowners should therefore be considerate of alternative recommendations such as duct sealing and air conditioning tune-ups to work in conjunction with a radiant barrier.The Department of Energy has performed studies and written articles on radiant barrier foil and has concluded it works by reducing attic temperatures and thus reduces heat gain into a home.What is the problem then?We will cover that later but first I’d like to go over the different types of radiant barriers on the market.
Radiant barrier paint, radiant barrier chips and radiant barrier foil are the three types of radiant barriers.We do not support the installation of radiant barrier chips or radiant barrier paint.Radiant barrier paint can be diluted in the field with water and will lose its effectiveness when applied.I’ve seen many houses where the radiant paint looks more like gray paint rather than a reflective paint, which is a sign of dilution.Radiant barrier paints also has lower performance standards with higher emittance values and lower reflectance values than traditional radiant barrier foils.Radiant barrier chips are not recommended because installers usually do not install them with enough density to cover the entire surface area of the attic and they can be easily moved.Besides the radiant barrier paint and chips, we do support the use of radiant barrier foils.
The radiant barrier foil comes either in single or double sided; breathable with ventilation holes or it may not have any ventilation; or has a foam core with some insulation value to it.By itself, a radiant barrier has no insulation value because it reflects radiant heat from radiation, unlike insulation that slows down the transfer of heat through conduction.Radiant barriers should also be installed along the roof trusses whenever possible compared to laying along the attic floor.
How Much Heat Comes From The Attic?
Surprisingly, not as much as you would think.According to APS and SRP studies only 14% - 20% of your utility bill is driven by heat gain from the attic, most of it comes from windows.I can also validate these findings from my personal experience modeling hundreds of homes in the Phoenix area under the APS energy audit program and SRP energy auditprogram.On a side note, there is up to $1,000 in APS rebates and SRP rebates available for home energy upgrades.Visit the APS Energy Audit Program and SRP EnergyAudit Program for more information.
If There Is No Radiant Barrier Scam, Then Why Do Most Fail?
The problem just like a driving a Prius with a hole in the gas tank - is how it is installed and a lack of understanding of what homes it will have an effect on and what homes it will do nothing for.Most radiant barriers are sold by a sales consultant who is not a certified energy consultant and will sell radiant barriers to every home they go to and overpromise on their performance.A comprehensive energy audit should be performed with a blower door test and by a BPI Certified auditor to test and identify the real causes and solutions to reduce energy bills and eliminate hot and cold rooms.In an attic with R-38 insulation, the heat gain into the house is small and is approximately 80% conduction and 20% radiation.The radiant barrier is going after that 20% of heat gain which may not be the most cost effective option.There are certain cases where a radiant barrier would be a good choice for your home, but GreenID will not sell or install radiant barriers where it is not needed or better options exist.
Many homeowners have been turning to APS and SRP home energy audits as an alternative to calling their local Air Conditioning Company to diagnose issues such as hot uncomfortable rooms and high energy bills.As part of the APS and SRP energy audit program, 10 CFL light bulbs are given along with low flow aerators to start saving energy immediately.
When CFL bulbs first came out there was some scare about absorbing the metal in our skin and the difference between the mercury vaporizing and aerosolizing.I bet you remember the warnings to never use a vacuum cleaner, broom or pour mercury down the drain.This is because the mercury will aerosolize in a vacuum cleaner, similar to small water droplets in the air from a hot shower, and become smaller droplets with a much bigger radius of influence than if just left as is.If you never use a vacuum cleaner the risk of the metal aerosolizing is zero.
Mercury vaporizing is another way for it to get in the air and potentially cause much more harm.This risk is negated however, because the vaporization point of mercury only occurs at 674 degrees Fahrenheit!Since it never gets that hot (even in July in Phoenix, AZ), you don’t have to worry about mercury vaporizing and inhaling the metal.The main risk of mercury absorption is when a CFL bulb is first dropped and the metal potentially splashes up and hits us.
Here are the EPA’s cleanup instructions in case you do have a mercury spill.
1.Use rubber, nitrile or latex gloves
2.Pick up broken glass with a paper towel and place both items in a labeled zip lock bag
3.Locate visible mercury beads. Use a squeegee or cardboard to gather mercury beads. Use slow sweeping motions to keep mercury from becoming uncontrollable. Take a flashlight, hold it at a low angle close to the floor in a darkened room and look for additional glistening beads of mercury that may be sticking to the surface or in small cracked areas of the surface. Note: Mercury can move surprising distances on hard-flat surfaces, so be sure to inspect the entire room when "searching."
4.Use the eyedropper to collect or draw up the mercury beads. Slowly and carefully squeeze mercury onto a damp paper towel. Place the paper towel in a zip lock bag and secure. Make sure to label the bag as directed by your local health or fire department.
5.After you remove larger beads, put shaving cream on top of small paint brush and gently "dot" the affected area to pick up smaller hard-to-see beads. Alternatively, use duct tape to collect smaller hard-to-see beads. Place the paint brush or duct tape in a zip lock bag and secure. Make sure to label the bag as directed by your local health or fire department.
6.Place all mercury beads and objects into the trash bag. Secure trash bag and label it as directed by your local health or fire department.
7.Contact your local health department, municipal waste authority or your local fire department for proper disposal in accordance with local, state and federal laws.
8.Remember to keep the area well ventilated to the outside (i.e., windows open and fans in exterior windows running) for at least 24 hours after your successful cleanup. Continue to keep pets and children out of cleanup area. If sickness occurs, seek medical attention immediately.
