How much should your home breathe?
The homeowner of this 1930 home in Virginia Highland wanted to know how much her home should “breathe.”
Blower door measuring air leakage
Yes, homes breathe too! In its Home Sealing Specifications, Energy Star recommends to air seal a home to between 0.35 and 0.50 Natural Air Changes per Hour (ACHn). That means that with exterior doors and windows firmly shut, a home should refresh 35% to 50% of the its air per hour, or all its air once every every two to three hours.
Sealing duct registers
Retrofit America’s blower door test during the energy audit measured 0.68 ACHn, showing that the home refreshed its air once every hour-and-a-half. In effect, the HVAC equipment was working overtime so the homeowner was spending good money to heat or cool the outdoors.
Air sealing is a key improvement to most home retrofits. The Energy Star diagram below shows sources of common household air leaks. For this home retrofit, Retrofit America implemented a number of air sealing improvements:
Sealing chimney flue
1. In the attic, we sheathed knee walls, sealed open chases over her bathroom and kitchen cabinet, replaced old recessed lights with modern air-tight fixtures, and sealed two attic hatches.
2. In the basement, we sealed all plumbing penetrations through the subfloor and weather-stripped the basement door.
3. We sealed all ductwork connections to boots and plenums, eliminating leakage of airflow into her attic and basement.
4. Inside the conditioned space, we sealed her chimney flue, caulked around her kitchen cabinets, and weather stripped her front door.
Caulking kitchen cabinets
The Retrofit America crew ran the blower door test as they were air sealing to measure their progress. The final result: 0.44 ACHn, right in the middle of the target range!
Weather-sripping front door
Now this home refreshes its air just over once every two hours – a 35% improvement – reducing the stress on her HVAC equipment, and saving the homeowner money on utility bills!
Retired US veteran and wife get the home comfort they deserve!
John Dorso served 23 years in the US Navy, where he retired as a full Lieutenant. When John and his wife Mary moved into their Roswell home to be near their daughter and grandchildren, they were looking forward to spending their retirement years in a perfectly comfortable home. After a career of service to America, they certainly deserve it!
Upper attic pre-retrofit
But that’s not what they found. “We were uncomfortable with the heating system when we moved in. It was hot upstairs and cold downstairs,” John said. In fact, their utility bills show that they were using a high level of energy at a rate of 14.1 BTU per square foot per degree-day to heat their home. That’s nearly three times as much energy as a home’s optimal efficiency target of 5.0.
Upper attic post-retrofit
Retrofit America made things right for the Dorsos. In winter they were loosing hot air through gaps in insulation in the attic area above. In summer, they could expect heat to radiate into their home through a large attic space that runs over and alongside their second-floor rooms. Retrofit America sprayed open-cell foam insulation along the entire expanse of the attic roof deck and gable walls.
Side attic with spray foam
“The result was incredible in summer,” John says. “We could walk into the attic space, and it would be perfectly comfortable there!”
The Dorsos’ metal duct system was also leaking profusely. Retrofit America applied an Aeroseal process that seals the ducts by pressurizing them and blowing a polymer through the interiors. This reduced the duct leakage from the equivalent of a 54 square inch hole to a one square inch opening!
What’s the overall result for the Dorsos? In the summer, their home’s energy usage for cooling was very efficient at 5.7 BTU/SqFt-DD, and so far this winter they’ve been at 9.8 BTU/SqFt-DD, a 30% savings from their pre-retrofit energy usage for heating.
Sometimes home builders just don’t get insulation right
Jesse and Kathleen Liebman felt that things were not quite right in their Smyrna town house. “The living room was just cold,” says Kathleen. “I knew there were a wide variety of temperatures in the house,” says Jesse, “and I was skeptical that the house was not as tight as it should be.
Unfinished room pre-retrofit
Sometimes home builders just don’t get insulation right. An unfinished room in the Liebman’s third floor had batt insulation on the ceiling but no dry wall. Without the insulation being flush against a hard surface, it was doing no good at all. With no insulation separating the room from the third floor living space or in the floor cavity below, it was a zone to transfer hot air in winter and radiant heat in summer between the attic and the home’s living space. In addition, a supply duct into the room was heating and cooling the attic space.
Unfinished room post-retrofit with interior wall insulation and sheathing
Rather than finishing the room with dry wall to separate it from the attic, the Liebmans chose the less costly option of having Retrofit America insulate the interior walls and floor cavity to separate the room from the conditioned space, and then capping the supply duct.
Crawlspace insulation pre-retrofit
The crawlspace insulation was also installed ineffectively. Fiberglass batt insulation was wedged between I-beams along the entire ceiling, but about 6 inches below the subfloor. Again, with no contact against a hard surface, the insulation was doing no good at all. Retrofit America reinstalled the fiberglass batts, fixing them against the subfloor.
Crawlpace insulation post-retrofit - flush against ceiling
Retrofit America also deployed a specialized crew to reduce the home’s air leakage: sealing ductwork, weather-stripping doors and sealing window sashes and air cavities. The result was to reduce air leakage by 38% as measured by a blower door test, bringing the home’s natural air turns down from once every 1.4 hours to every 2.3 hours – right in the target zone of two to three hours.
“I was surprised how much expertise it took to achieve that full reduction,” Jesse says. “It was a job well done.”
Feel the Difference Living in a Retrofitted Home
- The Bradshaw’s 1908 Home
Bo and Cathy Bradshaw have lived in their 1908 Inman Park home for more than
30 years and felt they knew everything about it. But an energy audit by Retrofit
America taught them a few things they didn’t know.
The heating and cooling ducts were leaking air equivalent to a 48-sq-inch hole.
No insulation in their basement, poor attic insulation with no air sealing and a 20-
year-old water heater were also contributing to high electric bills and the feeling
of a drafty home. Upgrades by Retrofit America could
save the Bradshaws nearly 45 percent on their energy usage for heating and
cooling.
Bradshaw says he had “no idea at all” that his house was that inefficient. “I knew
about retrofitting, and figured I would have to do it eventually,” said Bradshaw.
Armed with the energy audit data and a computerized analysis of their energy
bills, Retrofit America presented the Bradshaws with recommendations on how
to bring their home up to 21st century standards. Company representatives also
helped handle the application process for over three thousands dollars in rebates
from Georgia Power and the city of Atlanta.
Contractors completed most of the work in just three days, and the couple
instantly noticed an improved feel to their home.
“I work in my basement and the noise level has reduced a lot, something my wife
is happy about,” said Bradshaw, concluding that retrofitting is “something that
everyone needs to agree to someday.” It saves money, saves energy, makes a
home more snug. The rejuvenation also improves a homes’ resale value.
Bo and Cathy lead by example in helping to preserve their beloved home and
historic neighborhood. When Retrofit America came to their door, it was an
opportunity they couldn’t pass up.
Barkers improve cooling efficiency by over 3 times!
When Chris and Winnie Barker visited Retrofit America’s booth at the Atlanta Home Show last October, they were looking for a way to bring down their utility bills and make their home more comfortable in Atlanta’s hot summers.
We analyzed their utility bills and found that, in fact, their cooling efficiency was very low. A poorly insulated attic and an uninsulated second-floor crawl space was allowing radiant heat into their living space. Their ductwork was leaking at the boots and plenums and their 1986 AC unit was outdated and inefficient.
Thermal image of air leakage through attic hatch
To retrofit the Barker’s home, Retrofit America increased the blown insulation in their attic to R-38 and installed an insulated tent over their attic access hatch. We installed R-19 fiberglass batt insulation around their crawl space walls and sealed their ductwork with mastic. We also replaced their old AC unit with a SEER 13 system – and we awaited the onset of the summer heat to see our results…
Uninsulated crawl space wall
Summer 2011 was even hotter than the previous two summers, and the Barkers’ cooling efficiency improved by more than three times to meet the challenge – improving from 16.5 to 5.0 BTU per square foot per cooling degree day. (That’s a measure of how much energy it takes to cool one square foot of a home by one degree Fahrenheit over 24 hours.) The chart below shows their monthly kilowatt-hour consumption, pre-retrofit (in blue) and post-retrofit (in green):
The Barkers' cooling efficiency improved by over three times
Chris Barker says: “Meeting Retrofit America at the Atlanta Home show was one of the best things that could have happened to us. The recommended energy saving improvements have made the house environment so much nicer in which to live. Combining the energy rebates from Georgia Power with the noticeable savings on our energy bills is going to give us the return on our investment in less than an year. Thanks Retrofit America!”
FHA loan allows for energy-efficient updates to older home
Thursday, March 17, 2011
By Lori Johnston
For the Atlanta Journal-Constitution
If the idea of buying a home is overwhelming, not to mention the cost and time needed to make energy-efficient updates to an older one, here’s how one recent Atlanta buyer chose a loan to cover the cost of improvements.
For her new home In Grant Park, first-time buyer Leah Carroll worked hard to get an FHA Energy Efficient Mortgage that enabled her to make $13,500 in improvements.
The buyer:Leah Carroll, 31, who works for Fulton County Schools where she tests children for developmental delays.
The challenge: For her first home purchase, Carroll found a two-bedroom, one-bath home in Grant Park, dating to 1935, but wanted the efficiency of a newer home.
The solution: Her agent, Virginia Moran with Keller Williams Realty Atlanta-Perimeter, suggested that she pursue an FHA Energy Efficient Mortgage.
How she did it: Carroll said an important step was to immediately connect with a company qualified to make the changes. Retrofit America arrived one day after her home inspection, providing a home energy audit and assistance as she pursued financing.
http://www.ajchomefinder.com/AJCHomefinder-sharing_/fha-loan-allows-for-875962.html
See the print version from Sunday, March 27
Home Energy Audits: Doctor’s Checkups for a House
Energy audits a recommended first step to improve home’s efficiency, comfort
BY SUSAN ZEVON FOR THE ASSOCIATED PRESS
August 3, 2010 (AP)
Jim Alexander, a real estate agent in Atlanta, decided this summer to subject his own 11-year-old house to an energy audit.
“If this was something I was going to recommend to my clients I wanted to see for myself how it works,” he says. His verdict: “Home energy audits are going to change the way we buy and sell houses in America.”
Alexander hired the company Retrofit America to conduct the audit, which showed that by spending about $3,000 — $700 of it covered by government rebates — he could save several hundred dollars a month in energy costs.
Our Home Energy Audit
From GreentotheScene.com
Checking Furnace
Yesterday Retrofit America came to our house and did a home energy audit. Below are my notes about some of the procedures included and their preliminary findings. The initial estimates say they can reduce my energy bills (gas & electric) by 1/3. Here are some bullet points of how it went down:
Preparing for the energy audit was really easy. All we needed to do was supply them with 12 months of our gas and electric bills. We don’t keep 12 months of bills on hand, so I logged into each account and was able to print them out straight from their website. You can also speak with a rep on the phone and they can typically email or fax the bills to you.
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Duct Blaster
- First thing he did was check the gas lines for leakage, those were all clear
- The water heater is pulling oxygen like it should
- Checked the furnace for carbon monoxide levels >should be below 25 parts per million (ppm), ours are 28ppm > recommends servicing the unit
- There are two chases running from the basement all the way up through the attic which is likely a great source of air leakage…the blower door later confirmed this.
- Insulation in the attic is on average 5 inches. Recommend beefing this up.
- Attic fan is not working therefore not creating any airflow. Recommend adding a ridge vent or spray foam insulation.
- Should also add insulation to the floors where unconditioned space is below.
- Add sheathing to basement walls where unconditioned space is on other side.
- Tip for finding leaks in your house: Look for cobwebs, they typically represent an air leakage (spiders find the fresh air).
- Blower door test revealed .48 air changes per hour.
- .35 is the lowest you can bring it down without adding mechanical features such as fresh air intake…would ultimately strive to be zero air changes.
- Tons of air loss at attic door and basement doors to unconditioned space and garage
- Windows actually looked pretty good because of strip caulk done at cracks
- Duct blaster revealed 25% air leakage
- Most of the leakage seemed to be at the supply vents. They need to be sealed and insulated.
- Suggested adding a low-e film to front windows to reduce radiant heat gain in summer.
Here is a slideshow showing what was done and some of the areas that need improving on:
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