Roger Clearman owns Air And Energy Products in Kennesaw, Georgia. Roger has a delightful way of helping regular consumers like myself understand the basic principles of building science. Roger is really bilingual – he speaks contractor and consumer, a rare talent.
Plus, he helped me understand that when it comes to evaluating the energy efficiency of a home, you need to know more – much more – about not just the exterior walls (the building envelope) but about how it interacts with the HVAC system.
The other great thing that Roger did was introduce me to Ray Dicks, from Atlanta. Ray is with Comfort Systems, and after discussing my situation he said he’d like to give my home a second opinion. And several weeks later he did just that.
Oh my goodness.
Ray showed up with his assistant Chuck, plus a blower door, several computers and a printer, all sorts of hoods and baffles and cameras (regular and infrared), smoke puffers and others items too numerous to mention.
Blower door test
Duct efficiency (leakage) test
For a solid day, Ray and Chuck surveyed and poked into every single area of my home. And the whole time, Ray peppered me with questions like:
+ Is air leaking in from around doors and windows good air or bad air? (Good, as long as there’s not too much of it).
+ Is air leaking from the HVAC ducts good or bad? (Bad).
+ Is air leaking in from your crawl space, or from your attic around the lighting fixtures good or bad? (Very Bad).
+Why does your house feel so clammy in the summer with the air conditioning on? (It’s the humidity).
Air leakage on outside wall
Floor above crawl space air leakage
Recessed light attic air leaks
After eight hours, I was exhausted. Ray was just getting started. The three of us adjourned for dinner, where the education continued. Ray had run all the reports, and while referring to a dozen different ASTM and ASHRE specs, told me where I needed to fix the things that were wrong with my home. The list was almost two pages long.
Here’s what just some of the findings were:
The national ventilation standard for a home my size recommends the air in the home be exchanged with fresh outside air 6.4 times each day. That translates to 1.9 square feet of “air leaks”. One way to think of it is a hole that size in the wall.
My home had 3.3 square feet of air leakage. So instead of exchanging air 6.4 times a day, my home was exchanging air 11.3 times a day, or 1.8 times above the recommended average.
I was losing 15% of my air conditioner capacity and 14% of my heating capacity due to duct leaks. The overall efficiency loss of heating and cooling was 11% on an average day. On the hottest and coldest days, the loss was 21% for air conditioning and 17% for the furnaces.
What did I learn from Ray: That good, solid data can help you make the right investment decisions. I won’t go into all of them right now, but Ray’s recommendations will show up throughout future postings.
Ray brought a holistic perspective to the discussion. Until Roger and Ray, everyone talked about a home from a single perspective, like the three blind people touching a different part of the elephant. These guys put it all together for me. I started to think of my home as a system.
And, Ray supplied the hard data, printed in report form on the spot, so I could get a real feeling for just how my 50-year-old system was doing. Unfortunately, the system was not as impressive as Ray’s analysis. There is work to be done.