Blogs > Tom Miller > February 2010

Insulation: The key to energy efficiency? Absolutely!

Tony Zinger from Wolfe Insulation walked into the house, looked around, and commented that our utility bills were probably pretty high. He was right.
Tony is an insulation industry veteran. In fact he knew all about my mid-century modern home, because over the years he has made dozens of them more energy efficient. I told Tony about the blower door tests and the sealing that was done. He reviewed the report on leakage, examined the infrared photos. They confirmed what he thought: basically there was little to no insulation in the home. A look into the attics confirmed the fact.

Inspecting in the crawl space, Tony noticed that there was minimal insulation in the wall area where the foundation meets the stud walls…in fact you could reach your hand under the exterior siding into the great outdoors!

Photo: It’s not mold, it’s 50 years of air blowing through the insulation

After more than an hour of inspection, measurements and discussion it was time to work up a quote. It included spray foam in the crawl space and all along the perimeter of the stud wall where it meets the foundation. It also included adding fiberglass blow-in insulation and batts in the attic areas. The work was pretty extensive and took three days to complete. They sprayed the foam insulation on a Friday, and we visited friends out of town, because Tony told us that it wouldn’t be a good idea to be in the house for two days while the foam off-gassed. Good advice, because when we came back Sunday evening you could still smell it, but opening the windows for a bit seemed to work.

A few weeks after the work was completed the weather turned pretty cold, and we noticed right away that the home felt cozier. No drafts. In fact, we even turned the thermostat down several degrees and still felt comfortable. Then the gas bills started showing up, and we could see right away that we were using less energy.

And when it snowed several inches, the snow on the roof didn’t melt off right away like it used to. So far, the sealing and insulation seemed like great values compared to the relatively reasonable costs incurred. It will be interesting to continue tracking our energy consumption to see how much less we’re using to heat and cool.

What did I learn? First, find out what the insulation situation is in your attic, walls and crawl space….and then add more. Even when it got down to zero, we stayed very comfortable without having the turn up the thermostat. Second, check around until you find a guy like Tony who is knowledgeable and willing to take the time to explain all of the issues and do it right.

Posted: 2/26/2010 11:38:36 AM by | with 0 comments

Sealing: Time to get to work

Like every other homeowner, I receive the bill stuffers from my utilities every autumn reminding me to “seal up the cracks to save energy.” And in the past, I’d go buy tubes of sealant and walk around the house hunting for energy leaks. And generally, found few.
After the blower door test, however, I knew exactly where the big leaks were, inside and out. My painter, Scott Schmitt of Greenbrush Painters, is not only a great painter but also a green one. He and his crew reviewed the results from the blower door tests and went to work.

They started on the outside, and spent the better part of a day sealing. When I arrived to review the results, I literally couldn’t see where they had sealed until they walked around and pointed out their work. That was the aha! moment. The vast majority of the leaks were coming in from very small gaps around windows, under the eaves, where siding butted up against bandboards and so on.

Building pros probably know all this, but it was a revelation to me. A little sealant in the right place goes a long way. And Scott used a clear sealant that can be painted, so next spring when the outside gets painted, it will be invisible.

The next day was spent sealing indoors. It went a bit faster, about fours hours with two people. Once again, it was amazing where the air was getting into the home. When they finished, you couldn’t see the sealant, and I sensed that the home felt less drafty when the weather turned cold. But now it’s time to tackle the big energy issue: insulation.

Posted: 2/15/2010 2:39:31 PM by | with 0 comments

You mean there’s more to it than just a blower door test?

I was very fortunate to find the most knowledgeable person I have spoken to about how to make my home more efficient and green.

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.

Posted: 2/3/2010 11:33:00 PM by | with 0 comments

About Me

Tom Miller is not a building scientist, green guru or even a halfway decent DIYer. However, he is passionate about making a difference, ecologically speaking.

The purpose of Tom’s blog is to share experiences and observations from a homeowner’s perspective in the hopes that it will help building professionals spot unmet needs and dramatically increase the velocity of green building adoption across the country.




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