The best way to insulate your attic – part 2

Wow, where's that hole go?

In the first installment on attic insulation, I discussed why it can be dangerous to add insulation to your attic without air sealing the attic floor first. Moisture can slip through tiny cracks in the attic floor and lead to rotten roofs. Given this information, we walked through the process of finding and sealing all those insidious air leaks in your attic, some easy, some difficult. But finally, after fixing all these problems, you could lay more insulation down on your attic floor, more confident that doing so wouldn’t lead to a humid, moldy attic.

But what if there’s an easier way?

Whether you’re building a new house or retrofitting an older one, you can make life much easier on yourself by using professionally applied spray foam insulation that air seals and insulates in one shot. There are two ways of doing this, each with their own benefits and disadvantages. We’re going to review both methods. One is spraying foam on the attic floor, instead of using loose fill or batt insulation. The other is spraying foam under the roof deck. Continue reading

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How to prevent your boiler from stealing your money

Energy Kinetics System 2000

Energy Kinetics System 2000

In the last article, “Is your boiler stealing your money?“, I discussed why most boilers are ripping you off. Contrary to what almost every HVAC saleperson or tech will tell you, your boiler does not operate at 84% efficiency. It doesn’t operate at 80%! Heck, much of the year, it doesn’t operate at 50% efficiency!

To review, the reasons for this include:

  • High operating temperature
  • Minimal insulation
  • Infrequent use
  • → Outrageously high standby losses

In this article, I’m going to discuss how to do it right. But if you’re too lazy to read the entire article, stop right here and go to the Energy Kinetics website.

But first, I’m going to save you $10,000….

Continue reading

Is your boiler stealing your money?

Boilers - notorious energy hogs

If you have a boiler, chances are, it’s wasting a lot of energy!

At today’s fuel oil costs, (~$3.50/gallon in March 2011), it’s more important than ever to conserve. This is definitely one of those cases where it pays to do your homework.

What if I told you there’s a good chance that your boiler is half as efficient as they told you? You wouldn’t be happy, would you?

Let me tell you a personal story. When I moved in my house, it had a relatively modern boiler, rated at 82% efficiency. It heated the houe and the water. I figured that was pretty good – no need to upgrade, right?

Continue reading

Energy Geek Video – New CREE CR6 LED Downlight Replacement

The CREE CR6 is the latest in a line of energy efficient LED lights made by CREE. This light addresses some of the issues of the earlier lights, allowing dimming down to 5% and having a compact, light-weight package at about half the cost of earlier models.

It draws only 10.5 Watts yet produces as much light as a 65W incandescent bulb, so it’s definitely an energy saver. That’s a 55 lumen/Watt rating, putting it in the same ballpark as a normal CFL spiral bulb. But the fair comparison is with dimmable fluorescent downlights. Those range from 40 to 50 lm/W, so on average, you get 10%-25% more light from the CREE than you would the equivalent fluorescent.

Continue reading

Pharox Dimmable LED Bulb

Pharox 300 Dimmable LED

Just got a Pharox 300 dimmable LED bulb after my nephew (thanks Jason!) reported success with his. Guess what? It actually works as advertised! The thing dims right along with a conventional incandescent bulb – finally!

This is a standard Edison bulb, so you can use it in just about any fixture. The light is bright white and it stays that way as it dims. I know we’re all used to the dull yellow-orange light from an incandescent as it dims, so seeing a dim white might at first be a little disconcerting but over time, I suspect people will get used to it.

The Pharox is surprisingly bright for a bulb that only uses 6 watts. Remember that the output of LEDs is somewhat directional, so you’ll get the most light if you use this in a desk lamp that points towards your work surface or put it in a light fixture above you that’s pointing down. In this application, it works really well.

The dimmability is really impressive. I’ll have to do a video showing how it dims along with a conventional bulb. I’ve never seen an efficient bulb work this well. Every other one that I’ve used cuts out after it dims just a little bit but this one actually provides useful dimming. Very cool!

I’ve ordered another four to try in more fixtures around the house. At under $30, they may seem expensive (ok, they ARE expensive) but they’re a steal compared to other high quality LED bulbs. And for the energy savings, you’ll pay it back in a year if you put some in the kid’s rooms!

I’ll do more reports about it when I get some longer term tests. But for now, it’s definitely worth a try!

Other Pharox Resources

Pharox website

Inhabit.com review

KK Cool Tools review

LED Insider – review of an older version of the bulb

1 Green Product – News and reviews. One of the longer reviews of the Pharox

Types of Insulation: Part 2 – Where does insulation go?

In part 1 of this series, I gave you an overview of the different insulation materials and the various forms they come in. This article covers where insulation goes and why. Knowing this helps you understand why you’d want to use a particular type of insulation for specific applications in your home.

Where do you use insulation?

  • On the attic floor
  • In attic cavities
  • On an attic knee wall
  • On the attic ceiling
  • In the walls
  • Around the windows and doors
  • Around pipes and other holes in the wall
  • In the basement and crawlspace ceilings
  • On the basement and crawlspace walls
  • Under the slab
  • Outside the foundations

Each of these areas really deserves an article of its own. In fact, if you look on the Building Science website, you’ll find highly detailed articles doing exactly that.  If you want to go straight to the source, consult these references.

Let’s look at some photos to get an idea of several of these cases…

Continue reading

Bright Ideas for Saving Energy #4 – Window Dressing

We’ve all heard the hype – buy new windows and save 35% on your next heating bill. To put it politely, that’s a bunch of hooey. Unless your windows are old, poorly installed, leaky and missing half the glass, you are not going to save 35% on your heating bills. In fact, there are numerous studies showing that replacing windows is among the least cost effective measures for improving your home’s energy efficiency!

That said, windows are among the worst performing parts of your home when it comes to energy efficiency. Did you know that a single, 3 by 5 foot window can double the energy loss for the wall in which it’s mounted? This is why manufacturers often make such outrageous claims about energy savings. But a home loses energy through more places than its walls. It loses energy through air infiltration, walls, windows, doors, ceilings, the foundation and the slab.

Let’s compare a variety of window styles and their relative energy loss. But first, a definition:

U-value: is a measure of the energy transfer through a window. The higher the U-value, the greater the energy transfer and the worse the insulating ability of the window.

  1. Single glazed, clear glass, metal frame. U-value is above 1.0. Metal framed windows are the worst since metal conducts heat so well.
  2. Single glazed, clear glass, non-metal frame. U = 0.71 to 0.99
  3. Double glazed, clear glass, metal frame. U = 0.71 to 0.99. An old wooden, single glazed window is better than a metal framed double glazed window.
  4. Single glazed window with tight storm window. U = 0.50
  5. Double glazed, clear glass. Non-metal frame. U = 0.41 to 0.55
  6. Double glazed, low-e glass. Non-metal frame. U = 0.26 to 0.40 depending upon frame.
  7. Triple glazed, low-e glass. Non-metal frame. U = 0.15 to 0.25

Comparing U-values, we can directly compare the relative energy efficiencies of these different styles of window. For example, if you install a super insulating, triple glazed window with a U-value of 0.20, this will lose 20%-25% as much energy as an old single glazed clear glass window. That is truly substantial. In fact, when I renovated my own home, I went this route. Not because I knew the energy savings will pay off (they won’t) but I was trying to optimize my entire home’s energy efficiency and comfort.

Suppose you have a moderately old wood frame, single glazed window with a tight fitting storm window. This might have a U-value of around 0.50. If you were upgrading to a double-glazed, low-e window, which typically has a U-value of about 0.35, then the new windows would only reduce the energy loss through the window by 30%. Not bad, but not great and probably not worth the investment.

In addition, most new windows are installed poorly. I have seen many instances where a house was less comfortable after installing new windows. Why? Because the installers did not seal around the windows properly and air infiltration is much worse for energy loss than is poor insulation.

If you remove the trim from around a window, you would see something like this. The window unit would be shimmed out and nailed into place. Around the perimeter are big air gaps. Sometimes, you can even see right outdoors.

The problem is, most installers just shove fiberglass in these cracks. Fiberglass is not an air barrier. In fact, when compressed like this, it isn’t even a good insulator!

Please see my website for more detailed information on proper window installation.

For all these reasons, if your windows are in good shape and don’t seem drafty now, then I usually don’t recommend replacing them. Instead, start with some high-quality window treatments.

It’s amazing how much of a difference cellular shades or window quilts can make. At a fraction of the cost and disturbance of new windows, properly installed shades or window quilts can reduce energy loss by anywhere from 50% to 80%, making your home more comfortable and energy efficient.

Practically speaking, usually I recommend that people outfit one room with these initially to see if they yield the desired improvement. However, you really can’t go wrong with these unless you’re planning on renovating anyway and will be upgrading the windows. In that case, I suggest holding off on the window treatments until you get the new windows because often the new windows will be a different size and the treatments might not fit then ew windows.

For more detailed information, please see the links below.

Other links:

Dept. of Energy – Energy Performance ratings for Windows

Dept. of Energy – Energy Saver Tips for Windows

Efficient Windows Collaborative for more technical information on windows.

Florida Solar Energy Center – Windows

Grace-Vycor – Contractor’s Guide to Window Installation

National Fenestration Rating Council – General website