The Green Dream Group Blog

Let me start by making sure we’re clear on one point: electricity doesn’t factor into our home energy audits.  The reason for that is that electricity use in homes is much more straightforward to deal with (in areas that use don’t use electric heat) than the whole-building issues Green Dream Group focuses on.  Also, in this climate, the savings you can expect to see from switching out light bulbs, or even switching to more efficient appliances, aren’t generally as impressive as the ones you could realize from air sealing and insulating your home.  So this post has little to do with energy audits, but my hope is that it’ll be a helpful resource for people interested in saving as much energy (and money) as possible, rather than focusing only on the big projects.

Home Energy Use by Cost

To begin with, let’s take a look at how energy use in the average home breaks down by cost.  The Energy Information Administration (EIA) numbers show space heating (and cooling) together making up around 43% of your energy bill, with water heating as another 12%.  Appliances and lighting use around 37% of your energy bill.  The remaining 8% varies from home to home.  Bear in mind that if your average yearly costs are very different from these averages, you’ll be able to save more on whatever portion of your bill is larger.  More information is available at: http://www1.eere.energy.gov/consumer/tips/home_energy.html

So what are the best ways to save on electricity use in your home?  There are a couple of ways to answer that.  The most straightforward answer is to minimize your use of anything that requires electricity - refrigerators, computers, A/C, lighting, plug-in hybrid cars, you name it.  That could mean getting rid of a second refrigerator, making sure to always turn appliances off - or better, unplug them - or turning off lights when you’re not in a room.  You could go all out with this strategy; for example, I’d like to stop using the refrigerator entirely.  A couple years ago, I lived for 6 months without a fridge - drinking soy milk instead of cow’s milk, making no more than weekly trips to the grocery store, eating almost no meat - and it was surprisingly easy to pull off.  But I haven’t convinced my current roommates that it would be worth it yet… which may have something to do with our shared love of ice cream. 

There are also a variety of ways to reduce your energy use without going all-out down the conservation road.  These tend to get the most press, because they allow you to maintain the same lifestyle and still reduce your energy usage.  Two of the most popular of these solutions are switching to compact fluorescents (CFLs) and using power strips to turn off appliances when they’re not in use.  CFLs use 1/5 as much energy as incandescent bulbs to produce the same amount of light (measured in lumens), so if you used CFLs exclusively, you could cut your total energy use by as much as 9%.*  Power strips are good for those energy suckers that use energy even when they’re turned off - up to 10% of the amount you spend on electricity could be going to those greedy machines.  You don’t need a power strip to turn off your appliances, of course, but it is nice to only have a couple of switches to worry about, instead of a whole houseful of electronics.

One problem with all of this is that using less energy over the long run so often requires buying something new - light bulbs, appliances, one of those kill-a-watt meters that helps you measure energy flow to a device.  I haven’t found a lifecycle analysis yet for CFLs that includes the impact of manufacturing & transporting them all over the world, let alone the additional cost of returning them to manufacturers for safe disposal, or the comparison of those costs to the ones incurred by reasonable alternatives.

The approach I like to take to saving electricity at home is a comfortable blend of conservation (laundry once every 3 weeks, low temperature settings on the furnace & water heater) with convenience (CFLs & power strips).  The best way to find out what you’re comfortable with is just to take the plunge, and try out a few different options.  Who knows - maybe getting rid of the fridge will be part of the lifestyle change that makes you happier & more fulfilled.  And if, like my household, you just can’t imagine a house without ice cream, remember that there are plenty of other ways to get your ice cream fix than keeping it in the fridge for days.  And there are plenty of other ways to save energy, too!

If you’ve got a favorite strategy or action that helps household energy conservation, I’d love to hear about it!   Drop me a comment, and I’ll get back to you as soon as I can.  And enjoy your experiments in saving energy!

*Though it’s most effective to install CFLs in high-use areas, like living rooms, rather than closets or hallways.  Their lifespan is limited mostly by how often they’re turned on & off, so it’s more cost-effective in the long term to use them where they’ll be on for more than 5-10 minutes at a stretch.

I thought it would be fun to go through some of the more piecemeal strategies for insulating and air-sealing homes this time around.  You know, the Do-It-Yourself type strategies.  The kind of upgrades that are even worthwhile for me, in my rental house.  If I miss something you’ve done, especially if you’ve seen good results, I’d love to hear about it!

The To-Do List.

To begin with, I should let you know that my current rental was built back in the 1870s.  I have no idea what kind of insulation, if any, is in the walls.  Sticking my head up into the attic was one of the most frightening things I’ve ever done - the insulation was black and stringy, and the way it was hanging from the rafters made it look like snakes, or bats - and I could feel dust seeping into my lungs every second I tried to look around.  There are a couple of rooms that never seem to get warmer than 55 in the winter, even when the thermostat is set to 67. 

Basically, this house has more than its share of challenges… and we’re paying for heat.  We haven’t taken a close enough look at how our heating bills compare to heating degree days (HDD), so I can’t tell you with any confidence that some particular combination of strategies saved me so much on my gas bills.  I wish I could.  I’m definitely more comfortable in my bedroom now, where the window over the bed has caulk around the edges and is covered in plastic.  But hard evidence aside, if you’re interested in spending a little less on gas, or just feeling more comfortable in your home, these suggestions will help.  Here’s a short list of DIY upgrades that should save you money on heating in the short run.  We’ve got some great videos on the main page illustrating precisely how to install these upgrades the right way: www.GreenDreamGroup.com/resources/diyvideo

Some serious AC action

- take room A/C units out of the windows in winter - leaving them in is like leaving a window open all winter, which doesn’t make much sense.  If your A/C is permanently installed, do your best to cover it up, inside and out, with plastic and/or insulating blankets, rigid foamboard, or anything to slow air escaping.  This is a huge source of heat loss!

- weatherstrip around doors & locking windows; if there’s no lock, you won’t be able to keep the window pressed against the weatherstripping firmly enough to reap any benefits.

- caulk or sprayfoam around visible holes - door frames, windows, dryer vents, electrical or plumbing penetrations.  (Finding these holes can be a fun activity to tackle with your kids.)

- cover the windows with plastic: most effective if you have single-paned windows, like I do.  With double- or triple-paned windows, most of the leakage tends to occur around the edge of the framing, so plastic won’t be as effective.

- caulk behind baseboards - they’re often covering up the seams of a house, which is exactly where air tends to leak in. 

- Finally, one thing NOT to do: if you have a gas oven with an exhaust fan over it, DO NOT stuff insulation into the fan and cover it with plastic!  The reason the exhaust fan  is there is because the fumes from your oven could be dangerous to have in your breathing space.  Even having a carbon monoxide detector in the same room isn’t the same as standing over the oven for a couple of hours - the concentration of CO is much higher closer to the source.  If you feel cold air coming in when the fan’s not in use, try checking the outside of the house - make sure the flap on the other end of the exhaust vent closes snugly, or install a new one.

Now that winter this year is almost over, it may not make sense to complete everything on that list.  Some of the upgrades last a long time, and some need to be replaced every year, like window plastic.  Use your best judgment, check our online videos for tips, and let us know any other ideas you’ve heard or are using.  And have fun! 

Evidence of ice damming

Ice dams are a great example of a common problem in home performance, which boils down to a lack of understanding of building science.  If you think that ice dams happen because your roof was installed poorly, or because of ice-filled gutters, it makes sense to replace gutters or re-do a roof.  And there are a lot of temporary solutions for ice dams floating around out there, from removing gutters to using a roof rake to dislodge ice to creative ways to melt the ice or remove the snow from your roof.  Unfortunately, none of these fixes actually addresses the reasons that ice dams form - they’re about as useful as band-aids on a severed limb.

In the simplest terms, ice dams happen when your roof is unevenly heated.  For ice dams to occur, snow must be present on the roof, part of the roof must be below freezing, and part must be above freezing.  The snow melts where the roof is above freezing, runs down to where the roof is below freezing, and freezes.  Continued melting and freezing can cause water to pool in the gutters or behind an ice dam anywhere on the roof.  Eventually, those pools can penetrate the building envelope, and show up as leaks on your walls or ceilings. 

Stop that heat escaping!

There’s one real solution to ice dams that trumps them all.  It prevents the possibility of more ice dams forming in the future.  It saves energy.  It’s very low-maintenance.  It isn’t even that expensive.  However, it’s also not intuitive, until you understand that ice damming is caused primarily by heat loss through the attic. 

What is that real solution, you ask?  Insulate and air-seal your attic, which prevents the attic from heating up, which prevents the snow on your roof from melting in the first place. 

This isn’t just good building science: it’s good sense.

Part II:  The Attic

Attics are often very confused spaces.  Many attics were built to be outside the building envelope, but over time, inhabitants decided to extend their living space into the attic, to store stuff up there, or simply failed to install a thoroughly weather-stripped and insulated attic hatch.  Remember that since heated air rises, attics are one of the most important areas of your home to address in terms of energy savings.  (Check our Home Improvement Calculator for details!)

During the blower door test, we do zonal pressure testing on every room or area in the house to see how well connected it is to outside.  The hope is that everything inside the house is basically cut off from the outside, which should be reflected by similar pressures during the test.  Numbers range from 0 pascals (inside) to 50 pascals (outisde) - and attics usually register between 25 and 35 pascals.  What these numbers show is that most attic spaces are actually better connected to outside than they are to inside.  Unfortunately, an attic in that range still communicates well enough with your conditioned spaces to allow plenty of heat to escape, which does nothing good for your energy bills.

So, how can you start to clear up this confusion about whether your attic is an indoor or an outdoor space?  For starters, take a trip up there and look around.  Look, in particular, for insulation.  If there’s insulation at the floor level, the attic was intended to be outside.  If insulation is on the rafters, the attic is probably more a part of the conditioned space in your home.

Once you’ve figured out whether the attic was intended to be inside or outside by its builders, look at how you use it (or how you don’t use it).  The key point here is that the way you use your attic should match the way it was built.  For example, if you never go up into the attic at all, but the insulation up there is at ceiling level, you’re heating all that space to no purpose.  On the other hand, if you use your attic as storage and the insulation is at floor level, you should know that whatever you’re storing up there is effectively outside.

Especially important: make sure your attic access is well-sealed and insulated!!  If your attic is insulated to R-38 (per the Chicago code) across 99% of its area, and the attic hatch (1%) is uninsulated, the R-value for the entire assembly drops from R-38 to R-28! Payback on air-sealing and insulating the attic access in that situation would be under a month, especially in our fast-approaching Chicago winter!  If that sounds good to you, head out to Home Depot to get some supplies, hole up with our DIY weatherization videos, or get a contractor from our Affiliate List to help you out.

"All in One"

There’s a kind of obsession these days with devices that let you do everything at once.  All-in-one office machines, phones that have internet access, even one-stop-shopping.  Not that trying to do everything at once is bad - it just doesn’t work out every time.

Furnace filters are one of those times when trying to do everything at once just doesn’t work.  Let’s get one thing perfectly clear, so we can work from common ground: your furnace is NOT an air purifier.  It is a heater.  And misunderstanding or misusing furnace filters are one of the easiest ways for you to make your furnace work less efficiently.

Sample blower from a furnace

Furnace filters are designed to protect your furnace’s blower - a small but powerful fan - from damage by particles in the air.  Clearly, some level of protection is in order, since rocks, leaves. or rodents hanging out with your blower would not be conducive to healthy equipment.  However, in order for the furnace to burn fuel and heat your home, air still needs to slip in through the furnace filter.  When you get a super-fine furnace filter, not only does it keep inconsequentially small particles out of your furnace, it also makes your furnace work a lot harder to achieve the desired result: a warm house for you to come home to. 

IAQ Source put it pretty well in response to the (apparently frequent) query about whether or not HEPA filters can be installed on furnaces.  “Unfortunately, HEPA filters restrict too much air to be used as a traditional furnace filter. A HEPA filter is extremely efficient, but a significant amount of air pressure is needed to force air through a HEPA filter. A typical HVAC system will not be equipped to provide enough air pressure to use a HEPA filter - which basically means that no air would blow out of your registers.”  By efficient, they mean the HEPA filter works well for its intended purpose: filtering tiny particles out of the air for your respiratory comfort, not helping your furnace work more efficiently.

Air Purifier

For once, there’s a simple fix:  If you or someone in your family has allergies, get an air purifier.  For your furnace’s good health, buy a cheap, coarse furnace filter and replace it as directed.  Don’t buy the expensive, super-”efficient” filters; the only sure thing that’ll accomplish is making you replace your entire furnace sooner.  And there’s nothing efficient about that.