Category Archives: Energy Focus Articles

Stock up that refrigerator — it could save you money

Ask a Builder

By Cold Climate Housing Research Center Staff

 Q: I heard a full refrigerator uses less electricity. Is that true?

When it comes to fridges and freezers, always try to keep them full. These appliances measure the temperature in the storage space and adjust to keep that temperature below a certain level. The more empty space, the more energy needed to keep that space cold. Since it is not always possible to keep your refrigerator or freezer full, it helps to fill up old milk jugs with water and put them inside to take up space.

Q: What are my options for putting insulation on the outside of my house?

Locally sold rigid foams work quite well. White foam, which is expanded polystyrene, or EPS, and blue and pink foams, which are extruded polystyrene, or XPS, all work well. Foil-faced foams also work well and have the highest R-value. The foil facing also makes them impermeable to moisture. 

Remember, any time foam is applied to the outside of a home, it will make the home much “tighter” — the building will have fewer cracks and holes.

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Alaska BEES; problems with wood burning

Alaska HomeWise: Ask a Builder

By Cold Climate Housing Research Center Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

I have heard of the BEES regulations in Alaska, though I don’t know quite what they are. Is this something I should know about if I am a homeowner or want to build a home?

The BEES (Building Energy Efficiency Standard) regulations are part of the compliance requirements for any home built to Alaska Housing Finance Corporation’s (AHFC) cold climate construction standards. More recently, AHFC has adopted the International Energy Conservation Code and amended specific portions of it for construction in Alaska. Because we are a colder climate, AHFC has set higher insulation values for windows, floors, roofs, walls, and other areas. There is also an energy credit for building a home that meets AHFC 5 star plus requirements. In addition, a mortgage rate reduction is possible through AHFC when purchasing a four or five-star home that meets current AHFC BEES standards. When considering this credit, make sure to start the paperwork and have a state certified inspector on board before breaking ground. Also, local contractors should be familiar with the AHFC requirements, so ask before you start building.

The BEES regulations can be found on the AHFC website and are arranged by region. For each area of the state, the minimum insulation requirements are listed for windows, walls and other parts of a home. The statewide recommendations for ventilation are also covered. What is important to remember, is that the BEES regulations are minimums and more insulation is still beneficial in many cases.

The current AHFC requirements can be found here: http://www.ahfc.state.ak.us/iceimages/reference/bees_amendments.pdf

A lot of the problems with burning wood have to do with moisture content. Tell me more about that.

The higher the moisture levels in the wood, the more heat energy is going to be required to turn that moisture into water vapor so it can exit the wood and allow it to burn. Essentially, burning wet wood, or fresh-cut “green” wood is wasting energy because the fire is not burning hot enough and creates more combustion byproducts while trying to get rid of moisture. The end result is creosote and ash that can build up in your stove and stovepipe. In addition, because the wood is not burning completely, the smoke it creates has a higher amount of fine particulate material known as PM 2.5, which can be hazardous to health.

To combat moisture, wood must be dried sufficiently. Wood should be split, stacked and covered in the summer months so that it is ready when needed. A woodpile should be protected from precipitation, but the sides should remain exposed to allow the stack to continue drying. A moisture content of 20% or less is ideal. Green birch and aspen can contain up to 80% moisture by weight. The inefficiency of burning anything over 20% moisture leads to progressive increases in creosote and particulates.

If you want the full story on wood-burning in the interior, along with a wealth of information regarding proper burning techniques, the Fairbanks North Star Borough is putting on two open houses on wood burning and PM 2.5 next week. The open houses take place Tuesday, April 13th at the Morris Thompson Cultural and Visitor’s Center and Wednesday, April 14 at the North Pole Middle School cafeteria.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Decoding dust patterns; stovepipe clearance; Fairbanks building codes

Alaska HomeWise: Ask a Builder

By Cold Climate Housing Research Center Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

My walls have black lines where dust has collected. What could cause dust to collect in this pattern?

One telltale sign that you have heat loss through the framing in your house is that the studs will be outlined in black lines on interior walls. This is what happens when moist indoor air condenses on the cooler portions of a wall where the studs are located. Air carries tiny little dirt particles, so as moist air condenses on those studs, the particles accumulate on the wall and begin to show over time.

These black lines are a sign of significant heat loss in a building, but there are steps you can take to reduce this heat loss, including retrofitting your walls or reducing the amount of moisture in your home.

Any suggestions on how much airspace to leave around my stovepipe?

One of the biggest issues associated with houses burning down is that not enough clearance is left around the stovepipe, or insulation is stuffed right up against the pipe. After years of the insulation or wood constantly being exposed to heat, the ignition point of that material drops, and it takes a lot less heat for it to catch on fire. One hot stove fire, or worse a chimney fire, could ignite that material. If you are able to get into the attic, take a look at the pipe and make sure it has the required amount of clearance between the chimney and the insulation or chimney and the rest of the structure. Typically there should be at least two inches of air space around the pipe. If there is any doubt, or if there has ever been a chimney fire, consult a chimney sweep.

Where can people go if they want more information on Fairbanks building code?

The best thing to do is call the City of Fairbanks Building Department or visit them online at www.ci.fairbanks.ak.us/departments/building/building.php. The website has a lot of information regarding the permitting process, local amendments, typical details for foundations, and much more. Remember, building codes vary from city to city and they do change often, so review them, especially the local amendments, in case something has changed.

Also, if you are looking for advanced energy standard information the Alaska Housing Finance Corporation has developed Alaska-Specific Amendments to the International Energy Conservation Code 2006 and American Society of Heating, Refrigerating, and Air-Conditioning Engineers Standard 62.2-2004. These are a great place to start if you want to build an energy efficient home in Alaska. http://www.ahfc.state.ak.us/iceimages/reference/bees_amendments.pdf

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Metal-framed windows in Alaska; problems with heat pumps; woodworking with birch

Alaska HomeWise: Ask a Builder

By Cold Climate Housing Research Center Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

I heard that metal-framed windows are a bad choice for Alaska. Why and what should I do about it?

Most metal-framed windows are made from aluminum which is a highly conductive material. The laws of physics dictate that heat will always move in the direction of cold. When the temperatures drop outside, the aluminum acts as a pipeline, moving heat from inside to outside. Also, a colder window is more sensitive to moisture and will gather condensation.

Replacing metal frames is the preferable thing to do, however, not always practical. Fortunately, there are some other easy solutions. Covering the inside face of a window with a shrink wrap will create dead air space that will help keep the window warmer. Curtains and shutters will help as well.

I am thinking of putting in a heat pump system for my home. What types of problems are associated with heat pumps?

While they are a proven technology in the lower 48 states, heat pumps are still a relatively new technology in the state of Alaska. Heat pump performance can vary significantly with different soil conditions and site exposures. As a result, installations need to be evaluated on an individual basis.

When installing a heat pump system, caution must be taken around foundations. Installing a system too close to a foundation can increase the risk of potential permafrost problems, such as frost jacking. There is some question as to how a heat pump will work over time if it removes more heat from an area than can be replaced by surrounding soils and seasonal conditions, especially in Alaska where ground temperatures are cooler to begin with. On the positive side, there are methods to curb excessive cooling, such as adding a solar thermal collector to recharge the ground during the warmer seasons. This is also a proven technique, though, again, it has yet to be proven in Alaska.

Installation cost is another consideration, as the systems themselves can cost between $10,000 and $20,000. For the time being, heat pumps are showing good potential but we still need more trials in Alaska’s cold climate to give a definitive answer.

Do you have any advice for woodworking with local birch?

Birch is not used for framing and structural applications the way spruce is, but it does lend itself well to finish work. Birch has a lot of color. The heartwood can be very dark while the sapwood can be very light. In addition, the grain is rarely straight which gives the wood a ‘figure.’ After varnishing, the combination of colors and grain can be quite eye-catching. Each tree is unique and especially with birch, there can be big variations in wood appearance from one tree to the next. As examples, birch can add wonderful highlights to kitchen cabinets, and floors.

Birch is denser than cottonwood or spruce, making it better suited for stairways and tabletops. When working with birch, make sure there is plenty extra so any undesirable defects or twisting can be milled out or replaced. When it comes to panels and drawer fronts it is a good rule to varnish both sides and the edges, to keep the wood stable. As humidity changes over the seasons, moisture will penetrate an unvarnished side to a greater degree, which can cause warping.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Insulating your septic tank; identifying permafrost; putting up a wind turbine

Alaska HomeWise: Ask a Builder

By Cold Climate Housing Research Center Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Recently, I was scoffed at for wanting to insulate my septic tank when I install it next summer. How much insulation is necessary for a septic tank?

Septic tanks contain bacteria that will break down septic sludge. These organisms will do much better in a warm environment than a cold one. There is some debate on how much insulation makes a difference when it comes to soil temperature and bacteria performance. However, a bigger concern is a septic tank freezing because it was not buried deep enough, or does not have enough insulation to protect it from cold air. A frozen septic is more likely in the winters of extreme cold with little snow. In that case, the ground freezes very hard and very deep.

When in doubt, it is cheap insurance to add a layer of rigid two-inch foam insulation on top of the tank and a few feet down on the sides. In fact, insulating a septic tank is a good way to use up all the damaged or left over pieces of foam from a jobsite. Another alternative is to have the top of the tank sprayed with several inches of polyurethane foam. Do not forget to consult with the Alaska Department of Environmental Conservation for the most recent codes for insulating a tank.

Is there a way to tell if land is full of permafrost just by looking at it?

There are some visual indicators, but they are not 100% reliable when determining whether or not land has permafrost. For starters, look at the other houses in the area and the types of foundations they have. If there are a lot of houses on posts, or if houses with conventional foundations are sagging, that could be a sign of permafrost. If the land is down in the flats or on the north side of a hill and has mostly little black spruce trees and moss, that often indicates ice in the soil, because the land cannot support a big root structure. Sometimes a piece of land can have good-looking ground but permafrost underneath at a low depth or ice lenses (pockets of ice) only under small areas.

Not everywhere has a lot of wind, so when is putting up a wind turbine system practical? ?

You can still put up a turbine, but it is important to have a good wind resource. If you are connected to the electrical grid, you want to have average wind speed at about ten miles per hour or better. Of course the cost of electricity for your home will dramatically affect any possible payback of putting in a wind system. If you are in a village and paying 60 cents a kilowatt hour for power, then having “enough’” wind is going to be different than if you are in Anchorage and paying eight cents a kilowatt hour for power. Look at how much energy you are likely to produce annually, how much money you will save, and the cost of installing a system – all before deciding if a wind system is cost-effective.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Prevent heat loss with exterior insulation

By Cold Climate Housing Research Center Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

These days, it is popular to put foam insulation on the outside of buildings.  How did all this come about? 

      A building loses heat through its framing, which is called “thermal bridging.”  Wood has less insulative value than any kind of insulation.  For instance, a wood stud has an R-value of 1.25 per inch.  If a building has a standard framed wall, whether it is 2×4 construction, or 2×6 construction, the studs span from the interior of the wall to the exterior of the wall. For a 2×6 wall, that would give you an R-value of about R-7 where the stud is located.  If you were to take all the studs in a wall and stack them side by side, you would have a wall that is 11-25% wood depending on how it is built.  Even if a wall is full of R-21 fiberglass insulation, the insulative value of the wall is dramatically worse when you average in the less insulative value in the wood.

      At least 20 years ago builders began experimenting with putting insulation on the outside of homes as a way to stop heat loss created by thermal bridging. Adding foam to the outside of a wall “wraps” your home in a continuous layer of insulation, thus preventing other building materials from conducting heat to the outside and cutting down on the air leaking out of your house.  This technique has been used in many cold climate regions.  The PERSIST (Pressure Equalized Rain Screen Insulated Structure Technique) is an exterior insulation technique that has been used in Canada for many years, while the REMOTE (Residential Exterior Membrane Outside Insulation Technique) Wall System is popular here in the Interior. 

Where can I recycle glass in the interior? 

      Recycling glass is a challenge because the material is heavy and difficult to ship out of Fairbanks and then out of Alaska.  Also, Anchorage recently ended their glass recycling program, in part because the market for glass is currently not very good. 

      Here in Fairbanks, there are a few small artisan-type businesses that are reusing glass, but they cannot handle large volumes and typically have more than they need already.  However, the Borough Recycling Commission is looking at ways to use glass here locally potentially as road fill and construction fill.  These plans will take time to develop, so if you have any input, contact the Recycling Commission through the Fairbanks North Star Borough at 459-1000. 

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC).   If you have a question, e-mail us at akhomewise@cchrc.org.  You can also call the CCHRC at (907) 457-3454.

Construction industry working to limit offgassing

ASK A BUILDER

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Q: What is offgassing and is it something I need to worry about?

Offgassing, also called outgassing, is a term used to describe any chemical compounds or irritants that are emitted from something. Any building products such as plywood, paints or carpets, construction glues and varnishes can emit chemicals for extended periods after they have been installed. Offgassing is common in solvent-based or petroleum-based products. Good ventilation is an important factor in combating offgassing.

Current building codes require mechanical ventilation in new construction to ensure that a house gets enough fresh air. If you want to build an eco-friendly home, or you have chemical sensitivities, look into building a home with little to no offgassing components. In the big picture, the construction industry is changing the way it manufactures products in order to limit or eliminate the use of materials that offgas.

Q: What’s an acceptable temperature to keep my garage at throughout the winter?

If the house is attached to the garage, you will want to keep it a little warmer, about 50 degrees.

In many cases, if you have a boiler and pipes in the garage, they may warm the garage more than you want just from the heat they give off, especially if your boiler is an older unit. Since it is not living space, if you have a garage that is 70 or 80 degrees, you may be using a lot of energy to heat that space. Also, that is a lot of heat that could be leaking out through the walls, which adds up to wasted energy. Don’t heat your garage anymore than you have to because it is a wasted expense.

A cooler garage is a good place to keep a refrigerator or freezer.

Keep the temperature at 60 to 40 degrees, or whatever your comfort zone is. On that note, if you are seeing a lot of condensation in the garage, which can happen by parking a wet vehicle inside, you might want to keep the temperature a little warmer or ventilate more.

Q: If I am interested in putting up a wind turbine.

Is this something I can do myself?

Installing a wind turbine is not that hard, but you definitely want to do it right or it will become very hard and very expensive. Even if installing the tower goes well, you are talking about lethal voltages of electricity, just as in any home. You don’t have to be a trained professional to do it right, but it’s prudent to work with people who are trained to install such specialized equipment.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Get the LED out (they work well)

ASK A BUILDER

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Q: I’ve read LED lights perform well in cold temperatures. What about in Alaska?

Absolutely. LEDs are generally pretty tough. They are shock and cold resistant. In fact the colder it gets, the better they perform. When it comes to outdoor lighting at extreme temperatures, some fluorescents can suffer from performance losses when compared to their use inside. Currently, LEDs are popular in lowlight applications such as pathway lighting or for task lighting such as workbenches, nightlights, flashlights and other devices where incandescent bulbs have traditionally been used. Because small incandescent bulbs are the least efficient, they are perfect to be replaced by an LED.

When it comes to the lighting industry in general, changes are coming along quickly. Prices are coming down on LEDs and fluorescents, and they are being better designed to work in different environments. If you are looking at buying an LED light for outdoor use, get one with a good warranty. The bulbs may last a long time, but there are other components in the light that may not fare as well.

Q: What is the difference between EPS and XPS foam?

Both are similar chemically and both are made from polystyrene, but the manufacturing process is different. Expanded polystyrene (EPS) foam, also called “bead board” is what you would find in coffee cups.

It is manufactured using small plastic beads that are expanded and fused together in a mold. Extruded polystyrene (XPS) is blue or pink, hence it is also called “blue board” or “pink board.” It is also made using polystyrene beads, but they are liquefied rather than expanded and then a blowing agent is added to force the liquid into a form. This process also creates a skin on the surface of the foam.

XPS is slightly more resistant to water vapor than EPS. EPS, generally has an R-value of 3 to 4 per inch, whereas XPS has an R-value of about 5 per inch. No matter what type, the R-value will be printed on the packaging or the board itself.

It is often assumed that the blue or the pink foams are the only ones you would want to use “below grade,” such as in your basement or a damp environment. The truth is both products will work as long as they are strong enough or dense enough to handle the stress in the place they are going to be installed. For example, many insulated concrete forms are made with EPS foam. These forms always go below grade. No matter the case, consult the product manufacturer information, which is usually available where you purchased the foam. Also, judge the prices in relation to the R-value you are getting, and get a product that is rated for your application.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

Get in the know about plugging in your car

By CCHRC Staff home life.

ASK A BUILDER


Q: Is there anything I need to be cautious about when plugging in
my automobile?Q: I’ve seen that there are now roof shingles that are solar panels.While a wide range of solar technologies work in Alaska and other cold climates, photovoltaic roof shingles are still too new and untested for cold regions. The basic concept of solar shingles is excellent because the space is usually wasted and basic support structure is already in place. But remember, things perform differently in our extreme climate. If the shingles are glued on, you have to check how that glue performs in cold temperatures. When it comes to solar technology, there are some general rules to be aware of. Anything that applies to solar means you have to have a good exposure to the sun, preferable facing south.Q: What is a heat recovery ventilator and what does it do?

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of

For starters, there are the basics of electrical safety: when you are plugging in anything, you do not want to make direct contact with the circuit because of the risk of electric shock. Besides that, a lot of Fairbanks car fires can be attributed to improperly maintained vehicles. Oil leaks, fuel leaks or other heating elements can be ignited by a small spark. Because winterizing cars in Fairbanks includes installing electrical heating devices, people need to be more cautious about leaks because of the risk of fire.

So if you have leaks, get them checked out and perform any other standard car maintenance.

 

Could those work in Alaska?

 

The shingles are going to be covered with snow, so how will that factor into their

East or west might work too, depending on how your roof is built and the pitch of the roof. Consider all the options before choosing a system.

 

A Heat Recovery Ventilator, or HRV, is designed to bring fresh air into your home. The “tighter” your home is (fewer leaks in insulation, doors and windows), the more essential an HRV is to the safety of the occupants. The other important part of an HRV, heat recovery, means it captures as much of the heat that is leaving the building as possible. You have already heated the air in the house.

To bring fresh air in, you are going to have to expel stale air, but that air has heat in it that you do not want to waste. So the HRV acts as a heat exchanger. As cold fresh air moves in, the warm stale air moves out. When the two air flows pass by each other, the heat from the warm, stale air is transferred to the cold, fresh air through a heat exchanger. These devices will help keep your home warmer in the winter, while saving you energy and money because you do not have to reheat the air coming into your home quite as much.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.

How to cope with outside insulation

ASK A BUILDER

By CCHRC Staff

The “Ask a Builder” series is dedicated to answering some of the many questions Fairbanks residents have about building, energy and the many other parts of home life.

Q: What are some of the risks with adding insulation to the outside of my home?

It is a complex issue, and what works in one part of the state may not necessarily work in another. The key to successful exterior insulation is to keep moisture from entering the wall from the inside and from the outside. If you cannot ensure this will not happen, then you are insulating at your own risk. If too much moisture moves into your walls or ceiling, then you could end up with mold and rot.

For years, people in Fairbanks and other parts of the state have been applying various amounts of foam insulation to the exterior of their houses. However, this method can also contribute to moisture problems if not done correctly. These problems can originate from inside or outside the house.

In local building code, cold climate construction requires a vapor retarder, placed near the interior wall surface. Most times this consists of a well-sealed layer of polyethylene under the sheetrock.

This barrier membrane is designed to prevent indoor moisture from getting inside walls where it can condense. When you have heat and humidity inside, and a leaky vapor barrier, moisture may get inside a wall. If there are not enough outside layers of foam insulation, this moisture will cool, condense and begin causing problems. Having the proper ratio of insulation on the outside of the wall to insulation on the inside of the wall will help solve this problem.

Also, if you have a good existing interior vapor retarder and add exterior foam, you are creating, what many call, a “double vapor barrier,” as the foam is also relatively impermeable. Should enough moisture find its way into a wall under these conditions, it may have a difficult time drying out.

In some environments, there is the possibility that rain water can work its way into the wall, especially in combination with wind. To minimize these problems, your home may benefit from large overhangs, gutters and proper drainage. Another option is a good draining type of house wrap installed in combination with adhesive or metal flashings, which are applied before putting on the foam. These steps will ensure that if any water gets behind the foam, it will drain down into the ground rather than soak into your framing.

If you put exterior insulation on your house, it will become much tighter. As a result, your indoor humidity levels may increase and the house may no longer receive enough fresh air, making it necessary to better ventilate your home.

An early indicator of elevated indoor humidity levels are your windows. If you are seeing a lot of condensation, especially on a good quality doublepane or triple-pane, that is a good reason to look for a cause.

Q: Are electric stoves more energy efficient than propane ranges?

Strictly, electric energy is very efficient in a range, but it depends on what the cost of propane is, and what the cost of power is in relation. You would have to figure out how much energy, in BTUs, you are getting out of your propane and what you are paying for your kilowatt hours, and compare the two.

Alaska HomeWise articles promote home awareness for the Cold Climate Housing Research Center (CCHRC). If you have a question, e-mail us at akhomewise@cchrc.org. You can also call the CCHRC at (907) 457-3454.