This week the first members of the student workforce started at the UAF Sustainable Village site. Student carpenters helped frame in the second home (on the northeast lot)
About eight students will work on the project this summer. They all participated in a safety course this week, learning the basics of on-site safety—such as using personal protection equipment and identifying site hazards. Next week they will be taught how to use a skill saw, nail gun, chop saw, and scaffolding.
Next week we will install trusses on the northwest home. The homes will have a shed-style roof with a continuous ¾ inch air vent under the decking so heat doesn’t conduct to the roof. There will be 20 inches of cellulose insulation in the roof for an R-60.
UAF students attend a safety course before starting work at the UAF Sustainable Village.
Student carpenter Garret working with longtime carpenter Joe on the Village site.
If you are thinking about purchasing a new boiler (or any other heating appliance) in the near future, make sure that you get one that is the optimal size for your house. Correctly sized boilers operate more efficiently and are able to keep your house at a comfortable temperature. A boiler that is too small will not be able to produce enough heat in the winter months, and a boiler that is too large will cycle on and off, wasting fuel, just like a car driving in stop-and-go traffic. Here are 3 ways to know if your current boiler is the correct size:
1) The rule-of-thumb: On the coldest day of the year, your boiler should run pretty much non-stop to keep the set temperature. Think of it as a car driving on the highway, getting a high miles-per-gallon since it doesn’t have to start and stop. If it does run non-stop, but your house does not stay warm, then the boiler is undersized. On the other hand, if you find your boiler cycling on and off during January’s coldest week, then you should consider getting a smaller boiler.
2) The calculations method: To determine what size of a heating appliance you will need, in addition to finding out information about what other energy upgrades you can make to your house, consider signing up for an energy rating. An energy rater will look at your entire house, measuring the air leakage rate with depressurization from doors and windows, checking insulation levels, assessing your heating system and checking for drafts. They will input this information into AKWarm, software maintained by the Alaska Housing Finance Corporation that calculates energy ratings. In a few weeks, you will receive the rating in the mail. It includes ways to improve the rating and other information on your house, such as the heating needs. An energy rating typically costs between $425-$550, but this will be rebated if you participate in the Home Energy Rebate Program (though you will likely face a waitlist for the rating). Visit the Alaska Housing Finance Corporation website for information on the rebate program and signing up for a rating: www.akrebate.com.
3) Do-it-yourself: The rating software AKWarm is available for free online. If you are computer-savvy and have a few hours to gather information on your house, you can use AKWarm to calculate your own unofficial energy rating. The software is available for download here: www.analysisnorth.com/AKWarm/AKWarm2download.html.
We’ve made a lot of progress on the Sustainable Village this week—framed the first floor of the northwest house, started building the deck for the second floor, and poured concrete slabs for the two east homes.
The first floor of the first house was framed in a day. The 1,500-square-foot home has four bedrooms, a downstairs bathroom, upstairs kitchen, and big south-facing deck on the second story.
The beginning of the week was cold with scattered showers, so the concrete contractors waited until Thursday and Friday to pour slabs. The process took about two hours—the mixing truck and the pumping truck showed up and one of the guys poured the coloring (Santa Fe) into the mix. Then five guys worked together on the floor, spreading the “mud” from a rubber hose, moving it around with “mud sticks,” leveling the slab with a screed (or flat board), and smoothing and sealing it with a bull float (a long-handled tool with an aluminum float). Once the slab set up a bit, they went over it with a trowel (a flat, metal-bladed hand tool), which gets rid of any bumps and gives it a smooth finish. The slab is 1.5 inches with a pretty adobe color.
The crew is currently framing the second story. Next week students begin helping out on site.
pouring the concrete slab for the southeast home
radiant tubing within the concrete slab
spreading the “mud”
mixing truck pours cement into concrete pump
pouring cement-a team operation!
screeding, or leveling, the slab
bull floating, or pushing the gravel to the bottom and the “cream” to the top
During Week 3, we built floors for the two homes on pilings and laid radiant floor tubing. The homes will have concrete slabs and and about 10 inches of under-floor spray foam insulation.
Two of the homes will have insulated raft foundations. This allows the house to rest directly on the ground, keeping the floor warmer than if it were elevated on piles. A thick mat of spray foam is designed to prevent heat loss from affecting the frozen ground, and a cooling system was also installed in the gravel pad to chill the soils if needed.
CCHRC is demonstrating an innovative foundation design at the Sustainable Village. Two of the homes, sitting on permafrost about 9 feet deep, will be built on steel piles, a common method for building on frozen ground. The other two, situated on stabler soil, will have an insulated mat foundation.
Builders laid the mat foundations last week. They include a geotextile mat placed directly on the soil with several feet of gravel on top. PVC pipes are embedded in the gravel in a grid formation as a backup cooling system. Resting on the pad is a steel floor assembly. Spray foam was applied against the entire system for a monolithic layer of insulation at least 10 inches thick. This is designed to prevent heat from inside from transferring to the ground. Temperature sensors were strung about 10 feet down into the soil to monitor any changes. If needed, cold air could be circulated through the piping system in the winter to lower the temperature, as insurance against shifting ground.
The UAF Sustainable Village broke ground on Friday, April 6 on lower campus near the Cold Climate Housing Research Center.
The development will feature innovations in cold climate construction—with super-insulated building envelopes to minimize heat demand—as well as experimental approaches to energy, ventilation and wastewater treatment. The homes will serve not just as student residences but also as housing prototypes, building science labs, and teaching tools.
UAF students helped CCHRC develop the concept for the homes, through a design contest, and will help build and conduct research on the Village as well.
“The thing that’s unique about this project is it’s engaging students for the first time in the development of sustainable housing,” said Michele Hébert, who heads the UAF Office of Sustainability. “Our hope is that this will lead to more young people learning how to live sustainably and be future leaders in sustainability.”
The 1,500-square-foot homes will have an R-50-60 envelope and will use a mix of solar, biomass and conventional fuel. A 14 kw photovoltaic array was funded by the university sustainability grant.
The project will demonstrate that a highly energy efficient 4-bedroom home can be built in Fairbanks without breaking the bank. The budget is approximately $200,000 per home. The rent will approximate the cost of a mortgage for an equivalent new single-family home in Fairbanks and be competitive with dorm rates.
Construction will be done by seasoned carpenters along with UAF student workers. Student residents move in in mid-August, so we will be busy for the next few months!
A pile driver hammers hammers a steel round into the ground, part of the piling foundation.
UAF Chancellor Brian Rogers describes what the Village means to the university community.
UAF Sustainable Village breaks ground on April 6, 2012 next to the Cold Climate Housing Research Center
CCHRC President Jack Hebert along with UAF Chancellor Brian Rogers share their goals for the Village.
Lyle Axelarris participated in the student design competition and helped CCHRC design certain aspects of the Village.
Students proposed ideas and concepts for the Village through a student design competition.
CCHRC is working with an education center in Bethel to help improve the energy performance of its new building.
Yuut Elitnaurviat is a vocational center that offers training in construction, health care, dental health aid, and other subjects for residents of the Yukon-Kuskokwim Delta region.
The new building at Yuut Elitnaurviat campus consumes more than 40 percent more than the average building in Alaska.
The school is spending more than 40 percent more than the average commercial building in Alaska for heating and power at its facilities—which includes a classroom, admin offices, a cafeteria, dormitory and shop—and the building is only a few years old. This stems from inefficiencies in heating, lighting, and ventilation systems, among others. For example, the air handling system is consuming more than its fair share of energy use and may be oversized for the building. In addition, the school is paying to heat much more domestic hot water than it actually needs.
CCHRC researchers visited the campus in March to explore options for improving the building’s performance.
“They’re paying almost 50 cents a kWh, and they’re using around 32,000 kWh a month, so it makes more economic sense to focus on the electric load than on space heating at this point,” said CCHRC research engineer Bruno Grunau.
CCHRC prepared a feasibility study of the local resources and found both wind and solar photovoltaic systems would be viable technologies. Researchers are now helping school officials plan a small wind farm and solar array. The wind farm could include up to 4-5 turbines, each producing approximately 6,000-10,000 kWh per year, and a 10 kW PV array that would produce approximately 8,500 kWh a year.
Building officials are also pursuing a commercial energy audit to find other economical ways to save energy, such as tightening the building envelope or installing high-efficiency lighting and daylight sensing.
