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Greenovision Spring 2015 Newsletter: Earth Month Edition!

We recently published our Spring 2015 Newsletter. In this edition, you can view renderings of our latest home design, learn about the environmental impacts of the housing industry, and read our article, “Energy-Efficient Heating Options for the Modern Home,” that was published in Bozeman Magazine.

To view this newsletter, please click here. To read our previous newsletters, click Past Issues on the top left corner of the newsletter. That top bar also has a sign up form to subscribe to our quarterly newsletter.

“Bozeman Magazine” Article: Energy-Efficient Heating Options for the Modern Home

BozemanMagazineCoverGreenovision is happy to share an article we wrote for Bozeman Magazine’s April 2015 Environmental Edition entitled “Energy-Efficient Heating Options for the Modern Home.” Please click here to view the article on the Bozeman Magazine website or read the reprinted copy below.

Energy-Efficient Heating Options for the Modern Home

Written by Mark Pelletier and Emily Varmecky

Edited by John Burbidge

Construction of new homes is on the rise again in Bozeman. According to the Sonoran Institute, a non-profit community planning organization, by 2026 Gallatin County could add as many as 26,000 new homes. As traditional fuel sources become more expensive and home energy costs rise, it is important that new homes are built to be energy-efficient now, so that we can afford to live in these homes in the future. Spending more up front on energy-efficient design, technology, and materials will ultimately result in a more affordable home over time because the yearly savings on your energy bills will exceed the costs of the additional design and infrastructure.

It is important that homeowners, not just home professionals, have a clear understanding of how their home is designed, built, and operated. Empowering yourself with the knowledge of energy efficiency will help when choosing a designer, builder, and other home professionals for the construction of your new home. The generation, distribution, and storage of energy is of particular concern to home energy specialists, so we’re going to break down home energy to help you have a basic understanding of how energy is used within your home.

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The three demands for energy within a home are: heating of your home spaces (accounting for about 49% of home energy usage), electricity for lighting and appliances (36% of home energy usage), and lastly hot water for bathing, doing dishes, and laundry (16% of home energy usage). The majority of homes in Montana have a power meter that provides the electricity, a domestic hot water heater (that big cylinder down in your basement), and a forced air furnace for home heating. In other words, most homes are 100% reliant on energy that is produced outside of the home.

These conventional “grid tied” energy systems are now considered inefficient and unsustainable for many reasons. Most conventional water and space heating systems, considered outdated by many home energy experts, are under-insulated, stored in cold “unconditioned” spaces, and lose heat through the duct systems that distribute the heat throughout the home, called a “standby loss.” These conventional heating systems are losing heat almost as fast as they’re producing heat. Combine inefficient heating with a leaky, under-insulated home envelope (like many homes have), and you’ve got a recipe for high home heating bills.

Since home heating accounts for about half of residential energy consumption in Montana, it’s worth delving into the specifics of energy-efficient heating a little further. (Methods of lowering your electric and hot water heating bills, as well as alternative methods of producing the energy for these two systems within your home, are great topics for follow-up articles.)

One of the best ways to minimize heating energy needs within the home is to comprehensively contain the heat that this is being produced. Designing and constructing your home with materials that have high insulation values is important for keeping heat in during the winter, thus reducing the amount of heating energy required. Likewise, in the summer insulation helps to keep heat out of your home reducing air conditioning costs. Advanced framing techniques reduce thermal conductivity (aka “cold bridging”) from the outside to the inside (or vice versa) and keep the home tightly sealed. Advanced, quality construction incorporated with high “R-value” insulation in the roof and walls as well as well-insulated windows and doors all help to minimize the total amount of energy that is needed to heat the home.

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Insulation will allow you to downsize your heating system and focus on energy-efficiency. Once you have a tight building envelope, you can next analyze the assets of your home site and develop ways to integrate them into the design of the home. Since we have ample sunlight in Montana, integrating a passive solar strategy can help lower home heating costs by 30-50%. In this system, windows, walls, and floors are designed to collect, store, and distribute the sun’s natural radiant energy in the form of heat in the winter and reject solar heat in the summer. In order to harvest the solar radiation, sunlight enters the home through carefully designed windows and the energy is captured and stored in a concrete slab floor. Over the course of a day, the slab is gradually heated by the sun, then throughout the cold nighttime hours, the thermal mass of the concrete floor slowly releases this heat, warming the interior space above it. This process is passive; it requires no plumbing or wiring, just good design.

If you choose not to implement passive solar strategy, there are a variety of other naturally occurring heating options. Geothermal heating is an energy-efficient option, as is electric heating powered from solar panels, but those systems are topics in themselves and we won’t be discussing them here.

Another home heating option is to use water, called “hydronic heating.” Water can be heated and distributed around the home through baseboard heaters, radiators, or a radiant floor to heat the spaces of your home. Water is a relatively good medium for heat storage because, unlike air, it has mass.

Regardless of which distribution system is used, the hot water is typically heated either in a tank or with a “tankless on demand” heater and is fueled by propane, natural gas, or electricity. The efficiency of hot water tank heaters varies. The tanks usually heat and store 20-80 gallons of water all the time, even when the water is not needed. An “on demand” system, on the other hand, heats water exactly when it is needed rather than heating the water in advance and storing for later use. Since the storage of heat (and subsequent heat loss) is mostly eliminated, an Energy Star rated “on demand” heater is usually more energy-efficient.

The efficiency of hot water distribution also varies. With baseboard heating and radiators, hot water travels in around the home in ducts and heat emanates from the water that is passing through the baseboard or radiator. Heat loss often occurs in the conduit systems if they are not insulated properly. Baseboards can be unsightly and take up space within the home while radiators can be more compact and fit on wall spaces.

Another hydronic heating system is radiant flooring. With this system, hot water is circulated through tubing (usually called “pex,” a plastic tubing) within the radianttubefloor system; the water then heats the mass of floor, which then radiates warmth into the home from the floor up. This doubly improves efficiency as there are two mediums that are storing the heat: the water and the floor.

There are two types of radiant flooring. One method is to staple the hydronic tubing within a conventional framed floor system of plywood, floor joists, and fiberglass or foam insulation. While this is a very efficient home heating system, concrete has better thermal conductivity than wood. Therefore, the most efficient hydronic system is a radiant concrete floor, which has more mass than wood and therefore more heat storage capacity. Heat is stored and emitted very efficiently within concrete or stone without having to constantly reheat it. With a thin slab radiant concrete floor, the hydronic tubing is stapled on top of the floor system and 1.5 -2 inches of concrete is poured over that tubing. With “slab on grade,” 4” inches of concrete is poured over pex sitting on top of rigid foam insulation.
There are pros and cons to a thicker or thinner slab. The thicker the slab, the more heat storage potential. However, a thicker slab can cause a “thermal lag” with hydronic radiant heating because with more mass the floor is slower to respond to heating or cooling.

If you have incorporated passive solar heating into your home and have a concrete slab, you can maximize energy-efficiency by also integrating hydronic radiant heating into that slab. With this approach, solar heat is passively collected, then is actively distributed throughout the home by the hydronic pex conduit. The hydronic heating component of this strategy acts as a good back up heating option if there is a long stretch of sunless, non-solar degree heating days. Also, if you do choose to go with a hydronic home heating system, that same heater can often be used to also heat your domestic hot water, simplifying the number of heating systems you have. Of course, with any heating system that you choose, you want to make sure that it is a very energy efficient “Energy Star rated system.”

As you can see, there are a variety of energy-efficient home heating methods that can help lower your home energy costs. Now that you have a better general understanding of home heating, be sure talk with your designer, builder, and subcontractors and ask them about their specific energy efficiency strategies.

New Passive Solar Home Design and Models: Crimson Bluffs Home

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Greenovision is pleased to announce that we are working on a design for another new home this winter 2015. The Crimson Bluffs Home will be located in Townsend, Montana on the historic Lewis and Clark Trail, which overlooks the Missouri River. At about 2200 square feet, this contemporary two story home (plus attached garage) is designed for passive solar heating and passive cooling strategies.

Upon entering the home from the west-side entrance, you can sit on the built-in bench to remove your shoes and take off your coat. This foyer/mudroom area will have custom built-in cubbies and a closet for storage of seasonal clothing, shoes, and gear. A door to the north of the foyer leads to a small and quiet studio/office room. Exiting the foyer to the east, you will walk into an open floor plan which includes the kitchen, dining room, and living room. You’ll immediately have stunning views of the Big Belt Mountains to the east and the Crimson Bluffs to the south. Views of the Missouri River can be seen just down the hill to the east and northeast. You can exit the living room area to a large outdoor deck located on the east side of the main floor. This deck, with deep roof overhang, will be a cool and relaxing place to sit outdoors during the warmer months. Views of the Missouri will be especially prominent from the deck. The main floor also includes a half bathroom, a walk-in pantry, and a stairwell leading to the lower floor.

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The lower level includes a master bedroom with master bath and walk-in closet, a guest room, a guest bathroom, and a large, sunny family room that can double as another guest room. There is also an unfinished room for storage, laundry, and the home’s mechanical systems. One can exit the family room to the south and sit outdoors in a sunny patio area. This patio will be a warm place to soak in the sun during the winter as it will be protected from the cold, northerly winter winds.

We recently completed the design and models for this home (seen here), but please stay tuned as we work on the rendered models. The renderings will provide much more realistic views of the interior and exterior of the home and will let us see how the home will look on the site. Construction is slated to begin in fall 2015!

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New Design: Quinn Creek Home

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We at Greenovision are excited to be working on a new design for a home that will be built on Quinn Creek Road, just outside of Bozeman. This is a 2500 square foot passive solar home (plus garage) that that will be nestled into the Bangtail Mountains. The homeowners will have spectacular views from within their home of the Absaroka and Gallatin mountain ranges. We have posted some renderings here of how the home will be located on the site; the siding materials are likely to change.

When you enter the home from the north, you’ll be greeted not only with an open floor plan, but an immediate view outdoors. The dining room, living room, kitchen, 1/2 bathroom, and an integrated mudroom with storage area are located on the top floor. The stairs to the ground floor are located in the center of the building and the stairwell will be illuminated with natural sunlight. The ground floor includes an exercise area, a guest bedroom with bathroom, an office, a reading room, and a laundry room. A few steps down from the ground floor is the master bedroom area, its own module secluded from the rest of the home. This area includes the master bath, a walk-in closet, and a large bedroom with stunning mountain views to the south and east.

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Situating the home onto the site has been a challenge, but we love a good challenge at Greenovision. The homeowners have 20 acres at an elevation of 7200 feet, which seems like a lot of space for situating the home, however, most of the site is at 16-20% down-sloping grade. This is a very steep grade and makes for a driveway that is barely drivable when covered with snow or ice. A driveway of this pitch can also be challenging for construction equipment to access. We needed to find a home site near the top of their property to minimize driveway length and to maximize solar gain exposure and mountain vistas. We also needed a spot that was not too steep of a slope and was far enough back from property setback lines. We had to test out a couple different home locations. Our original site required a driveway that was just too steep and also would have required a tall concrete retaining wall, which would not have been a good use of budget. Trying out different possibilities is crucial in home design to help solve difficult problems. In the end, we came to a practical and affordable solution and our clients are pleased with our problem solving.

The Quinn Creek home is designed and will be built to be energy-efficient, with passive solar and passive cooling strategies. We are pleased to have put a great team (general contractor/builder, geo-technical engineering company,  surveyor, and excavator) together to help with the project.  Some excavation work began in fall 2014 and construction is slated for spring/summer of 2015. Stay tuned!

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Greenovision Featured in Local Publications

We recently did some writing for two local publications!

Please check our article on passive solar homes in the Bozeman Magpie Magazine:

Bring On the Sun: Homes keen to solar rising in Bozeman

We also wrote a tidbit on energy efficient homes for The Bozone that was printed in the March 15, 2014 edition. Unfortunately,  that edition is no longer available to view online, so here it is reprinted below:

Energy Efficiency 101

True story: We recently ran into some Bozeman friends who told us that they’ve spent $25,000 in the last four years on their home energy bills. That’s enough money for a down payment on a new home! Thinking that their electricity consumption was the main source of their high-energy costs, they purchased a solar panel array last summer. However, come winter, they saw no significant reduction in their energy bills.

They realized that it was the heating of their home that was so costly. Now they are going through the expensive and messy process of tearing apart their roof to add more insulation. They admitted that when looking for a home ten years ago, they wish they had just built a new, energy-efficient home in the first place.

In the long run, it would have saved them money and certainly would have saved them the anguish of an energy remodel. If you need to go through an energy remodel yourself or are interested in designing and building a new, energy-efficient home, here are five tips to keep in mind:

1. Design for passive solar heat gain. The sun is a free heating source, so why not tap into it? In passive solar home design, windows and floors are constructed to collect, store, and distribute solar energy in the form of heat in the winter. Through proper design, solar heat is rejected in the summer to prevent over heating. Orientation of the house to the South, correct window types and heights, adequate roof overhangs, heat-retaining mass (such as radiant concrete flooring), and air exchange are just a few of the important components of a passive solar home.

2. Design to reduce your home energy needs. While investing in renewable energy technologies such as solar panels and liquid solar arrays is important for off-setting your home energy costs, it is equally important to design your home to consume less energy in general. Think of the Three R’s: Reduce, Reuse, and Recycle. Designing a home with plenty of well-insulated windows not only provides views of the outdoors from within, but also allows ample sunlight to enter the home. By illuminating rooms with natural light, you eliminate the need to run energy-consumptive light bulbs during the day. The same windows can be designed into the home to promote natural airflow and ventilation. This passive cooling strategy reduces the need to run electric air conditioners and fans in the summer.

3. Build with high-insulation, quality, and long-lasting materials. Building and designing your home with a high insulation value is important for keeping heat in during the winter and out during the summer. Calling for advanced framing techniques reduces thermal conductivity and helps keep the home tightly sealed. By building with quality, long-lasting materials, you reduce unnecessary repair and maintenance to your home, which ultimately saves money and is better for the environment. Quality materials also often contain fewer off-gassing toxins, which results in a healthier living environment.

4. Don’t throw beauty out the window. If you have decided that energy-efficiency is a priority for your new home, it doesn’t mean that you need to settle for a “generic-looking” house. Contrary to popular belief, energy-efficient homes can be beautiful and comfortable. Your home interiors can be designed and decorated to suit your personal tastes while being highly functional at the same time. The exterior appearance of your home can be an aesthetically engaging addition to your environment.

5. Hire a home designer that is skilled in energy-efficiency design strategies. Most designers and architects have a certain niche; be sure to find a professional that is experienced in energy-efficiency. It is always more difficult to make energy improvements on a home that is already built, so it is important to implement energy efficiency strategies and technologies while the home is still in the design phase. Spending more up front on energy-efficient design, technology, and materials will ultimately result in a more affordable home because the yearly savings on your energy bills will exceed the costs of the additional infrastructure.

Mark Pelletier and Emily Varmecky are co-owners of Greenovision Home Design. At Greenovision, we custom design beautiful, energy-efficient homes that stand apart from your neighbors. We believe that cookie cutters are for making cookies, not for home design!

 

 

 

Wood stove heat exchanger, pretty hot


I  want to report some news about the integration of a wood stove heat exchanger into my brother’s shop, WerkHaus (see the project here), that I designed and built.
Yep, my brother has finally finished off the heating system with the help of Norm Walters, a radiant heating tech. Its kind of exciting because its the final product of a giant experiment started about 4 years ago. To get the overall picture of the scheme of the heating system, please see this pic first. Oh, and this one, too.  These diagrammatically say a lot about the general idea we had years ago.
Originally we started with radiant heat tubing in the concrete slab and Phil used a wood stove up until this fall to heat the building using the fan systems to move heat around the building. This really was lacking though because Phil has to work on cars while on a dolly on the slab, which is really kind of cold down at that level. So, he knew that getting the slab up and running as the heat source would be the ultimate solution.

Phil is on a budget, so a typical on the wall, on demand propane condensing boiler was out of the question, at least for now. Originally Phil and I came up with an idea…What if the wood stove came with a heat exchange manifold? Would this do the trick and provide enough heat to run the slab? Well the answer is yes, but it isn’t quite that simple. Norm Walters filled Phil in on the possible scenario that might make it all work. What it comes down to is you need a tank to store the heat and this tank it was decided needed to be well insulated and preferably do some heating, too. So a couple of years ago, Phil purchased this unit.
Then he had Norm hook up his wood stove, which came with a very simple heat exchange coil by using a typical manifold and pump system like this…. Well to make along story short, he got this hooked up to the slab with a typical manifold system and ran it straight off the wood stove, but guess what? It just wasn’t enough of a heat coil on the stove to make it work or run warm enough. So, he resorted to running off the electric hot water heater, and guess what? His electric bill went nuts. So, Norm found a copper coil from some old refrigerator unit and installed it on the top of Phil’s wood stove to increase the heat capturing capability of the stove and water tank. I am making this sound all quite simple but in reality, it took some fiddling and some pumps, and gauges, and sensors, thermostats, and electric meters to make it all work, along with some rather confusing diagrams…I can’t figure it out too much, but what I do know is that Phil is quite happy with the fact that he is running his concrete slab with the wood stove and looks to save some electricity this winter. He sounds kind of excited about it and I would have to say that makes me happy. With some work, it is possible to make these systems happen and it does help to have a radiant heat techy on hand like Norm.

See if you can figure it all out from the the pictures I provided. I understand the concepts, but am not really on top of the electrical and plumbing part.  I believe with the proper research, the integration of a wood stove heat exchanger into homes could save on the heating in your home, too.