COMMITMENT TO GREEN TECHNOLOGY
Mandala Custom Homes is dedicated to creating positive change in the world through innovative green technology and a focus on using safe, healthy and sustainable building products.
NON-TOXIC WOOD FINISHES
Mandala Custom Homes uses non-toxic finishes to bring out the natural beauty and grain of our wood siding, paneling and timbers.
LifeTime finishes are free of poisonous or toxic ingredients. Friendly to plants, animals, and people, LifeTime can be used in direct contact with garden soil. The natural substances in LifeTime Wood Treatment penetrate the wood fibers, permanently modifying the wood structure, creating a beautiful, naturally aged appearance that many wait years for.
CBR’s Broda? line has been Eco-Certified by Canada’s Environmental Choice Program. The outstanding characteristic of Broda Wood Pro-Tek-Tor is its base of natural oils and resins. These natural ingredients, combined with water, provide exceptional protection; bonding with the material it is applied to and hence safe for the environment. Mandala Custom Homes offers Broda stains in a variety of colors.
ENERGY EFFICIENT ROUND HOME DESIGN
Round homes use less wall area to enclose the same square footage as a rectangular building resulting in less BTUs to heat than a conventional home. Mandala Custom Homes’s weather-tight design provides a strong barrier from the elements, limiting air leakage and vastly cutting down on heating and cooling costs.
ENERGY EFFICIENT INSULATION PACKAGES
Mandala Custom Homes’s optional insulation packages include formaldehyde-free insulation. You have the choice to upgrade the R-Value of your insulation package.
BUILDING A FOUNDATION THAT COUNTS
When you say you want a foundation that will save energy, last a lifetime and create a noiseless barrier to the outside, we tell you about Insulated Concrete Forms (ICF). ICFs are made from rigid foam and are energy-saving and easy to install.
Mandala Custom Homes encourages you to integrate the use of alternative power sources into the design of your pre-designed or custom Mandala Home Kit. Please contact a Mandala Homes Sales Representative for more information or referral for the installation of solar, wind or micro-hydro power on your property.
The most energy efficient heating system for your home depends largely on where you live, since both climate and access to fuel affect a given system’s efficiency. That being said, here are some general guidelines for home heating systems:
Electricity: Heating with electricity can be very efficient (converting electricity into heat is almost 100% efficient), but only if your electricity comes from a green power source (hydro, solar, wind, etc.). If your power comes from coal or gas, the original conversion of fossil fuels into electricity is extremely inefficient, making electricity a poor environmental choice. Other factors to consider when heating with electricity are escalating costs and the fact that, by using more power to heat your home, you may contribute to your utility being forced to build a non-green power source at some point in the future.
Gas: Modern gas heating appliances can be very efficient at converting gas into heat (better than 90% efficiency for the best ones), but the energy required to originally extract that gas from the earth and then process it detracts from any on-site efficiencies. What’s more, natural gas is still a fossil fuel, and burning it contributes to climate change, to say nothing of projected price increases in coming years.
Woodstoves: Wood heat has many advantages if the wood is burned correctly. Modern woodstoves have efficiencies of 70–85% and produce just 2–5 grams of smoke particulate per hour (compared to 40-80g per hour for older woodstoves). Wood is also considered a carbon neutral fuel, since burning it properly releases only as much carbon dioxide into the atmosphere as that tree sequestered during its lifetime (compared to burning fossil fuels, which releases carbon dioxide that has been stored for millions of years). However, wood that is burned poorly (either wet wood or wood that is allowed to smoulder) releases larger amounts of both greenhouse gases and smoke particulate into the atmosphere. The former is bad for the planet; the latter is bad for local air quality.
Masonry Stoves: Masonry stoves have been around for centuries in Europe and are beginning to make a bit of a resurgence. Essentially, a masonry stove consists of a large thermal mass (usually either brick, concrete or stone) surrounding a firebox. The firebox is connected to the chimney by a specially designed passageway that a) re-ignites the smoke on its way through, allowing the masonry stove to reach efficiencies close to 90%, and b) enables the surrounding thermal mass to absorb the vast majority of the heat before the small amount of smoke rises out of the chimney. The large thermal mass then slowly radiates that heat for 12–24 hours after the fire is finished. As a result, masonry stoves are not only extremely efficient, but they allow homeowners to light a quick, hot fire in the morning and another at night, with no need for stoking during the day. Some masonry stoves even come with a built-in oven above the firebox, which is perfect for slow-roasting a pizza. Traditionally, masonry stoves were built by skilled stone masons, but few masons in North America are familiar with the technique, and it is essential that the firebox and chimney be built to exact specifications. However, it is possible to buy commercial masonry stoves (www.tempcast.com; www.tulikivi.com) that take the guesswork out of the process. The only downside of masonry stoves is that they are relatively expensive, and they require a very solid foundation to support their significant weight (making them tricky to retrofit). Overall, however, they are one of the most environmentally friendly heating systems available.
Pellet Stoves: Wood pellet stoves are very efficient (up to 85%), and have the added advantage of burning recycled sawdust as a fuel. The sawdust is carbon neutral, and a modern pellet stove’s smoke emissions are equal to or lower than those of modern woodstoves (see above). What’s more, pellet stoves can burn 24–48 hours with a single hopper full of pellets, and many come with a thermostat that regulates how quickly the wood pellets are fed into the fire. One thing to consider is where your fuel comes from and how reliable that source of fuel is. Wood pellets that are shipped from half a continent away may not be all that green by the time they reach your home, and if your local hardware store stops carrying them, finding substitutes may be tricky. In addition, pellet stoves require a small amount of electricity to feed the pellets into the fire.
Corn/Wheat/Rye Stoves: These stoves are becoming more common in farm areas where access to fuel is straightforward. In most cases, the fuel needs no special processing (although the corn must be dried) and can be bought straight from a farmer. In terms of efficiency and ease of operation, the stoves function much the same as pellet stoves, and some can even handle both grain and wood pellets as fuel. The grains are considered carbon neutral and have the added advantage of only taking one year to grow. As in all fuels, however, there are environmental costs associated with getting the fuel to your door – in this case, the fuel used by the farmer to power his equipment, as well as the petroleum-based fertilizers and pesticides that may have been used in cultivation.
Geothermal: Geothermal heating is not a fuel on its own, but it greatly improves the efficiency of other fuels. Essentially, geothermal heating (and cooling) takes the latent temperature of the earth (or a large mass of water) and uses heat pump technology to make that temperature warmer or cooler. Geothermal systems generally consist of a series of underground pipes and a heat pump. The pipes pick up the temperature of the ground or water (a year-round temperature of 7–13°C) and compress it to produce heat or expand it to produce a cooling effect. The advantage of using the ground or water is that it starts at a significantly warmer temperature than the outside air temperature in winter, and in summer it is much cooler than the air temperature. Although an external energy source (usually electricity) is required to run the heat pump, it can reduce power consumption by between 25% and 70% compared to conventional heating and cooling systems.
In-Floor Radiant Heat: In-floor radiant heating and cooling consists of either an electric heating blanket underneath the floor, or a matrix of pipes running through the floor. Water, or a mixture of water and antifreeze, in the pipes can be heated and cooled by any number of methods, and the system is a method of heat delivery rather than a heat source by itself. The environmental benefits of in-floor heating are two-fold: 1) Because the heat radiates from the floor and through people’s feet, most people feel comfortable with their thermostat set 1–2°C lower than with other kinds of heat; 2) Radiant heat reduces allergy issues often associated with the blowing air (and dust and mould) of forced air heating systems. What’s more, radiant heat produces a more uniform, constant heat, instead of the cycling of warm and cooler air often associated with forced air heating.
Passive Solar: In most climates, passive solar design is not enough to be a home’s sole source of heat, but it will likely be able to reduce your home’s heating needs. Since passive solar heating relies on direct sunlight, it helps to live in a region that receives significant amounts of winter sunshine. See our webpage on Passive Solar Design.
Annualized Geo-Solar: Annualized geo-solar is a method of storing the sun’s summer heat and re-using it in the winter. It has been used at the community level in Okotoks, Alberta (www.dlsc.ca), but it can also be used at the single home level. All that is required is a method of absorbing the sun’s heat, a method of storing it and a method of redistributing it. Absorbing the heat can be done with solar hot water panels on the roof, or with a greenhouse attached to the house. A very large thermal mass can then be used to store the heat for months at a time. In some cases, the ground directly underneath the house is used as the thermal mass, with the summer heat being pumped through the ground at a depth of 2-3m under the house. This mass also acts as the heat delivery system, as the heat slowly rises through the ground, ideally taking approximately six months to reach the house’s un-insulated floor. According to some experts, a well insulated house can reach a winter temperature of 20°C after two to three years (it takes a few years to accumulate that much summer heat). The ground underneath the house must also be insulated and protected from the leaching effects of rain in order to avoid losing the stored heat into the surrounding soil. Although this heating system has the potential to provide free, pollution-free heat, it is still relatively experimental and should only be undertaken by those people comfortable with experimental green building techniques.
PASSIVE SOLAR HEATING AND COOLING SYSTEMS
Passive Solar Design refers to the use of the sun’s energy for heating and cooling a space. Many of the basic principles of passive solar design have been around for thousands of years, but had until recently been largely forgotten by the western world due to our ability to use artificial means to heat and cool our homes.These principles include:
- orienting buildings along an east-west axis
- ensuring that south-facing windows receive sun between 9am and 3pm during the heating season
- organizing interior spaces so that those areas requiring the most heating (living room, etc.) are directly exposed to south-facing windows; rooms with lower heat requirements should be located on the north side of the house
- using an open plan design to allow warmed air to circulate
- using roof overhangs to shade south-facing windows from strong summer sun
- minimizing windows on east– and west-facing walls to reduce unwanted heat gain in summer, and on north-facing windows to reduce heat loss in winter
- building “thermal mass” into the home so that the sun’s rays can be absorbed and later radiated as heat (thermal mass refers to dense materials that store and release heat slowly – concrete, stone, water, etc.); thermal mass can also help moderate a home’s temperature during hot summer months
- locating operable windows to catch prevailing summer breezes
Designing your house according to the principles of passive solar design has many benefits:
- increased occupant comfort
- less energy consumption
- lower heating and cooling bills
- reduced greenhouse gas emissions
- less reliance on external sources of energy
At Mandala Custom Homes, we do our best to incorporate passive solar design in all of our buildings. However, many aspects of passive solar design depend on specific characteristics of the building site, such as prevailing winds, orientation of the property, existing vegetation, slopes, etc. Please ask us for more details.
Note: Solar Hot Water heaters are also considered part of Passive Solar Design, but they are covered in their own section.