Radiant heat flooring warms a room by allowing warming tubes just under the floor’s surface to send heat upwards from the floor itself. At this point, it’s one of the most energy-efficient ways to heat a building, standing far ahead of conventional forced-air central heating and radiators. In fact, it so efficient that it’s recommended by the Passive House Institute, which we wrote about recently here.

With traditional forced-air central heating, warm air is blown into the room and immediately rises to the ceiling—making for a lovely warm ceiling (which nobody needs), but cold floors. Radiant heat, on the other hand, takes advantage of heat’s natural tendency to rise, making the best use of its journey upward by starting at the lowest point in the room. This process is generally far more efficient than any other form of heating, heating the room faster, keeping it warm longer, and allowing the thermostat to be set to up to 8 degrees lower than usual to obtain the same level of warmth. This results in not only lower energy bills, but less fossil-fuel consumption to provide the power that most heating systems require.

An added benefit of radiant heat is that it doesn’t dry out the air the way radiators and forced-air central heating systems do, so there’s less need for electric-powered humidifiers. But possibly the best thing about radiant heat is that it keeps your feet warm—no more freezing tootsies when you first get up in the morning!

Among its many other green products related to keeping your home warm efficiently, Green Depot carries various components for a radiant heat flooring system. The Complete Radiant Panel is an easy-to-install, modular panel with heating tubes built in, for quick sub-floor assembly. Warmboard Radiant Heat Subflooring is plywood subflooring with grooves for heating tubes pre-cut, and Tyroc is a super-insulating overlayment for cold, damp concrete floors that you can lay your radiant heat flooring panels directly on top of. And soon to be added to the lineup is NuHeat, a system of soft mats with heating elements built in—sort of like an electric blanket for your floor. Neat, huh?

(Well, for one thing, some are due to expire!)

While retrofitting a house or apartment can provide substantial energy savings – and, by extension, ecological benefits – many people worry about the initial costs of retrofitting a home.  The cost of insulating a home, buying new energy-efficient appliances, or even installing a renewable energy system, can entail a substantial investment that is sometimes beyond the means of the average person.

Acknowledging this dilemma, however, both state and the federal government have in place numerous rebates and tax exemptions to incentivize homeowners to upgrade their homes and appliances.  Utility companies and state agencies – like ConEdison and NYSERDA – also have incentive programs.  The kinds of rebates for homeowners are diverse – there are literally hundreds of them, and the process of wading through them can be daunting, to say the least.

But why care? Why are rebates important, and would it be worth the effort to determine which rebates a homeowner is eligible for, considering the overwhelming number of options available?

Of course, the answer to this question is that it is entirely worth it.  Put frankly, these programs are free cash for investment.  In the short-term, rebates and exemptions save the homeowner up-front costs for buying green products like high-efficiency washers, driers, and other appliances; and they can bring the cost of installing even the most advanced systems, like photovoltaic panels, within the reach of the average American.  In the long-term, having these products in the home not only saves money, but natural resources like water and fossil fuels used to power appliances.

One incredibly important reason to care about the ENERGY STAR federal tax credit for energy-efficient green products, in particular, is its expiration date: December 31, 2010.

This federal tax credit is a comprehensive one and covers a number of products, some of which are carried by Green Depot, like the GeoSpring Hybrid Water Heater or the Solatube Solar Star Attic Fan.  So many products are eligible for tax credits through 2010 – including biomass stoves, central A/C, electric heat pumps, furnaces and boilers, main air circulating fans; insulation materials or heat control systems; metal and asphalt roofing; water heaters, electric heat pumps; exterior windows, doors, and skylights.  The federal tax credit can cover up to 30% of the cost of these products, up to $1,500.

State rebates and incentives exist too, and some can cover the additional costs of installing the above products.  Some incentives go even further than federal incentives – for example, New York State includes a tax break of up to $2,000,000 (million!) for green building.

There are so many rebates and tax breaks that apply to so many different products that everyone can benefit from – proving that rebates are something anyone can and should care about!

There are numerous resources available for the homeowner looking to upgrade their homes and appliances to green products:

DSIRE to see which rebates and tax breaks are available federally and in your home state.

U.S. DoE Energy Savers Program with information on incentives.

ENERGY STAR’s compendium of rebate-eligible products.

by flickr user caveman_92223

When we think of where our energy comes from, we more often than not envision the billowing smokestacks of a coal plant.  It’s true that coal is a major source of energy for most Americans, accounting for over 50% of our energy production according to the Department of Energy, but it’s also important to remember that it is not our only source of energy.

Take, for instance, the massive proliferation of wind power over the last few years.  In 2008, new wind projects accounted for 42% of new power-producing capacity for the United States, and an additional 10,000MW of new capacity were brought online in 2009.  According to the American Wind Energy Association, this sets the U.S. on track to produce 20% of our electricity from wind by 2030,

Wind power accounts for nearly 2% of the electricity produced in the United States, but represents a power source that is considered more-or-less environmentally-friendly.  Wind turbines, after production and installation, do not necessitate the use of fossil fuels to produce energy.  The attributable benefits are substantial – the wind power fleet in the U.S. avoids an estimated 62 million tons of carbon dioxide annually – an equivalent of taking 10.5 millions cars off the road and conserves 20 billion gallons of water annually otherwise slated for cooling or steam production in fossil-fuel and nuclear power plants.

Compared to the burning of fossil fuels for energy, wind power is indeed an environmentally-option, but is beset by some other challenges.  One of the foremost is local opposition to the aesthetic appearance of a wind farm on agricultural or ocean landscapes (notoriously, construction on the Cape Wind Project was delayed for years for this reason).  There have been accusations that wind farms disrupt migratory bird patterns, and that windmills produce low-level vibrations and noise (a claim which has yet to be scientifically verified).

Still, the future of wind looks bright – the DoE’s Wind and Water Power Program notes the proliferation of small scale and distributed wind turbines, large-scale offshore wind projects, and 20% targets for wind production by 2030.  Weaning ourselves off of fossil-fuel consumption can only mean good things for the state of the planet.

As we try to travel in greener directions through the wild, wild west of the consumer market, there are plenty of markers along the way to guide us–in the form of eco-labels, those little green symbols printed and/or stuck on nearly everything you can buy these days. There are symbols indicating that a product is organic, chlorine-free or grown upside down without soil; that it was made by people paid a fair wage or by chickens allowed to go for walks in the sun. If there’s an environmental issue worth considering, there’s an eco-label related to it—which on one hand is fantastic, but on the other… Well, it gets to be a bit much. After a while, all the symbols seem to fade into a solicitous green haze with about as much meaning as the words “As seen on TV!” on the box of the latest trendy gadget. And what’s worse, some of the labels don’t even mean what they appear to. Who would guess that their “free range” chicken might have never even seen the open sky? And others don’t mean very much at all, like organic labels on fruits and vegetables that aren’t normally grown with pesticides to begin with.

But we’re not likely to see any fewer eco-labels anytime soon–we’ll probably only see more, and some of them are genuinely useful indicators of qualities you might actually care about. So with that in mind, here’s a brief run-down of a few of the most commonly seen eco-labels and what they mean, then a list of places where you can learn more about these online and look up the rest of them, too.

EnergyStar is probably the most often-seen eco-label. EnergyStar is a joint program of the EPA (U.S. Environmental Protection Agency) and the U.S. Department of Energy, and it awards the EnergyStar label to household products, homes and nonresidential buildings that meet its energy efficiency requirements. Its standards are lower than those required for LEED certification, but it’s a decent start.

LEED (Leadership in Energy and Environmental Design) is a program run by the U.S. Green Building Council, a nonprofit organization with no government affiliation. LEED provides third-party verification that a building project followed green building procedures, meets energy efficient performance standards, and is a health place to live or work. The main criteria for evaluation are sustainable site development, water savings, energy efficiency, the use of sustainable materials (e.g. low-VOC paint, green insulation) , and a healthy indoor environment. The program is based on a system that awards a silver, gold, or platinum certification level, based on the number of points a project was able to win by addressing the various criteria. Certification is entirely voluntary.

USDA Organic This label indicates that the product meets the National Organic Program of the U.S. Department of Agriculture’s standards for using the word “organic” in its labeling. These standards vary for the different products that are eligible for the label, which include not only food but personal care products as well. But most require the absence of synthetic fertilizers, conventional pesticides, antibiotics, growth hormones and sewage sludge in the production process. You can find a table outlining the different requirements for different products here.

Fair Trade This symbol indicates that the product has been certified by TransFair USA, which is the only U.S. member of FLO (Fairtrade Labeling Organizations International, the Germany-based umbrella organization for a group of 20 international fair trade certifying nonprofits). Fair Trade Certification standards help farmers and farm workers to lift themselves out of poverty by investing in their farms and communities, protecting the environment, and helping them developing the business skills necessary to compete in the global marketplace. The label signifies that the product was grown by small-scale farmers who are democratically organized, either in a co-ops or unions; that the buyer paid up to 60% of the cost of the raw materials in advance, that a fair wage was paid and no child labor was used in production, that none of the 10 worst pesticides were used in the growing process, and that the buyer paid additional premiums to go toward services to support and develop the farm community.

FSC The FSC label indicates, essentially, that a wood product was grown in a forest that is being managed responsibly and sustainably. The FSC (Forest Stewardship Council), certifies forest managers and manufacturers of wood products that it determines are managing forests and using forest products responsibly and sustainably. Among their major concerns are not allowing logging practices to destroy forests, protecting the habitats of endangered wildlife, and making sure the profits from commercial forest endeavors are shared fairly with communities living in the forests. The FSC is not affiliated with any government, is a nonprofit organization, and certification is entirely voluntary.

For more info on these and literally hundreds more eco-labels, see these links:

Consumer Reports’ Greener Choices Eco-Label page

The Global Ecolabel Index

Inhabititat’s Eco Labels 101

Top image courtesy of Shutterstock

In our series on passive houses this week, we’ve discussed the merits of saving energy by using condensing driers, of tightly insulating homes to achieve super-efficient energy standards, and we’ve talked about the general merits of building a passive house.  One of the things we’re also interested in are examples of passive buildings – of homes built in the U.S., as well as passive homes, schools, and office buildings built around the world.

As the New York Times reports, there are currently 25,000 passive house-certified buildings in Europe.  In the U.S., however, there are only 13.  While passive design in Europe is well-established – tested by time, certainly (the first homes were built in 1990) – the standard has taken longer to catch on the in United States.  Materials rated efficient enough for the standard are more difficult to find here, and designers who are certified in, and understand well, the criteria are few and far between.

This is not to say, however, that people in the United States haven’t risen to meet the challenge of passive house construction.  Our mention of the Habitat for Humanity home proves as much.  The Times article on the Landau home does, as well.

image courtest of root design build

One of the first homes in the U.S. built to the standard was Shift House, in Portland, Oregon.  As the Williamette Week wrote last year, the Shift House was designed not only to meet the stringent standards of Passive House certification, but was also deliberately designed to be highly aesthetically-appealing.   Another unique aspect of the Shift House was its use of an 8-inch-thick structural insulated panel, or SIP, that acts as the primary pressure envelope for the house.  Even other passive houses in the U.S. don’t utilize this technology or this emphasis on design – proving that even for architects and contractors, there are a variety of materials and techniques available to build passive homes.  Green Depot offers some of those materials in the green building materials department.

While in the U.S. we might only have 13 existing structures, in 1997 there were only ten passive houses in existence in Germany, where the standard was first invented.  The current record of 25,000 European passive buildings then represents an enormous and astonishing leap forward.  But in Europe, it is not only residential houses that have been built to the passive standard.

neue burse residential hall. image courtesy passiv haus institut.

Case in point: the Neue Burse residence hall, or dormitory, located at the University of Wuppertal in Wuppertal, Germany.  The building, which was originally constructed in 1977, was deemed to be a massive energy sink that required significant amounts of energy to keep in operation.  It was decided to refurbish and retrofit the building to passive standards.  Construction was completed in 2003, and represents the largest residential building in Germany to comply with the passive house standard.

social housing in kassel marbachshoehe. image courtesy of passiv haus institut.

In Kassel-Marbachshohe, city officials undertook the ambitious project of ensuring that their next public housing development meet the passive standard.  While building specific-user residential homes on empty lots provides the architect with a significant degree of free in designing a home for energy efficiency, designing in tight urban spaces offers new challenges.  Despite this, however, 40 residential units in a multi-story complex were constructed using public funds, and the building was able to meet an 82% increase in energy efficiency over conventional construction (page in German).

office building sportplatzweg. image courtesy hermann-kaufmann architects.

In 1999, the German architecture firm Hermann-Kaufmann designed an architectural office space to passive standards (page in German).  As described on their project page, the building experiments with new materials: the staircase is covered with fabric, and the base of the building is covered with painted oriented strand board (OSB).  The Office Building Sportplatzweg, situated on an open expanse, is a brilliant example of how architectural design can be both ecologically-sound and blend beautifully with the surrounding landscape.

While these buildings do provide valuable examples of the tried-and-true design philosophy of passive house criteria, it is still somewhat disheartening that only thirteen examples exist in the United States.  Consider, though, that presently 160 architects have been trained as passive-house designers, and that that number is expected to rise to 300 by the end of the year, and the picture looks less bleak.

The more awareness that is made of this certification system, and the more the government begins providing tax rebate incentives for passive house construction (in the same way the government already does for LEED or Energy Star construction), the brighter the future of truly energy-efficient passive buildings in the U.S. looks.

Visit Green Depot to get more ideas on building materials and green products to make your home more environmentally-friendly.

courtesy Passive House Institute U.S.

Earlier this week we wrote about Habitat for Humanity’s first passive house being built in Vermont.  While many readers are perhaps familiar with some of the building standards for LEED or Energy Star certification, we’re also interested in the exact criteria that go into building a passive home.

Passive house certification is certainly the highest energy standard for home building.  As the New York Times notes, a LEED-certified home can be certified as such with only a 15% improvement in efficiency over conventional construction; passive homes are capable of achieving 90% efficiency over conventional homes, and some are even able to return electricity into the grid, netting a negative energy consumption rate.

These homes are well-insulated (nearly air-tight) and heated by passive solar energy – like a greenhouse – and internal energy gains from human body heat or, for example, the heating of a tea kettle.  Achieving this level of efficiency requires exacting design, including the very specific angle of construction towards the sun.  Achieving passive house certification from the Passive House Institute U.S.A. requires a very rigorous evaluation of the home’s energy consumption and insulation.  For a home to be passive, it must be determined to have:

1. a maximum annual heating requirement less than or equal to 15 kWh/(m²a)

2. a pressurization test result with a maximum of 0.6 h^-1

3. an entire specific primary energy demand less than or equal to 120 kWh/(m²a) including domestic energy consumption.

What this means is that the house cannot require heating or cooling demands beyond the specific thresholds detailed above.  Accomplishing this requires super-tight insulation of the home.  To be more specific, the pressure envelope of the home cannot exceed a loss of pressure of 0.6 air changes per hour (the number of times per hour that a room’s total air volume is exchanged with fresh air at 50 pascals), measured by blower-door test – only a minimal amount of air (heated air in the winter) is allowed to escape the home.  This level of insulating efficiency reduces the heating requirement to below the aforementioned threshold, and reduces the level of electrical consumption needed to cool or heat the home.

To read more about passive house certification, you can read Passive House Institute U.S.’s performance characteristics, or read Passiv Haus Insititut’s residential criteria (PDF).

To read more about green insulation options here in the U.S., as well as green products, low-VOC paints, and other eco friendly building materials, you can always visit Green Depot’s homepage.