The new American Dream: 100K(+ 20) | Starter Home


Zero-Emissions Home, UK by nataliemikosz
September 3, 2008, 3:55 pm
Filed under: precedents | Tags: , ,

The Kingspan Off-Site’s Lighthouse design is an example of a zero-emissions home design in the UK that was unveiled in 2007.  It utilizes (1) a wind catcher for summer ventilation, (2) photovoltaic panels for hot water and electricity, (3) a high level of wall insulation, and (4) a biomass boiler.  The house would cost about 40% more than an average house of the same size, but will save tremendously in operating costs, which will over-time cancel out the initial pricetag. 

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About: Green Roofs by nataliemikosz
September 3, 2008, 3:40 pm
Filed under: Material/Building Systems | Tags: , ,

Intensive green roof on the Chicago City Hall building

A green roof is a roof of a building that it partially or completely covered by vegetation. They are divided into two categories: intensive or extensive, based on their depth of planting medium. An intensive green roof is your typical roof garden which requires a generous depth of soil in order to grow large plants. They are considered ‘intensive’ because they are labour-intensive, requiring irrigation, feeding and other maintenance. On the contrary, an extensive green roof can be established on a relatively thin layer of soil, and is typically self-sustaining.

Green Roof Diagram

Green Roof Diagram

The benefits of using a green roof system include but are not limited to reducing the heating and cooling loads for the building, reducing the heat island effect, filtering pollutants out of the air and rain water, providing better insulation for sound, and increasing the roof’s lifespan. The primary disadvantages are the increased roof load, which increases the structural demands of the building; and the increased cost in comparason to a standard shingled roof.

In addition to deciding between an intensive or extensive green roof, there is also the choice between using a typical system, where the planting media is installed directly over a membrane and various other layers; or a modular system where the plants and soil sit in trays or pots, which are then placed on the roof. It is argued that a modular system is not a true green roof system, since it is not applied directly to the roof like that of a standard system.

Your standard extensive green roof can cost as low as $8/sf, whereas your standard modular system typically costs atleast $15/sf or more if you want fancy plants.

Sources: http://www.greenroofs.com/ http://en.wikipedia.org/wiki/Green_roof



About: Geothermal by nataliemikosz
September 3, 2008, 3:40 pm
Filed under: Technology | Tags: ,

Geothermal heating has frequently been used to refer to the heating and cooling that can be achieved through the use of a geothermal heat pump. This technique is generally for residential use. It involves a refrigerant liquid being pumped through pipes in the ground, heating the liquid. This liquid then is brought back into the house, and the heat exchanged. The same technique is used to cool the house. Geothermal heat pumps take advantage of the natural constant temperature of the earth. During winter when the ground temperature is warmer than the air above it, geothermal heat pumps use the earth’s soil (or groundwater) to recover the earth’s heat. In contrast, an air-source heat pump will remove heat from the cold outside air and thus requires more energy. In the summer months, geothermal heat pumps deliver heat to the same relatively cool soil (or groundwater) rather than delivering it to the hot outside air. As a result, the heat is pumped over a smaller temperature difference with a geothermal heat pump and this leads to higher efficiency and lower energy use. (http://en.wikipedia.org/wiki/Geothermal_heating)

A diagram of the different types of a residential geothermal system

A diagram of the different types of a residential geothermal system

As with most innovative sustainable technologies, the initial cost of a geothermal system can be rather high (on average $20,000 for a 2,000 square foot house), but it will pay for itself after some time. If you spend $2000 annually to heat your 2,000 square foot house, then your system will be paid off after 10 years, and you will no longer need to pay to heat or cool your house. Another advantage of utilizing a geothermal system versus wind or solar power is the constant heat exchange; while solar and wind power are only beneficial if the proper conditions are present.



About: Solar Water Heaters by nataliemikosz
September 3, 2008, 3:39 pm
Filed under: Technology | Tags: ,

Solar hot water is water heated by the use of solar energy. Solar heating systems are generally composed of solar thermal collectors, a fluid system to move the heat from the collector to its point of usage. The system may use electricity for pumping the fluid, and have a reservoir or tank for heat storage and subsequent use. The systems may be used to heat water for a wide variety of uses, including home, business and industrial uses. (http://en.wikipedia.org/wiki/Solar_hot_water_heater)

In many climates, a solar heating system can provide up to 85% of domestic hot water energy. Typically, a solar heating system will supplement a standard hot water heating system, or ‘point of use’ system, which act as back-ups. Solar heating systems are becoming more widely used, and therefore, are lowering in their initial cost.

Solar Direct has a system consisting of “skylight” looking flat-plate collectors and a typical hot water tank that runs roughly $2500 for a project of our size.



Eco-nomics by nataliemikosz
September 3, 2008, 3:39 pm
Filed under: Social / Cultural Issue | Tags: , ,

The United States is ranked one of the top five world leaders in air pollution emissions.  Pollution is the introduction of contaminants into an environment that cause instability, disorder, harm or discomfort to the physical systems or living organisms therein.  (http://en.wikipedia.org/wiki/Pollution)  

Motor vehicle emissions as well as carbon emissions from running our own homes are among the top leading contributors of air pollution, which we have direct control over.  On average, a single family home has a carbon footprint of 12.2 TONS of carbon per year.  Not only does this create an obsene amount of pollution, it also comes with a price tag of $2,451/year on average to operate this single family home.  (http://www.epa.gov/climatechange/emissions/ind_calculator.html)  Just imagine how having a zero-emissions (or even a relatively sustainable) home could save the earth and your wallet.



LiveRoof: A Modular Green Roof System by nataliemikosz
September 3, 2008, 3:39 pm
Filed under: Technology | Tags: , ,
An example of one LiveRoof tray

An example of one LiveRoof tray

This company specializes in modular “tray” green roof systems, except that they boast an “invisible” tray, which gives the modular system a monolitic look. They’re based out of Michigan, so for those of you who are siting your projects in the Midwest, this may be an option for you. I got an estimate of $12,160 for a 1000 square foot roof, which is pretty heafty, but you save on installation. This price doesn’t beat out the overall price of a typical extensive green roof system, but your paying for the convenience. It’s much easier to install this type of system as well as replace problem areas and/or access a damaged spot in the membrane.

Check out their site: http://www.liveroof.com/



About: SIPs by nataliemikosz
September 3, 2008, 3:37 pm
Filed under: Material/Building Systems | Tags: , ,

Structural Insulated Panels, or SIPs, are a composite building material. They consist of a sandwich of two layers of structural board with an insulating layer of foam in between. The board is usually oriented strand board (OSB) and the foam either expanded polystyrene foam (EPS), extruded polystyrene foam (XPS) or polyeurethane foam.

SIPs share the same structural properties as an I-beam or I-column. The rigid insulation core of the SIP performs as a web, while the OSB sheathing exhibits the same properties as the flanges. SIPs replace several components of conventional building such as studs and joists, insulation, vapor barrier and air barrier. As such they can be used for many different applications such as exterior wall, roof, floor and foundation systems.

The use of SIPs brings many benefits and some drawbacks when compared to a conventional framed building. A well built home using SIPs will have a tighter building envelope and the walls will have a higher insulative value, which leads to fewer drafts and a decrease in operating costs for maintaining a comfortable interior environment for the occupants. Also, due to the standardized and all-in-one nature of SIPs construction time can be reduced over building a frame home as well as requiring fewer trades for system integration. The panels can be used as floor, wall, and roof, with the use of the panels as floors being of particular benefit when used above an uninsulated space below.

An OSB skinned system structurally outperforms conventional stick framed construction in some cases; primarily in axial load strength. SIPs maintain similar versatility to stick framed houses when incorporating custom designs. Also, since SIPs work as framing, insulation, and exterior sheathing, and can come precut from the factory for the specific job, the exterior building envelope can be built quite quickly.

The EPS insulation is a closed cell insulation as compared to fiberglass insulation which is an open cell insulation. Both insulations’ R-values are tested in a laboratory under steady state conditions where there is no air infiltration. When a SIP is installed as a wall, foundation, floor or roof system, the EPS is installed in a steady state environment, whereas fiberglass insulations are installed in a non-steady state environment because these wall, foundation, floor and roof systems have to be vented to remove moisture. Many research studies show that the R-values of fiberglass insulation decrease as the temperature differential of indoor and outdoor temperatures increase resulting in higher energy costs to the homeowner. EPS foam is a non-toxic hydrocarbon. Burning it results only in water vapor, carbon dioxide and trace levels of ash, similar to paper. (http://en.wikipedia.org/wiki/Structural_insulated_panel)

R-Control SIPs have a production and sales facility in Waukegan, IL; which may appeal to anyone who will be siting their project in the Chicagoland area, since the SIPs are prefabricated and require shipping. I am currently awaiting pricing information.