Lifecycle Design
A couple in Lindenhurst, IL, ask:
We are beginning to plan our new home on vacant land we recently purchased. After reviewing hundreds of house plans, it seems the layouts we like are all too large for our budget. We have no idea how energy efficient they are, and don't want to get in over our head with monthly costs. Is there some sort of rating system for homes, like the EPA “Miles per gallon” ratings on new cars?
While I don't know of any energy rating system for homes, many building departments are now requiring an energy audit be completed by the architect prior to the issuance of permits, to be sure that the home meets minimum conservation standards. All materials that make up the building envelope have “R” values; a measure of the it's ability to contain (or keep out) heat, so it is possible to determine a home's heat retaining ability. And most appliances come with power usage information that gives you at least some comparison prior to purchasing.
Your question raises a good point about the “Lifecycle Costs” associated with buildings. When designing a house, most builders and homeowners focus on the immediate task at hand; satisfying the requirements of budget, curb appeal, interior flow, room sizes and proximities. But well-designed homes have to deliver much more: they need to provide efficiency and value on a long term basis. The home is often the single largest investment people make, so architects and contractors, whether they admit it or not, have become “asset managers,” similar to stock brokers, investment counselors, and accountants. They need to maximize the Lifecycle Design of the buildings they create.
Condominium Associations and Commercial Building Managers are well aware of the ongoing costs of maintenance, because they have to prepare and/or update an engineering study to as to budget for the appropriate amount of monthly assessments or cash reserves they need to have money in the bank when building systems age and fail. But individual homeowners don't have that knowledge readily available while they plan their home, leading to building's that become needlessly inefficient.
Lowering the ongoing cost of a building can occur by paying attention to these three categories:
1. Spatial Efficiency
With a house with a poor layout, it's tough to catch up on cost savings later. If it's larger than it need to be, with longer than necessary corridors. If there are odd room shapes that can't be properly furnished or utilized. If there are single-sided utility rooms that don't maximize the storage potential of the area. If the doors or windows are in the wrong location of a room so to prohibit efficient furnishing. All these lead to a wasteful plan that not only costs more initially, but costs more annually too.
There are some well-designed 2,000 square foot homes that have as much usable living space as a poorly designed 3,000 square foot one. Homes that carry extra space are more costly to heat and cool, to furnish, to maintain, and to insure. Other than being able to boast about the homes size to friends or potential buyer's, there is not much value in waste footage that a homeowner can derive.
When a building's overall shape is long and thin, more materials have to be used to enclose the same amount of usable space of a building that is more cube-like. A perfect sphere, in theory, contains the least amount of “skin” surface relative to the most interior area. Nature knows this, and that's why bubbles aren't square! This led futurist Buckminister Fuller's creation of the Geodesic Dome, the premise of which was to minimize exterior materials while maximizing interior space. While a sphere presents other building difficulties, it pays to keep a building's shape as close as possible to this pure geometric form.
A poor plan that wastes 500 square feet can cost $50,000 to $100,000 too much in today's dollars. That translates to $400 to $800 per month being paid for virtually no benefit, not to mention the loss of the initial expenditure when it comes to resale.
Energy Efficiency
It pays to design a home that naturally heats and cools as much as possible, rather than relying on mechanical systems for all the comfort. 40 years ago, the cost of “Active” alternative energy systems such as solar collectors or wind generators tended to be more costly than the savings they yielded. Although the costs are coming down and are now becoming more economically practical, “Passive” energy design, the kind that relies on the creativity of the designer rather than costly mechanical solutions, always pays.
Insulate walls and roofs to the optimum recommended for the area. Pay more attention to the ceiling, as 60% of the building's heat loss occurs through the roof. Seal all shim spaces, foundation sills, and other cracks that can steal energy. Don't forget to ventilate trapped air spaces where necessary, to prevent moisture accumulation in ceilings and walls that can diminish the effectiveness of the insulation.
Maximize south and southeast exposures for passive heat gain in the winter. Protect those south (and west) openings with overhangs, awnings, or brise-soleils to keep the sun's heat out in the summer. Minimize north and west facing windows to keep in heat and keep out the dominant northwesterly winter winds. Where possible, place garages and utilities on the northwest side of the building. Flow ventilation through the house, not only with opposing windows that encourage breezes, but with vertical airflow that allows heated air to rise and exit, while cooler air is drawn in from low openings. Retain or plant deciduous trees on the south to let the sun through in winter, but keep it out in the summer. And the more trees the better; each one can have an acre of leaf surface that vents moisture and can keep the air around the house 10 degrees cooler in the summer.
The closer a building's shape is to a sphere or cube, the more energy efficient the mass is. Cost efficient buildings are shaped the opposite of a car radiator; the fin-coils of a radiator are designed to MAXIMIZE the surface area of the metal so to cool the liquid inside, while a tight building tries to MINIMIZE the surface area while enclosing the most amount of interior space.
A well designed, energy efficient home can cost little or nothing more to build, but can save hundreds (even thousands for very large homes) of dollars a month.
Material Selection
The majority of the cost of construction of a building is labor, not materials. On average, about 2/3 of a building's costs is labor, with the other 1/3 materials. That means it often pays to increase the quality and durability of a material, often without any change in the installation price. Think about each material choice, not only for the initial dollar you are spending, but the annual amount needed to maintain, repair, and replace things.
Wood windows can look rich and warm, but require constant restaining and repainting, not to mention the inevitable warping. Consider vinyl's and clad assemblies that cost far less initially and are far lower in maintenance. Masonry and composite sidings require little or no upkeep, compared to real wood or synthetic stuccoes. Aluminum fascias and soffits cost far less to maintain than wood.
A standard lightweight shingle can last about 15 years. Heavyweight shingles, while costing more initially, can look richer and come with 25, 30, even 50 year warranties. For about 1-1/2 to 2 times the initial cost, the roof can last 3 times as long and require far less maintenance; a cost savings in the long run. Vinyl wall coverings cost more than basic painting, but can last 30 years or longer without replacement or upkeep; a fact well known to commercial designers. And “You get what you pay for” when it comes to hot water heaters, furnaces, appliances, garage door openers, and other items that can either fail after a few years, or last 30.
Remember, every design decision you make initially can either save money for, or cost the future occupants dearly over the life of the house.
This professional opinion is from Kerry Levin, the award-winning Principal of Levin Associates Architects, a full service design-build firm with offices in Illinois and Wisconsin. He has specialized in residential and commercial construction, as well as brokerage and development, for over 25 years, and can be reached at 847-297-1121, ext. 100, or emailed at Klevin@Levin4in1.com with questions or comments.
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