Construction material varies with types of construction, geographical location, amenities desired, and other factors. Materials typically include concrete, wood, steel, stone, glass, drywall, brick, landscaping, etc.
Building Components and Life Expectancy
In February 2007, the National Association of Home Builders/Bank of America Home Equity issued a report, Study of Life Expectancy of Home Components.[i] The following describes the U.S. Housing Stock in 2005:
The 2005 American Housing Survey by the U.S. Census Bureau shows that there are more than 124 million homes in the housing stock, with a median age of 32 years. About one-third of the housing stock was built in 1960 or earlier. About 10 percent was built in the 1960s, and another 20 percent was built in the 1970s. Of the remainder, 13 percent was built in the 1980s, another 13 percent was built in the 1990s, and 8 percent in the first years of the 21st century.
Of the total stock of 124.3 million housing units, about 109 million are occupied housing units, 11.6 million are vacant and about 4 million are seasonal. Two-thirds of all units in the nation’s housing stock are single-family detached or attached, 8 percent are in buildings with 2 to 4 units, and about 17 percent are in buildings with 5 or more units. The remaining 7 percent of the stock is in HUD-code homes.
About 18 percent of the occupied housing stock is in the Northeast, 23 percent is in the Midwest, 37 percent is in the South, and 21 percent is in the West.
Here are just a few of the study’s findings:
- Concrete and Masonry
Masonry is one of the most durable components of a home. Chimneys, fireplaces, and brick veneers can last a lifetime, and brick walls have an average life expectancy of more than 100 years.
- Engineered Lumber
Floor and roof trusses and laminated strand lumber are expected to last a lifetime, and engineered trim is expected to last 30 years.
- Footings and Foundations
Poured as well as concrete block footings and foundations last a lifetime, assuming they were properly built. Termite proofing of foundations will last about 12 years if the chemical barriers put in place during construction are left intact. Waterproofing and bituminous coating lasts 10 years, but if it cracks it is immediately damaged. Concrete or cast iron waste pipes are expected to last 100 years or more.
- Framing and Other Structural Systems
Framing and structural systems have extended longevities: poured-concrete systems, timber frame houses, and structural insulated panels will all last a lifetime. Wall panels and roof and floor trusses will similarly last a lifetime. Softwood, hardboard, and plywood last an average of 30 years, while OSB and particleboard are expected to function properly for 60 years.
- Insulation and Infiltration Barriers
As long as they are not punctured, cut, or burned, and are kept dry and away from UV rays, the cellulose, fiberglass, and foam used in insulation materials will last a lifetime. This is true whether the insulation was applied as loose fill, house wrap, or batts/rolls.
The life of a roof depends on local weather conditions, proper building and design, material quality, and adequate maintenance. Slate, copper, and clay/concrete roofs have the longest life expectancy – over 50 years. Roofs made of asphalt shingles last for about 20 years while roofs made of fiber cement shingles have a life expectancy of about 25 years, and roofs made of wood shakes can be expected to last for about 30 years.
[i] National Association of Home Builders/Bank of America Home Equity, Study of Life Expectancy of Home Components, Prepared by the Economics Group of NAHB, February 2007, http://www.nahb.org/page.aspx/generic/sectionID=152.