The National Association of Home Builders (NAHB) in partnership
with Bank of America Home Equity recently completed a study that should be of
interest to home owners and home buyers, especially those that are buying or living
in homes that have been around for a while.
The Study of Life Expectancy of Housing Components is the result of
a telephone survey conducted by NAHB of manufacturers, trade
associations, researchers, and others to gather information about how long various
components of a house should be expected to last.
Expectations are, of course, only that. They are not hard and fast guarantees
of durability or the absence of same. Maintenance is a big factor in determining
how long something is going to last and changing technology, styles, or other
consumer preferences can impact how long consumers are willing to keep a component
if they feel it is outmoded or can afford to replace it.
According to the 2005 U.S. Census Bureau Housing Survey, there are 124.3
million homes in the U.S. housing inventory with a median age
of 32 years. About one-third of the homes were built in 1960 or earlier, 10
percent were built in the decade of the 1960's, 20 percent in the 1970s,
13 percent in the 1990's and 13 percent in the first five years of the
Approximately 11.6 million of the total houses are vacant and another 4 million
are used seasonally. While two-thirds of units are single family residences
and 8 percent are in two-to-four-family buildings.
About 18 percent of the occupied housing is in the Northeast, 23 percent is
in the Midwest, 37 percent in the South, and 21 percent is located in the West.
Data from the survey is reported several ways. Some components are given a
range of years (aluminum windows are expected to last between 15 and 20 years
while wooden windows should last upwards of 30 years.) Others are said to be
good for a lifetime or for 100 plus years. There was no explanation for the
difference between the latter two descriptors but perhaps the selection was
left up to the respondents.
The executive summary is a quick read with a lot of information on life expectancy
but the back-up tables are more comprehensive with a few explanatory comments
or suggestions for maintenance The survey covers an impressive number
of building parts; structural components (engineered lumber, masonry, brick
veneers, footings, foundations, and framing;) appliances, cabinets, doors made
of a number of materials; heating, ventilation, and air conditioning components;
insulation; roofing; even components related to the site and to landscaping
such as sprinklers, driveways, tennis courts, and swimming pools.
The authors of the survey are careful to disclaim the study findings as being
more than general guidance and that is good advice. Dishwashers, for example,
are expected to last about 9 years which means that the 44 year old Kitchen
Aid in my kitchen is, as I suspected, continuing to run solely out of spite.
Vinyl floors are supposed to last 50 years which begs the question of what they
must look like even half-way into their expected life span. Still, most of the
information is relevant and helpful, especially where figures are given for
different types of the same component ("natural wood floorings have a
life expectance of 100+ years while marble, slate, and granite can fail earlier
due to lack of maintenance.")
While logic may suggest that the older sub-sample of homes mentioned above
would have had many original components replaced that is probably not true where
those components continue to function. Therefore, someone looking at a house
built in 1975 is probably looking at a lot of 32 year-old parts so this study
can be a useful source of information to guide purchases and
remodeling decisions. NAHB may not keep this on its website for long so it would
be well to print it off and keep it for future reference. The entire report
is contained in a 19 page PDF file and is available at www.nahb.org.