How To Look At A House

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Why are older houses, specifically ones built before 1940, more difficult to evaluate for a home inspector?

Wednesday, August 21, 2019

There was a dramatic change in house construction between the era before World War 2 and after it. Previous to the war, materials and details of construction varied, sometimes dramatically, between regions of the country. A home was built of mostly local materials by craftsmen that used regional methods and materials, and had minimal building code standards to meet, and a home in Ohio was very different from one built in Georgia. Brick and lumber, for example, were sourced nearby, and some materials were only available in one part of the country.

    But post-war manufacturing and transportation advances meant that building materials were made for a national market, and building codes became more specific and standardized across the nation. By the 1960s, new homes at opposite end of the country looked amazing similar, which makes it easier for a home inspector to evaluate.

    So old homes often have unique details that take a while to figure out, plus multiple layers of improvements and repairs. Plumbing and electrical systems are rarely completely replaced, so part of a system might be original, while another part is fairly new. 

    A pre-1940 house becomes a jigsaw puzzle to solve. Since the average homeowner in America moves every seven years, an 80-year-old house probably accumulated at least 10 owners; and the new ones have no idea what modifications were made by the earlier owners that are buried in the walls, in the attic, or under the floor. 

    Fortunately, the problems that occur in old houses are, in general, the result of fairly simple mechanisms. An inspector can focus on the effects of time, temperature, and moisture to determine the cause of most old-house defects. Other things, like understanding long-abandoned construction techniques, such as plaster over wood lath, may require some research. And, of course, experience in inspecting old houses is always helpful.

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Here’s links to a collection of our other blog posts about OLDER AND HISTORIC HOUSES: 

• What is a chert house?

• What is "Ocala" block? 

• What are the most common plumbing problems with older houses? 

• Is this old home a Sears Catalog house? 

• What are the most common problems with older houses? 

• Why is an old fuse box/panel an insurance problem for homebuyers? 

• Why is there no bathroom electric receptacle in this old house? 

• Does a home inspector expect the  electrical system of an older house to meet current code standards? 

   Visit our OLDER AND HISTORIC HOUSES page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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