Many home buyers are scared about foundation problems because foundation repairs can be costly!
Foundation inspections are recommended by your general home inspector if they notice the floors inside a house are uneven, if the house has cracks in the walls, or they can see cracks in the foundation when they crawl, or spalling, or deterioration of the foundation. They test the sturdiness of the foundation by banging it with a hammer, if it starts to crumble they know that its lost its structural integrity.
if the door jambs and windows are crooked.
or if a retaining wall that looks like it is about to fall over
The Physical Inspector will be crawling underneath the house aswell, and if they are good, they will crawl the entire perimeter of the foundation to inspect the stem wall for cracks.
To repair a foundation crack like the one above is a $1,200 job. The repair would put some sort of concrete apoxy to fill the crack and secure it with a metal strap
In California there are a number of reasons a foundation might be having problems. The number one enemy of foundations is water, because they are made of concrete and steel rebar, both of which deteriorate when exposed to water for prolong period. When the foundation wears away from water eroding it, this is a condition know as “SPALLING”
The repair for Spalling is to pour new concrete to rebuild the wall that has deteriorated and fix any drainage problems.
Houses that were built before the 1940’s sometimes were built on uncompacted fill. This is not good, because soil tends to expand and contract at different times of the year when moisture levels changes, which can cause damage. The type of soil that is underneath the foundation also plays a key role. Clay soils tend to expand and contract the most.
Houses in Los Angeles built prior to 1940 have post and pier foundations.
The Piers in these foundations were laid out in an uniform grid that had no consideration give to the location of the load bearing walls. As a result, these older house tend to have uneven floors in places.
Past earthquakes could have caused damage in the past that was never known or fixed. Seismic retrofits can prevent future damage from occurring. If the property has had a seismic retrofit already, the foundation inspector will double check it to make sure it was done correctly and is in good shape.
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