How to Determine If You Need an Engineer for a Retaining Wall Design

How to Determine If You Need an Engineer for a Retaining Wall Design

To determine if an engineering plan is needed for your retaining wall project, take the time to evaluate the following:

How tall is your wall?

Most municipalities require a building permit and a design from a Licensed Engineer if your wall is taller than 4 feet high (measured from the bottom of the first block to the top of the last block).

Will your retaining wall be terraced?

A terraced wall can be tricky to build. There are a set of rules to follow. A general rule of thumb- the back terraced wall must be set back from the front wall twice the front walls height i.e., for a 3 foot front wall, back wall must be back 6 feet. If the back wall is inside of that zone, then the wall is considered as one wall, and the 4 foot building permit and engineering is required. The back wall must also be shorter in height than the front wall. Contact a Licensed Engineer for his advice and a design.

Will you be parking cars, motor homes, trailers or other vehicles on the top?

If the chance exists that you might be parking a heavy object on top of the wall, it is a good idea that you consult with a Licensed Engineer and get his recommendations- vehicle-parking, slabs-snow loads place a large strain on a retaining wall. Wall problems may not show up until the wet season begins, so consulting with a Licensed Engineer will help put a plan together to reduce your chance of problems.

Will there be a slope at the top of the retaining wall?

If there is a slope at the top of the wall (California’s maximum is 2:1), then you will need the assistance of a Licensed Engineer. They will evaluate the surcharge that will be placed on the retaining wall, and verify if a design is necessary.

While this list is not 100% complete, it is meant to help you in deciding whether or not you need to consult with a Licensed Engineer. When in doubt, consult a Licensed Engineer for advice. Doing so may prevent a costly mistake.