Much of the evidence supporting the benefits of retrofitting was developed as a result of the devastating earthquakes in California, in the late 1980s to the mid-1990s.
Several studies were conducted. These studies showed that the proper use of foundation bolting and other ‘retrofit’ measures, can aid in residential structures surviving a major earthquake and reducinge the extent of damage.
Earthquakes damage buildings in two ways; by shaking or heaving the ground. Shaking weakens a houses frame and heaving the ground can actually lift the building from its foundation.
The City of Seattle has come up with a house retrofitting program for reducing the effects of an earthquake. This retrofitting increases the structural integrity of the house. Plans and suggestions can be viewed at the DPD Emergency Management site.
Alpha Builder, based on the City of Seattle’s recommendation, can review how ‘prepared’ the house is for an earthquake. We will check how well the house is attached to its foundation and complete the City of Seattle’s hazard assessment check list.
The home owner we will then be provided with a written report, and if necessary, a recommendation for retrofitting the house. We can also provide an estimate for completing the improvements. The report and repair list may be helpful if you are thinking about getting earthquake insurance.
Disclaimer: The house may fall outside the scope of this program. In that case, an engineer will need to provide a review of the house. Alpha Builder is not an engineering firm, but we can provide a referral to a qualified engineer.