Every month, we seek to bring our readers insight from the worlds of home construction, home repair, and home maintenance straight from local Northwest Washington contractors in a segment we call “3 Questions.” Yep, you guessed it: we ask three questions, and the contractors answer them.
This month, we learn about structural issues with Gary Sturdy, PE, owner at Sturdy Engineering Corporation in Anacortes. Additionally, more information about related structural engineering topics is available via our Real Estate Unveiled! podcast page.
Q1: My old house appears to have settled over time and is “leaning” somewhat.  What are some things I should be on the lookout for to see if I need a contractor to further evaluate?
A gradual settling observed over years is an indication of poor soil conditions below the foundation.  The problem must first be identified; applying a fix to the symptoms may worsen it.
The first objective is to determine soil conditions under the foundation, including depth of poor soils.  Once that is determined, a proper solution can be engineered to solve the problem.  As an example, adding width to the existing foundation will add weight and might create even greater settlement. 
Q2: The masonry chimney on my old house appears to have settled and isn’t perfectly plumb; I can see a gap between the chimney and the home.  How can I tell if this is historic or a major structural concern and safety issue?
A snapshot in time will not give you answers to historic events.  That gap might have been there for years without change, which would indicate that the settlement has stopped and the underlying soils are stable.  Continual monitoring with measurement over time or soil testing will determine if the underlying soils are unstable.
An engineer can help you determine how far out of plumb is safe for your particular chimney style and construction.  At that time, the engineer can determine if remedial action is imminent.
Q3: Wood destroying organisms (WDOs), like Carpenter ants, Anobiid beetles, and Pacific Dampwood termites are commonplace in the Pacific NW.  Eliminating elevated moisture is absolutely the key to keeping a home free of WDOs.  Recognizing that these insects literally eat wood structure, is there a general rule-of-thumb for when replacement may, or may not, be necessary? In older homes, for instance, minor WDO damage is commonplace, and replacing all structural elements with minor insect damage would involve substantially replacing most of the home’s structure. Is this really necessary, or is there a more practical, “real-world” approach?
Each piece of lumber has an allowable load, or maximum weight that it can withstand.  For example, a piece of lumber might only be loaded to 50-percent of its allowable value.  In this case, the bugs can eat away a significant amount of wood before safety is an issue.  On the other hand, a piece of lumber that is fully loaded cannot withstand any bug damage. An experienced engineer can determine what repairs are required for your safety, while integrating practical and economical solutions.
About Sturdy Engineering Corporation 
Sturdy Engineering Corporation in Anacortes provides structural analysis & design for residential, commercial, light industrial, recreational, and agricultural structures. These structures may utilize a variety of building materials, including wood/logs, timber frames, concrete, steel, and structural insulated panels. More information at https://www.sturdyengineering.com/#
A big “thanks” to Gary for his responses!
If you have questions or comments about structural issues or home inspections in general, tweet me (@AIHomeInspect).