By Homes by Marlyse
We get asked a lot about foundation maintenance once clients settle into an older LA home, and for good reason. Between expansive clay soils, seismic activity, and a dry summer followed by a wet winter every year, foundations here face real stress that homeowners in a lot of other markets simply don't deal with. Here's what we recommend to keep a foundation in good shape over time.
Key Takeaways
- LA's clay soil expands and contracts with the wet-dry cycle, putting real stress on foundations
- Small warning signs, like sticking doors or drywall cracks, are worth taking seriously
- Managing drainage around the home helps prevent a lot of foundation movement
- Older homes may qualify for state-funded seismic retrofit assistance
Why LA's Soil and Seismic Activity Put Extra Stress on Foundations
Much of the LA Basin sits on clay-rich soil that swells when it absorbs water and shrinks as it dries out, and that cycle repeats every year with the region's wet winters and dry summers. Over years and decades, that repeated movement can cause a foundation to crack, shift, or settle unevenly. Add in the region's seismic activity, and it's easy to see why foundation maintenance matters more here than in a lot of other markets.
What Makes LA Foundations Uniquely Vulnerable
- Expansive clay soil that shrinks and swells with seasonal moisture changes
- A wet-dry seasonal cycle that repeats this stress year after year
- Regular seismic activity that can aggravate existing foundation weaknesses
- Aging housing stock built before modern seismic building codes
Watching for Early Warning Signs
Most serious foundation problems start small, which is exactly why it's worth paying attention to minor changes around the home. Doors and windows that suddenly stick, new cracks in drywall or exterior stucco, and uneven or sloping floors are all early signs worth investigating. Catching these early usually means a simpler, less expensive fix than waiting until the problem becomes obvious.
Warning Signs Worth Watching For
- Doors or windows that stick or no longer close properly
- New cracks appearing in drywall, stucco, or foundation walls
- Floors that feel uneven or noticeably sloped
- Gaps forming between walls, ceilings, or window frames
Managing Drainage to Protect Against Soil Movement
Water is one of the biggest factors in foundation health here, since LA's expansive clay soil reacts strongly to changes in moisture. During dry periods, soil can shrink away from the foundation, and when rain returns, water can seep into those gaps and cause uneven swelling underneath the home. Keeping water moving away from the foundation, rather than pooling near it, helps reduce this kind of stress significantly.
Drainage Habits Worth Maintaining
- Making sure gutters and downspouts direct water well away from the foundation
- Grading soil around the home so water flows away, not toward it
- Watching for pooling water near the foundation after heavy rain
- Keeping irrigation and sprinklers from oversaturating soil right next to the house
Understanding Seismic Retrofitting and the Earthquake Brace + Bolt Program
Many older LA homes, especially those built before 1980 with a raised foundation or crawl space, were never seismically retrofitted to modern standards. Seismic retrofitting typically involves bolting the home's frame to its foundation and bracing cripple walls, which reduces the risk of a home shifting off its foundation during an earthquake. Homes in eligible ZIP codes, which cover much of LA County, may qualify for the state's Earthquake Brace + Bolt program, which has helped tens of thousands of California homeowners retrofit their homes since it launched.
What Seismic Retrofitting Typically Involves
- Bolting the home's frame to the foundation
- Bracing cripple walls to prevent them from collapsing during shaking
- Checking eligibility for the Earthquake Brace + Bolt program if the home qualifies
- Working with a licensed contractor experienced in seismic retrofit work specifically
Extra Considerations for Hillside Homes
Homes built on a slope, like many in the Hollywood Hills or other hillside neighborhoods, face additional foundation considerations beyond flat-lot properties. Foundations resting on loose surface material rather than solid bedrock are more prone to settling and slope movement over time, which is why a geotechnical investigation matters more for these properties. If you're buying or maintaining a hillside home, understanding what the foundation actually sits on is worth prioritizing early.
Why Hillside Properties Need Extra Attention
- Whether the foundation sits on stable bedrock or looser surface material
- How drainage is managed on sloped lots specifically
- Whether retaining walls on the property are in good condition
- The value of a geotechnical investigation before buying or renovating
FAQs
How often should we have our foundation inspected?
We generally recommend an inspection every year or two, and definitely after any noticeable seismic activity. Catching small issues early is almost always less costly than waiting.
Is seismic retrofitting really necessary for an older home?
We think it's worth strongly considering, especially for homes built before 1980 with a raised foundation. It's one of the more cost-effective structural improvements available for older LA homes.
Do hillside homes really need different foundation care than flat-lot homes?
Yes, and we walk clients through this difference often. What the foundation actually sits on, whether that's solid bedrock or looser surface material, changes how much attention drainage and slope stability need.
Contact Homes by Marlyse Today
Understanding a home's foundation is part of understanding what you're actually buying or maintaining here in LA. We're happy to talk through what to look for, whether you're settling into a home or getting one ready to sell.
Reach out to Homes by Marlyse, and let's talk through what your home's foundation might need.
Reach out to Homes by Marlyse, and let's talk through what your home's foundation might need.
