Decking · Hot & dry
How a composite deck ages in San Diego, CA
In San Diego, sun is the main stress on a composite deck: UV ranks #9 of 25 cities we cover. Capped boards lighten noticeably in the first two years, then stabilize; dark colors also get hot underfoot. Model estimate: 24–31 years of service.
Storyboard
20 years in San Diego, washed yearly
San Diego’s wear fingerprint
Each bar is scaled to the highest of the 25 cities we cover; the black line marks the median.
NOAA station SAN DIEGO INTL AP (USW00023188, 2.6 km away), 1991–2020 normals · humidity & UV: NASA POWER.
What fails first here
- 1Early color fadeCapped boards lighten in the first 1–2 years, then level off. Stronger here than average: UV rank #9 of 25.
- 2Surface mildewComposite does not rot, but pollen and dirt on shaded boards feed mildew. A wash in spring and fall prevents it.
- 3Heat underfootOnly about 3 days a year top 90 °F, so surface heat is rarely an issue.
- 4Gaps & fastenersBoards expand and contract with temperature; check hidden clips and end gaps every few years.
Upkeep
San Diego maintenance calendar
Built from local normals: bar width is the share of days with rain; composite mainly needs washing.
Same city, other materials
How the alternatives age in San Diego
Pin-ready
Save it for when you build.
The 20-year storyboard as a tall pin, linking back to this page.
Composite decks in similar climates
Los Angeles, CA
San Francisco, CA
Charleston, SC
Portland, OR
New York, NY…and in very different ones
New Orleans, LA
Miami, FL
Tampa, FLQuestions San Diego owners ask
How long does a composite deck last in San Diego?
Our model puts a capped composite deck at 24–31 years in San Diego, close to typical warranty terms. The boards outlast the look: expect some early fading and surface mildew in shade.
How often should you clean a composite deck in San Diego?
Twice a year — in spring and fall. Dirt and pollen are the main thing to wash off.
Is composite worth it over cedar in San Diego?
In San Diego our model gives untreated cedar 18–24 years and composite 24–31. The gap is smaller where rot is slow, so upkeep preference decides.
Why does wood turn white or pale in San Diego?
UV breaks down lignin at the surface; rain and wind wash the loose fibers away, leaving a bleached, silvery layer. It is cosmetic until checks open up.
Model simulation, not a guarantee: south-facing, full sun, no shade or ground-contact surprises. How it works.