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A mid-century modern Eichler-style home in a Silicon Valley neighborhood — San Mateo, California service area

Structural Pest Control

Termite Control in San Mateo, CA

101 Exterminators handles termite control in San Mateo as a California-licensed structural pest company, SPCB Lic. #9119, in business since 2005. Most of this city went up after the war, but Hayward Park and Baywood go back to the 1920s. Which termite you have depends largely on where the property sits between Sugarloaf Mountain and the Bay. We inspect, report by section, then treat.

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Local Context

Two Termite Species, Sorted by Elevation Between Sugarloaf and the Bay

San Mateo runs uphill from tidal marsh to the Santa Cruz Mountains foothills, and termite pressure sorts itself along that grade. Up in the Highlands, San Mateo Park and Baywood the ground drains and the framing stays dry — that is western drywood territory. Incisitermes minor never touches soil. A colony works inside a rafter or a window header for years, and the first thing an owner sees is a small cone of six-sided frass pellets on a sill below a pinhole.

Down the hill it changes. Shoreview, North Shoreview, Fiesta Gardens and the streets around Marina Lagoon sit on low bayshore ground where the water table stays high and the soil never really dries between November and April, when nearly all of the city's 19 to 21 inches of rain arrives. That is subterranean ground. Reticulitermes colonies live in the soil and build pencil-width mud tubes up stem walls, pier blocks and slab edges to reach wood. The evidence is mud, not pellets.

The middle of the city complicates both. The postwar build-out sits between the two zones: slab-on-grade ranch houses, and the post-and-beam Eichler tracts in the San Mateo Highlands and 19th Avenue Park, with low-slope roofs, wide overhangs and exposed beam ends that drywood termites enter from above while subterranean termites come up through slab cracks and plumbing penetrations below. One inspection has to look both directions.

How We Work in San Mateo

We read the address before we read the house. On a Baywood or San Mateo Park property we go to the roofline first — eaves, fascia, rafter tails and attic framing — because that is where drywood termites get in. In Shoreview, or anywhere near Seal Slough, we go under the floor instead and check pier blocks, the sill plate and the stem wall for mud tubes. Every finding is photographed and split into Section 1 and Section 2 on a state-compliant WDO report.

San Mateo Climate

San Mateo sits 46 feet above the bay with a mild Peninsula climate. January lows average about 42°F and September highs about 78°F, and rain arrives on roughly 60 days a year for a total near 19 inches. Nothing in that range forces a winter shutdown. Argentine ants forage through January, and wall cavities stay warm enough that drywood colonies keep working between swarms. Drywood swarmers fly in the late-summer window, August through October, on warm afternoons at the end of a heat spell; subterranean swarms come with the rains, February through May.

Housing Stock

Three building eras stack up inside one city. The oldest, in Hayward Park, Baywood, San Mateo Park and North Central, dates to the estate subdivisions that followed 1906: dense old-growth redwood and Douglas fir framing, raised foundations, and crawl spaces a technician can actually get into. Post-war tract blocks fill the middle of the city, most of them on shallow slabs with tight or no crawl access. Then there is Bay Meadows, built on the old racetrack from the 2010s onward, along with the lagoon-side blocks at Shoreview and Fiesta Gardens that went up on filled bay margin. A 1912 bungalow and a 2015 podium building do not fail the same way, and they do not get inspected the same way.

Why Local Expertise Matters

Peninsula escrow does not wait. A San Mateo listing that turns up Section 1 findings in a 1915 crawl space needs the report written correctly the first time, because the correction bid, the lender and the closing date all hang off it. We have been licensed in California since 2005, we hold SPCB License #9119, and our reports are filed with the Structural Pest Control Board. That experience covers both ends of San Mateo's range: original-growth framing in the pre-war neighborhoods and slab-on-grade construction at Bay Meadows.

Warning Signs

Signs You Need Termites Service in San Mateo

We perform thorough visual inspections of all accessible structural wood, attic spaces, crawl spaces, fencing, and exterior wood. Our reports clearly distinguish Section 1 conditions (active infestations requiring immediate treatment) from Section 2 conditions (conditions that are likely to lead to infestation). We issue California-required WDO reports for real estate transactions and carry the licensing required by the Structural Pest Control Board.

Hollow-sounding wood when tapped — galleries eaten from inside

Frass (fine sawdust-like pellets) near baseboards or windowsills — drywood termite excrement

Discarded wings near doors or windows in spring — swarmers leaving to start new colonies

Blistering or bubbling paint on wood surfaces — subterranean tunnel activity underneath

Mud tubes running up foundation walls or piers — subterranean termite foraging trails

Soft or sagging flooring near walls — severe structural damage to subfloor joists

Small holes in wood with discoloration around the edges

Real estate transaction requiring a WDO inspection and clearance report

How It Works

Our Termites Process in San Mateo

Every job follows the same methodical approach — no shortcuts, no guesswork. Here is what to expect when you work with us in San Mateo.

01

Comprehensive Inspection

Our licensed inspector examines all accessible wood, crawl spaces, attic framing, exterior siding, eaves, and fencing. We document every finding with photos and written notes.

02

WDO Report & Recommendations

You receive a state-compliant Structural Pest Control Report distinguishing active infestations, wood damage, and conducive conditions. No confusing fine print.

03

Targeted Treatment Plan

We recommend the most effective and least invasive treatment — whether that's localized spot treatment, fumigation for widespread drywood infestation, or subterranean bait systems.

04

Treatment & Clearance

We execute the treatment per plan, return for any follow-up needed, and issue a Completion Notice clearing the structure once all Section 1 items are resolved.

Why 101 Exterminators

Termites You Can Count On in San Mateo

State-Licensed Inspectors

Our inspectors hold California Structural Pest Control licenses and are compliant with SPCB regulations for both inspections and treatments.

WDO Reports for Real Estate

We issue the Structural Pest Control Reports required for California home sales, refinancing, and VA/FHA loans — accepted by all lenders and escrow companies.

Both Termite Species Covered

Central California has both drywood and subterranean termites. We identify which species is present and apply the treatment protocol specific to each.

Free Re-Inspection Policy

If signs return within our warranty period, we come back at no charge. Our work is backed, not just guaranteed on paper.

Common Questions

Termite Control FAQs for San Mateo

Are termites in the San Mateo Highlands different from the ones near Marina Lagoon?

Usually yes — elevation sorts the species. The Highlands, San Mateo Park and Baywood drain well, so drywood termites (Incisitermes minor) dominate there and leave dry frass pellets under kick-out holes in eaves and window trim. Around Marina Lagoon, Shoreview and the bayshore streets the water table stays high and subterranean termites (Reticulitermes) build mud tubes up foundations instead. The treatments are not interchangeable, so the inspection has to establish which one you have.

Does a slab foundation in San Mateo protect a house from termites?

No — it changes which termite you get. Subterranean termites move up through slab cracks, expansion joints and plumbing penetrations to reach the sill plate, so a slab is a route rather than a barrier. Drywood termites ignore the foundation entirely and enter at exposed beam ends and low-slope roof edges, which the post-and-beam houses in the Highlands and 19th Avenue Park leave open to weather. We check both on slab properties.

When do termites swarm in San Mateo?

Drywood swarms come on warm evenings in late summer and fall; subterranean flights follow the winter rains in late winter and early spring. San Mateo's marine layer holds summer highs around the mid-70s, which spreads drywood flights across more evenings than hotter inland cities get. Discarded wings on a windowsill or inside a light fixture are what most owners notice first. Save a few — identification changes the treatment.

Local Pest Pressure

Common Pests We Treat in San Mateo

Every area has its own pest profile shaped by climate, housing, and geography. These are the pests we see and treat most often in San Mateo — tap any one to learn how to identify it and what treatment involves.

Drywood Termites

The estate subdivisions built after the 1906 earthquake left Hayward Park, Baywood and North Central full of century-old redwood and fir framing

Subterranean Termites

The low blocks around Marina Lagoon, Shoreview and Seal Slough sit on a shallow water table that keeps colonies foraging year round

Roof Rats

Mature street trees in the pre-war neighborhoods put branches on rooflines, which is how roof rats reach attics

Argentine Ants

Supercolonies in the older landscaped blocks come inside twice a year, first out of waterlogged nests and later in search of water

German Cockroaches

Restaurant density downtown and around Hillsdale sustains commercial German cockroach pressure that residential-only suburbs do not carry

Termite Control · San Mateo

Free Pest Evaluation in San Mateo

CA licensed and insured. Written estimate before any work begins. Urgent situations in San Mateo are prioritized.

Schedule an Inspection(831) 500-1613
Trusted by San Mateo families since 2005