24H Mold Inspection of Riverside

Frank Miller built the Mission Inn in seven major phases between 1902 and 1931, filling a full downtown block with Mission Revival arcades, domes, and courtyards, and the streets around it hold early-twentieth-century masonry commercial buildings now converted to restaurants, offices, lofts, and condominiums. Brick and lightly reinforced masonry wick water and hold it, flat roofs pond behind parapets, and conversions add showers and kitchens to buildings designed for retail or storage, often over slabs with no vapor barrier. Leaks from upper units surface in the spaces below, and decades of remodels have opened and closed walls over old water damage.

South of downtown, the Wood Streets and the neighboring early-twentieth-century blocks are lined with Craftsman bungalows, Spanish Colonial Revival homes, and period revival houses under a canopy of mature street trees. Most stand on raised wood foundations over crawl spaces built without vapor barriers, with original or early-replacement galvanized plumbing and cast-iron drains. A century of re-roofs, additions, and remodels adds seams where newer work meets original walls. Damp crawl space soil after wet winters, subfloor growth beneath bathrooms and kitchens, and roots invading sewer laterals while leaves clog gutters and valleys define the moisture risk here.

Riverside's citrus industry began with the parent navel orange trees Eliza Tibbets planted in 1873 — one still grows at Magnolia and Arlington avenues — and Victoria Avenue was laid out in 1892 to link Arlington Heights to downtown, landscaped under pioneer designer Franz Hosp. Homes along the avenue and across the former grove lands range from ranch-era houses to mid-century homes on lots once irrigated as orchards. Landscape and remnant grove irrigation keep soil damp against foundations, mature trees send roots toward sewer lines, and outbuildings and garages converted to living space sit on unsealed slabs.

In March 1938 the river overtopped its banks and flooded part of northwest Riverside, driving families from homes in the northern part of the city. The low ground along the river corridor and around Fairmount Park — designed by the Olmsted firm, commissioned in 1911 — is where the water table runs highest and storm runoff collects fastest. Moisture here tends to arrive from below: damp crawl space soil under older raised-foundation homes, vapor rising through slabs poured without vapor barriers, and growth along the bottom of drywall on exterior walls after a wet winter.

The neighborhoods around UC Riverside carry a large stock of houses rented by the room and apartment complexes that turn over every academic year, where high occupancy produces more shower, cooking, and laundry moisture than older units were built to vent. East of campus, Canyon Crest climbs toward the Box Springs Mountains on graded pads with retaining walls and terraced yards. The granitic slopes shed water quickly, concentrating storm runoff against uphill walls and into the joint between slab and foundation, while hillside condominium complexes add shared walls and roofs that let a leak in one unit reach the next.