Exterior Siding & Painting in San Jose, CA

The missing piece at that last location has a name, which is worth knowing because it is left off so routinely. A kick-out flashing is the small formed piece at the bottom of a roof-to-wall junction that throws runoff away from the wall and into the gutter instead of letting it run down behind the cladding. It costs almost nothing and its absence produces rot that gets discovered years later from the inside. At the base of a stucco wall there is a weep screed, a perforated edge that lets water which made it into the assembly drain out.

Bury it under a raised planting bed, a patio slab poured tight to the house, or a deep layer of bark, and the wall no longer has a way to drain. That condition is common on lots that have been landscaped two or three times over the decades, and it is worth checking before anyone quotes a repaint. Stucco behaves differently from board siding and has to be diagnosed differently. A traditional three-coat system is cement plaster applied over metal lath over two layers of building paper.

It is rigid and heavy and it moves slightly as the house moves. Fine hairline cracking is normal in cement plaster and is mostly cosmetic. Cracks running diagonally out of the corners of window and door openings are telling you the wall is flexing, which is information rather than a defect to be filled. Cracks that actually leak are usually not the ones in the field at all, but the joints at penetrations and terminations where the plaster stops and something else starts.

Patching is straightforward as repair work and unforgiving as cosmetics: matching an existing texture takes a practiced hand, and matching the color of thirty-year-old weathered plaster with fresh material does not really happen. That is why stucco repair is normally followed by coating the entire elevation, and why the elevation rather than the patch is the sensible unit of work. Elastomeric coatings come up in nearly every stucco conversation and deserve a straight answer. They are thick, flexible, high-build coatings that bridge hairline cracks and shed water well, and on the right wall they perform for a long time.

The catch is permeance. A film that thick slows drying to the outside, so a wall that is taking on water somewhere, a buried weep screed, a failed window head, a leaking penetration, now has less capacity to dry, and the coating can blister and peel in sheets as trapped moisture pushes back through. Elastomeric is a good decision on a wall whose details have been made watertight and which needs crack bridging. It is a poor decision as a way to stop a leak that has not been found.

Fiber cement is the common replacement for failing wood siding in this area, and it has rules of its own. Cutting it releases respirable crystalline silica, so it is cut with a shrouded blade on a vacuum or cut wet, which is a worker safety obligation rather than a preference about dust. It is fastened into framing rather than into sheathing alone, blind nailed at the specified spacing so each fastener is covered by the course above.

Butt joints get a flashing piece behind them and are left uncaulked, which surprises people who assume every seam wants sealant; that joint is designed to let incidental water reach the drainage plane and get out. Cut edges are primed, because a cut face is raw and absorbent. The manufacturer also specifies clearances: a gap between the bottom course and the ground, a gap where siding meets a roof surface, a gap where it meets a deck or patio.

Those exist so the material is not standing in water or wicking moisture out of wet concrete, and they get violated constantly by installers trying to make a last course look tidy. A violated clearance shortens the life of the wall and voids the material warranty at the same time. Wood and engineered wood fail predictably at end grain and at fasteners. Cedar and redwood, both common in older Bay Area exteriors, carry tannins that bleed through a finish coat and leave brown staining unless the surface is sealed first with a stain-blocking primer.

Cut ends absorb water far faster than faces, so they get primed before installation rather than after. Boards installed wet shrink and open their joints as they dry; boards installed bone dry into a wet season swell and cup. Fasteners that were the wrong metal for the wood leave dark streaks running down from every nail head, and repainting over that without dealing with it simply puts a fresh coat over a stain that comes back through.

The painting itself is mostly preparation, and the order is not negotiable. Washing comes first, at a pressure low enough to clean without driving water behind the cladding or eroding old plaster, because a pressure washer aggressive enough to strip paint is also aggressive enough to fill a wall cavity. Mildew, which grows readily on the shaded north and east elevations here, has to be killed with an appropriate cleaner; painting over living growth gives it a new surface and it reappears within a year.

Failing paint is scraped back to a sound edge and the transition sanded so the step in film thickness does not telegraph through the new coats. Bare wood and bare metal are primed with a primer chosen for that substrate, and new stucco has to cure before it is coated because fresh cement plaster is strongly alkaline and will attack a coating not formulated for it. Wood gets checked with a moisture meter rather than by hand, since a surface that looks dry after a wet week frequently is not.

Caulking goes in after priming rather than before, because sealant bonds far better to a primed surface than to chalky weathered material, and the joints that get sealed are the vertical trim-to-cladding joints and the penetrations, while the drainage gaps are deliberately left open. Application is governed by the weather and by the label. Coatings have an air temperature range and a surface temperature requirement, and the marine layer that pushes into the valley overnight leaves real moisture on a wall until the sun has been on it for a while.

Paint applied onto a damp surface early in the morning, or applied late enough in the day that the film is still soft when the surface drops below the dew point, produces surfactant leaching, which is the brown or glossy streaking that appears on a fresh wall after the first heavy dew. That is a timing failure rather than a product failure. The number that quietly determines how long the whole job lasts is spread rate.

Every product data sheet states the square footage a gallon covers to reach the intended dry film thickness, and stretching that figure is the cheapest way to make a bid look competitive and the hardest thing for a homeowner to detect from the sidewalk. On textured stucco, spraying puts the material on evenly and back-rolling drives it into the texture so it bonds rather than bridging over the low spots. In neighborhoods built this tightly, overspray lands on somebody's car, so masking and containment are part of the work rather than an afterthought.

One more consideration on older houses. Federal rules require that renovation disturbing painted surfaces in homes built before 1978 be carried out using lead-safe work practices by a certified renovator, and a large share of San Jose's housing stock predates that year. Testing establishes whether the rule applies to your project. Ask any contractor bidding pre-1978 exterior work how they handle it and ask to see the certification rather than accept the answer on faith.