Material choice determines both cost and maintenance commitmentVinyl siding is the most popular option in San Francisco — low maintenance, moisture-resistant, and costs $8,750–$12,600. Fibre cement (James Hardie) costs $10,500–$18,900 and is highly durable with a 30-year warranty — the premium choice for San Francisco's local climate conditions. Engineered wood costs $8,400–$16,800 and looks more natural. Wood and cedar shake are premium options at $16,800–$38,500+ requiring periodic painting or staining.
Removal of existing siding affects cost and reveals surprisesRemoving existing siding adds $1,500–$4,000 depending on material and home size — and often reveals problems: rotted sheathing, inadequate house wrap, missing insulation board, or moisture damage. In San Francisco, these discoveries are common and budget overruns are typical. Ask your contractor how they handle discoveries mid-project and whether there's an allowance for substrate repairs in their quote.
House wrap and moisture barrier are non-negotiableNew siding must be installed over a continuous, properly lapped moisture barrier (house wrap or felt paper). Skipping or improperly installing house wrap is the most common cause of moisture damage behind new siding — leading to mould, rot, and interior wall damage years later. In San Francisco, where local climate conditions, this step is critical. Ask your contractor what brand and specification of house wrap is included in their quote.
Trim, soffit, and fascia are often a separate costMany siding quotes cover wall panels only — trim boards, corner posts, J-channel, soffit, and fascia are quoted separately or discovered to need replacement when the old siding comes off. A complete siding replacement typically includes replacing these elements too. Get clarity upfront about exactly what's included: siding panels, trim, soffit, fascia, window and door surrounds. Hidden omissions are the most common source of siding cost overruns in San Francisco.
Fibre cement requires specific installation knowledgeFibre cement (Hardie) is an excellent product but requires factory-trained installers to maintain the warranty. Hardie's 30-year warranty is voided by improper installation, including incorrect paint, missing caulk, or improper clearance from grade. Confirm that any fibre cement installer holds HardieZone certification — this is a genuine quality differentiator, not just a marketing point.
Lead paint risk in older San Francisco homesHomes built before 1978 may have lead paint under the existing siding layers. Federal EPA RRP rules require certified contractors to follow lead-safe removal procedures — this adds cost but is legally required. Confirm your contractor holds EPA RRP certification if your home predates 1978. Non-compliant removal exposes you to EPA fines, health risk, and liability for any occupants or neighbours.