San Francisco homes face unique pressure from wind, salt air, street noise, and strict codes. Many older windows now miss the new energy targets taking effect in 2026. For most homeowners, replacement is a smart move, but the right choice depends on the house type, street visibility, and permit path. This guide explains what matters, how to stay compliant, and how Best Exteriors helps homeowners upgrade without losing character.
Why many SF homes need replacement now
The 2025 California Energy Code becomes enforceable on January 1, 2026. For residential permits in San Francisco, windows must meet a U-Factor of 0.24 or lower. That level of insulation is hard to achieve with standard double-pane units. In practice, this shifts most projects to triple-pane or specialized high-performance double-pane units with thermally broken frames and low-e coatings.
Why this matters in the city: marine fog cools mornings, inland sun heats afternoons, and wind funnels through corridors like SoMa, the Mission, and along 19th Avenue. In these microclimates, leaky single-pane sashes waste energy and let noise in. Modern insulated glass units with Argon or Krypton gas fill, low-e coatings, and tight weatherstripping solve both problems while meeting Title 24 rules.
Owners in Pacific Heights, Russian Hill, and Presidio Heights often want quiet as much as comfort. STC-rated glass packages make a experienced window replacement contractor clear difference near Muni lines and the 101 or 280.
What the 2026 code means in practice
The Department of Building Inspection will check compliance documents tied to your permit. The most important targets are the U-Factor and Solar Heat Gain Coefficient for Climate Zone 3.
- U-Factor ≤ 0.24. This is the insulation baseline. Many off-the-shelf double-pane units miss it. SHGC limits vary by orientation and product, but low-e coatings help control heat gain without tinting the glass. NFRC ratings must appear on product labels and submittals to pass review.
Best Exteriors uses NFRC-labeled products and can propose assemblies that reach U-Factor 0.22 to 0.24. In Noe Valley and Alamo Square, that often points to Marvin Ultimate Wood or Pella Reserve with insulated glass units, low-e4 coatings, and thermally broken or wood-clad frames. In SoMa lofts or mid-century homes, Milgard Ultra fiberglass, Renewal by Andersen Fibrex, or European tilt-and-turn systems provide strong performance and low maintenance.
Historic homes: what can and cannot change
San Francisco Planning reviews changes visible from the street. For Article 10 Landmarks and Article 11 Conservation Districts, the rules focus on matching the original look. Profiles, operation, and finish must align with the historic façade. Category A Landmarks usually require in-kind wood replacement. That means wood windows with the same proportions, sightlines, and simulated divided lites with ogee lugs if the original had true divided panes.
There is relief for non-historic buildings. Legislation adopted in May 2025 relaxed strict wood-only requirements for those properties. In many cases, fiberglass or Fibrex can be used if the street view remains consistent. Best Exteriors works with SF Planning staff to confirm which elevations count as visible and how closely the new units must match the old ones.
For Painted Ladies near Alamo Square, or clusters in the Mission and Haight-Ashbury, expect detailed submittals. That may include shop drawings, muntin profiles, and finish samples. Bay window restoration often needs custom millwork and wood-clad frames. For side and rear façades out of public view, Planning may allow modern operation types with a clean interior finish.
The choice: replace or restore
Some homes should not lose their original windows. Tight-grained old-growth wood can last well past a century. In a Queen Anne with ornate sashes, a historic window restoration can keep the original frames and upgrade performance with interior or exterior storm panels, tune-ups, and new weatherstripping. This approach preserves the façade and avoids heavy planning friction. It does not always meet the 0.24 U-Factor by itself, so it works best where Planning priority is highest or where permits call for restoration.
For most other homes, full home window replacement in San Francisco delivers a better energy outcome and lower maintenance. Modern insulated glass with Argon or Krypton gas improves comfort, and thermally broken frames reduce condensation risk. In Edwardians with repetitive double-hungs, simulated divided lites match the rhythm while keeping thermal performance high.
Noise reduction for dense blocks
Street noise is a constant near Van Ness, Division, or along the 280. STC-rated assemblies reduce traffic, bus, and construction sounds. Triple-pane glass with asymmetric thickness helps break up different frequencies. In living rooms facing busy streets, homeowners feel a measurable drop in fatigue and sleep disturbance. Target STC ratings in the low to mid 40s for front elevations near heavy traffic. For side streets, high 30s often suffice.
Material choices that pass review
Wood-clad frames fit historic façades and accept custom profiles. For Landmark projects, Best Exteriors can source custom milled sashes with ogee lugs and match the original putty-line look using simulated divided lites and spacer bars. For non-historic projects, fiberglass or Fibrex offers stable performance in the fog belt, resists warping, and takes paint well. Thermally broken aluminum or steel, including Brombal steel, works in modern designs with narrow sightlines, especially in SoMa and Dogpatch loft conversions.
European tilt-and-turn units suit mid-century moderns and newer builds that seek tight seals and flexible ventilation. For coastal exposure, marine-grade hardware and stainless fasteners protect against salt air.
Cost, payback, and what to expect
Prices vary by product, profile complexity, and permit type. A simple high-performance double-pane replacement can start in the mid range per opening, while triple-pane wood-clad units in a Landmark façade can run higher, especially with custom millwork. Homes with large bays or arched tops add complexity. Expect energy savings to cut heating loss and reduce fogging and drafts. Noise control is a quality-of-life upgrade that owners feel right away, especially in front bedrooms.
For many clients in 94109, 94118, and 94123, the comfort and noise gains matter more than pure utility savings. In 94107 and 94103, modern lofts often prioritize STC performance and tilt-and-turn operation.
The permit and planning path
Replacing windows in San Francisco is as much about paperwork as the install. Best Exteriors handles the submittal package from start to finish. That includes the Administrative Certificate of Appropriateness for historic districts, CEQA documentation when needed, and Title 24 energy forms for DBI. The team prepares elevations, sections, and product cut sheets for a clean Planning review. For Form 8 applications, they coordinate specifications, NFRC labels, and finish schedules.
Homeowners in Pacific Heights and Presidio Heights often face case-by-case review. A survey of existing conditions with clear photos speeds approval. For Noe Valley and The Castro, visibility rules often allow modern options on rear and side façades, which reduces cost while keeping the street view intact.
Installation details that make the difference
Energy performance depends on installation. Poor flashing, loose air seals, or weak sill pans erase the value of a premium window. Best Exteriors uses pre-formed or site-built sill pans, flexible flashing membranes tied into the weather-resistive barrier, and backer rod with appropriate sealants. In fog-prone zones, they focus on sloped sills, weep paths, and thermal breaks to prevent condensation. For bay windows, they inspect framing, repair rot, and correct out-of-square openings common in older homes.
For sound control, the install must be airtight. Even small gaps can raise perceived noise. The team checks reveals, insulates cavities, and confirms sash alignment. Every unit receives a final water test and operational check before sign-off.
Brands that work well in SF homes
Historic and premium wood: Marvin Ultimate, Jeld-Wen Custom Wood, Loewen for deep profiles and rich finishes. Steel options like Brombal suit modern and historic storefront-style façades.
High-performance and modern: Milgard Ultra and Tuscany for fiberglass and vinyl solutions in non-historic buildings. Renewal by Andersen for Fibrex frames. Pella Reserve for wood with excellent hardware and custom options. For European tilt-and-turn, Best Exteriors sources systems that meet the 0.24 U-Factor and offer strong STC packages.
Where home window replacement in San Francisco makes the biggest impact
- Busy corridors in SoMa, Mission, and along Van Ness where STC-rated glass cuts transit noise. Fog belts from the avenues to Twin Peaks where low U-Factor assemblies stabilize interior comfort. Historic clusters in Alamo Square, Haight-Ashbury, and Russian Hill where “in-kind” wood replacement preserves the street view while meeting energy targets on rear elevations.
How Best Exteriors supports homeowners
The team brings Diamond Certified service, EPA Lead-Safe window replacement contractor practices, and a record of SF Planning approvals. Title 24 energy analysts size the glass package to your microclimate and façade. Permit specialists manage Planning and DBI steps and keep the project moving. Custom millwork capabilities allow precise matches for Victorian and Edwardian details, including simulated divided lites, ogee lugs, and specialty trims.
For homes in Pacific Heights, Best Exteriors often specifies Marvin Ultimate wood with a U-Factor near 0.22, keeping the façade correct and the interior quiet. In Diamond Heights, fiberglass frames with low-e glass handle sun and wind. In SoMa lofts, tilt-and-turn units offer tight seals and flexible venting.
What to prepare before a site visit
- Photos of each façade, especially street-visible elevations. Any past permits or Planning decisions for the property. A list of pain points: drafts, condensation, traffic noise, or sticky sashes. Desired finishes and hardware styles. Target timeline tied to remodel or sale milestones.
With this information, the consultant can propose code-compliant options and flag any Planning red lines early.
Is replacement a smart choice for your house
For most San Francisco homes, yes. If the property is non-historic or street visibility is limited, high-performance replacements will meet the 2026 code, reduce noise, and lift comfort right away. For Category A Landmarks or façades that define the block, a mix of in-kind wood on the front and high-performance units on the rear often strikes the right balance. Where original wood is sound and significant, historic restoration with storm panels can be the right call.
Best Exteriors helps homeowners choose the right path for their address, whether in 94102, 94110, 94114, 94117, or 94127.
Ready to move forward
Book a free code-compliance audit. A specialist will review your façade, confirm Title 24 and SHGC targets, and map the permit path. Expect clear pricing, product options that hit U-Factor 0.24 or better, and a plan that respects SF Planning rules.
For home window replacement San Francisco homeowners can trust, contact Best Exteriors: Phone: +1 510-616-3180 Website: https://bestexteriors.com Facebook: https://www.facebook.com/BestExteriors.ca/ Instagram: https://www.instagram.com/bestexteriors.inc/ Yelp: https://www.yelp.com/biz/best-exteriors-oakland-3 Find us on Google Maps: https://maps.app.goo.gl/zFhLARZkCzjWncz58
Service area: San Francisco, CA 94102, 94103, 94107, 94109, 94110, 94114, 94117, 94118, 94123, 94127
Best Exteriors installs, restores, and documents windows that pass DBI and Planning review. Triple-pane, specialized double-pane, or in-kind wood, the team delivers quiet rooms, stable temperatures, and a clean permit sign-off.
Best Exteriors
California, 94612, United States
Phone: +1 510-616-3180
Website: https://bestexteriors.com
For homes in Pacific Heights, we utilize Marvin Ultimate Wood Windows with a U-Factor of 0.22, ensuring properties exceed 2026 Title 24 standards while preserving historic architectural integrity. Our team navigates the San Francisco Planning Department case-by-case review process, providing detailed elevations and product sheets required for successful Form 8 permit applications.
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