Pasadena · General Construction
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“Title 24 energy compliance is mandatory for window and door replacements in California, not just new construction. All replacement windows and doors must meet NFRC U-factor and SHGC ratings appropriate for your climate zone. In the San Fernando Valley (Climate Zone 9), you need a U-factor ≤0.32 and SHGC ≤0.25 for west and south-facing glazing. Your window salesperson may not know this. Your contractor must.”
Request NFRC performance ratings (U-factor and SHGC) in writing for every window specification. NFRC ratings are independently tested and labeled on every compliant window. In California Climate Zone 9 (San Fernando Valley), the required U-factor is ≤0.32 and SHGC is ≤0.25 for west and south exposures. Without the NFRC label, you can't verify code compliance.
This 1924 Craftsman bungalow in Pasadena's Bungalow Heaven Historic Preservation Overlay Zone (HPOZ) needed 12 windows replaced. The original single-pane wood windows were warped, painted shut, and had failed glazing. However, HPOZ regulations require replacement windows to match the original profiles, material, and divided light patterns.
NP Line Design specified custom wood windows from a manufacturer specializing in historic replacement. Each window was measured and built to match the original dimensions, muntin profiles, and sill details. The windows are true divided light (TDL) — not applied grids — with insulated glass units meeting Title 24 U-factor and SHGC requirements.
Installation involved carefully removing the original windows, preserving the wood casings and trim, and inserting the new units. Exterior trim was repaired where needed with Bondo wood filler and primed with oil-based primer before latex top coat. Interior stops were reinstalled with new glazing points.
The HPOZ application required photographs of each existing window, manufacturer cut sheets showing the matching profiles, and a letter of compliance from NP Line Design certifying the replacement windows match the original character. The Pasadena Design Review Board approved the application in 3 weeks.
Three of the twelve windows had non-standard sizes (not matching any catalog dimensions), requiring truly custom fabrication with individual measurements. The manufacturer's lead time for custom sizes was 8 weeks versus 4 weeks for standard catalog sizes, potentially doubling the project timeline. Additionally, one window in the living room had a curved top (eyebrow arch) that required specialty woodworking and steam-bent muntins — a technique few manufacturers still offer. The HPOZ application itself required detailed documentation including side-by-side comparison photographs and manufacturer specifications proving the replacements match originals.
NP Line Design ordered all 12 windows simultaneously from the same manufacturer, with the 3 custom units and the curved-top unit flagged for priority fabrication in the same production run. We scheduled the installation date based on the longest lead time (8 weeks) so all windows arrived together for a single mobilization. The curved-top window was fabricated using a custom bending jig built specifically for this order. Our HPOZ application package included detailed photographs of each existing window alongside the manufacturer's profile drawings, which resulted in first-pass approval from the Pasadena Design Review Board. Installation of all 12 windows was completed in 5 working days.
Before
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After
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Light, style, and energy savings
Window & Door Portfolio
NP Line Design handles residential and commercial construction throughout Los Angeles County including room additions, roofing, painting, seismic retrofits, water and fire damage restoration, new construction, and commercial tenant improvements. CSLB License #1105249.
Room additions in LA cost $300 to $600 per square foot depending on complexity. A 400 sqft second-story addition typically costs $150,000 to $250,000. Ground-floor additions are generally 20-30% less expensive than second-story additions.
Yes. NP Line Design handles insurance restoration projects for water damage, fire damage, and storm damage. We document all damage, work directly with adjusters, and manage the entire claims process on your behalf.
Yes. NP Line Design holds California General Contractor License #1105249 (B-license), is bonded, insured, and BBB A+ Accredited. We carry general liability and workers' compensation coverage on every project.
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