Case Study
NYC TOWNHOUSE RESIDENCE
NYC Townhouse Residence
New York, NY
Custom SkyFloor® Series 2000 thermally broken walkable skylight system — delivering natural light into a private luxury living room and art gallery below, with zero loss of rooftop terrace space.
At a Glance
Client: Private Residential Client
Location: New York, NY
Application: Residential Rooftop Terrace
Completed: 2017
Architect: SPAN Architecture
Installer: Riverside Builders
Glass System: SkyFloor® Series 2000 — Thermally Broken Walkable Skylight
Frame Type: Proprietary aluminum thermally broken recessed frame with T-rafters
Anti-Slip Texture: Yorlux™ — S-Series Satin (ANSI A326.3 DCOF Tested)
Overall Dimensions: 21′ – 3¾” × 6′ – 3 1/16″ (exposed frame)
Glass Panels: 5 panels @ 5′ – 11/32″ × 2′ – 11 3/32″ 2 panels @ 6′ – 11 9/32″ × 2′ – 11 3/32″ (7 panels total — 1 skylight unit)
Skylight Compliance: ICC-ES Certified · NFRC Certified · NYC Energy Code Compliant · ANSI A326.3 Anti-Slip Tested · ASTM E2751 · AAMA 2605
Project Highlights
7 Panels
Custom Glass Panels
100%
Terrace Preserved
ICC / NFRC
Certified System
Executive Summary
Glass Flooring Systems designed and supplied a SkyFloor® Series 2000 thermally broken walkable skylight system at a private luxury townhouse in New York City. Working alongside SPAN Architecture and Riverside Builders, our team engineered a flush-mounted structural glass solution that introduces abundant natural light into a below-grade living room and private art gallery — without sacrificing a single square foot of the rooftop terrace above. The SkyFloor® Series 2000 is ICC-ES certified and NFRC rated, meeting New York City energy codes and enabling a smooth plan review, permitting, and inspection process. The result is architecturally seamless by day — and dramatically illuminated at night.
The Challenge
Project Overview
The owners of this Greenwich Village townhouse needed a way to bring natural light into their private living room and curated art gallery, which sat directly beneath the rooftop terrace. Conventional raised skylight units were not an option — the clients demanded the full terrace area remain usable and that the skylight sit flush with the terrace deck, with no visible frames, curbs, or raised elements interrupting the rooftop.
Key Constraints
- Introduce natural daylight into the living room and art gallery below the rooftop terrace
- Preserve 100% of the rooftop terrace’s usable square footage — no raised or protruding skylight units
- Maintain the home’s sleek, modern architectural aesthetic with a flush, seamless installation
- Provide interior privacy while maximizing light transmission through the glass panels
- Meet NYC structural load, energy code, and building code requirements for a walkable glass surface
- Navigate NYC’s building department permitting and inspection process efficiently
Why This Mattered
For a residence and art collection of this caliber, natural light is not optional — it is essential to how the spaces are experienced. A traditional skylight approach would have compromised the terrace layout and the clean architectural lines the design required. The project demanded a bespoke structural glass engineering solution with proven compliance credentials.
Our Solution
System: SkyFloor® Series 2000
Glass Flooring Systems specified the SkyFloor® Series 2000 — our ultra-high performance, NFRC- and ICC-ES-certified walkable skylight for demanding residential applications where thermal performance, structural integrity, code compliance, and design elegance are all required simultaneously.
Frame & Structure
- Proprietary 6063-T6 aluminum thermally broken recessed frame with T-rafter substructure
- Frame recessed flush into the terrace deck — no element protrudes above the terrace surface
- Patented integrated gutter and weep system for superior waterproofing performance
- PPG Coraflon® painted finish meeting AAMA 2605 — standard black finish
- Custom-fabricated to the project’s exact dimensional requirements with project-specific stamped shop drawings
Waterproofing & Weather Performance
The SkyFloor® Series 2000 is engineered for exceptional waterproofing performance — a critical requirement for a rooftop terrace in New York City, where heavy rain, freeze-thaw cycles, and standing moisture demand a system with zero tolerance for failure. Every unit is made to order and integrates seamlessly with modern roofing systems, including liquid-applied and rolled rubber membranes.
- Integrated monolithic thermally broken aluminum frame — single-piece construction minimizes joints and eliminates the weak points where water can infiltrate multi-part competitor frames
- Redundant multi-layer drainage system: perimeter gutters, internal weep system, and optional sloped sub-pans — incidental moisture is captured and redirected away from the structure
- Custom factory-applied flashing details — manufactured to align precisely with the project’s specified roofing membrane, eliminating on-site guesswork and reducing potential failure points
- Compatible with liquid-applied membranes and rolled rubber roofing — engineered to accommodate the waterproofing method specified for each project
Anti-Slip Surface: Yorlux™
All walkable glass panels are finished with the Yorlux™ anti-slip texture from Glass Flooring Systems’ S-Series Satin collection. Yorlux™ was selected for its combination of ANSI A326.3-compliant slip resistance, diffuse light transmission, and privacy — the satin finish allows daylight through while obscuring the view from above into the living spaces below.
- ANSI A326.3 Dynamic Coefficient of Friction (DCOF) tested — the only nationally recognized anti-slip standard in the U.S.
- Tested using BOT-3000E tribometer — wet and dry conditions
| Texture | Condition | DCOF Result | ANSI A326.3 Status |
|---|---|---|---|
| Yorlux™ | Dry | 0.84 | ✔ PASS |
| Yorlux™ | Wet | 0.87 | ✔ PASS |
| Texture | Yorlux |
| Condition | Dry |
| DCOF Result | 0.84 |
| ANSI A326.3 Status | ✔ PASS |
| Texture | Yorlux |
| Condition | Wet |
| DCOF Result | 0.87 |
| ANSI A326.3 Status | ✔ PASS |
Panel Dimensions
The skylight comprises 7 custom glass panels in two configurations within a single integrated frame unit:
| Panel | Qty | Width | Height |
|---|---|---|---|
| Type A | 5 panels | 5′ – 11/32″ | 2′ – 11 3/32″ |
| Type B | 2 panels | 6′ – 11 9/32″ | 2′ – 11 3/32″ |
| Overall Frame | 1 unit / 7 panels | 21′ – 3¾” | 6′ – 3 1/16″ |
| Panel | Type A |
| Qty | 5 panels |
| Width | 5′ – 11/32″ |
| Height | 2′ – 11 3/32″ |
| Panel | Type B |
| Qty | 2 panels |
| Width | 6′ – 11 9/32″ |
| Height | 2′ – 11 3/32″ |
| Panel | Overall Frame |
| Qty | 1 unit / 7 panels |
| Width | 21′ – 3¾” |
| Height | 6′ – 3 1/16″ |
In-House Engineering, Drafting & Design
Installing a walkable skylight on a New York City townhouse rooftop in 2017 meant navigating one of the most demanding building department environments in the country. Our engineering team prepared the full technical package required for NYC plan review — project-specific stamped shop drawings, structural calculations, and energy compliance documentation covering the Series 2000 frame’s ICC-ES certification and the SkyFloor® Series 2000 system’s NFRC-rated thermal performance specifications, including U-value and SHGC values for NYC Energy Code compliance. The 7-panel, two-configuration layout was not a standard off-the-shelf dimension — our drafting team produced the custom fabrication drawings for the 5 standard panels and 2 extended panels that make up the 21′ 3¾” × 6′ 1 1/16″ overall assembly, ensuring each panel was sized to align precisely within the frame and with the surrounding terrace surface. The thermally broken Ensinger Insulbar® detail at the frame perimeter was specified and documented to prevent cold bridging in New York City’s four-season climate — a detail that matters as much to the city’s energy inspectors as it does to the homeowner. The result is a system that arrived on site fully engineered, fully documented, and ready for a clean, permittable installation.
“Awesome company-super happy with the product and service! ”
— Elliot Berkowitz, Owner/President, Riverside Builders, Google Review
Results & Impact
What Was Achieved
- Full natural daylight delivered to the living room and art gallery with zero loss of rooftop terrace space
- Flush, architecturally invisible installation — the SkyFloor® panels integrate seamlessly into the terrace deck
- Complete privacy is maintained for interior spaces via the Yorlux™ satin anti-slip surface—allowing diffuse light in while limiting visibility—and is tested to meet the ANSI A326.3 standard for wet and dry dynamic coefficient of friction performance.
- Dramatic nighttime effect — illuminated glass panels create a glowing terrace centerpiece
- Full structural compliance with NYC building code for pedestrian-loaded walkable glass
- ICC-ES certification and NYC energy code compliance ensured a smooth permitting and inspection process — no delays, no custom approval hurdles
- Thermal performance verified: U-value 0.32 / SHGC 0.27
Long-Term Value
Completed in 2017 and performing flawlessly since installation, this project demonstrates the capability of the SkyFloor® Series 2000 to solve architectural challenges that no conventional skylight product can address. It remains one of the most technically refined residential walkable skylight installations in New York City.
Project Team
- Glass System Design & Manufacturer: Glass Flooring Systems
- Architect: SPAN Architecture
- Installer: Riverside Builders
About Glass Flooring Systems
Glass Flooring Systems is the world’s leading expert in walkable glass — specializing in structural glass floors, walkable skylights, glass stairs, bridges, decks, and custom architectural glass for luxury residential and commercial projects. Our SkyFloor® Series 2000 is NFRC- and ICC-ES-certified, NYC energy code compliant, and carries the industry’s largest selection of ANSI A326.3 tested anti-slip textures. We set the benchmark for design, quality, safety, and performance in the walkable glass industry.