01. Site Survey & Client Requirements
The existing lightwell is a long, narrow rooftop opening inside a dense Vietnamese townhouse. Field measurements showed that the opening is slightly tapered rather than perfectly rectangular, so the skylight had to be custom-fabricated to the as-built geometry.
- As-built geometry: clear length approximately 7,760-7,820 mm with transverse clear width varying from about 685 mm to 770 mm.
- Heat accumulation: the vertical shaft traps hot air from the lower floors, creating a strong need for high-level exhaust ventilation.
- Monsoon exposure: the uncovered lightwell allowed heavy tropical rain to enter the shaft and lower interior levels.
- Dense urban constraints: adjoining party walls left little working space and required a narrow custom sub-frame.
- Automated operation: the owner required powered opening, wall control and backup operation during power interruptions.
02. Conceptual Design & 3D Modelling
SUNRAY developed a four-bay linear skylight in which each glazed sash hinges along the upper edge and projects outward toward the party wall.
2.1 Four-Bay Top-Hung Ventilation Layout
The 7.77 m opening is divided into four independently actuated sashes, creating multiple high-level exhaust points across the lightwell rather than one oversized moving panel.
2.2 Rain-Screen Ventilation Geometry
When partially opened, the outward-projecting top-hung sashes act as glass canopies, supporting natural ventilation while helping shield the opening from light rain.
2.3 Perimeter Drainage Curb
The perimeter aluminum curb incorporates raised water barriers and flashing interfaces to move rainwater away from the sash rebates and toward the roof drainage path.
03. Shop Drawings & Electrical Specifications
Approved bilingual production drawings translated the tapered site measurements into manufacturing dimensions and defined the actuator, wiring and backup-power layout.
3.1 Structural & Dimensional Layout
- Overall sub-frame length: 7,777.2 mm
- Nominal clear opening: 7,760 mm
- Frame width / clear aperture: approximately 787 mm / 685 mm at the documented section
- Primary framing: 80 × 80 mm aluminum box sections
- Outer flank sash widths: 2 × 1,936.8 mm
- Center sash widths: 2 × 1,951.8 mm
- Actuator / hinge center pitch: approximately 1,921.8 mm
3.2 Electrical & Control Architecture
- Dual chain actuators per sash: 8 motors total
- Main input: AC 220V via BVV 2×2.5 mm² wiring
- Dedicated actuator control wiring: BVV 2×1.5 mm²
- Two wall-mounted control stations at approximately 1.4 m above finished floor
- Dedicated backup battery power unit: approximately 315 × 163 × 100 mm
04. Precision Manufacturing & Factory Quality Control
Manufacturing focused on dimensional accuracy, rigid welded frame geometry, durable architectural finishing and safe laminated glazing for tropical outdoor exposure.
4.1 80 × 80 mm Structural Frame Fabrication
The perimeter curb and sash frames were produced from aluminum profiles, miter-cut and assembled to the project-specific tapered geometry.
4.2 Dark-Bronze Fluorocarbon Finish
Visible aluminum components received the dark-bronze fluorocarbon finish specified in the source case study for tropical UV, humidity and urban exposure.
4.3 Laminated Glass Fitting
Each sash was prepared for 5 + 0.76 PVB + 5 mm laminated safety glass before factory testing.
05. 1:1 Factory Trial Pre-Assembly & Kinematic Commissioning
Before shipment, SUNRAY completed a full-scale trial assembly of the top-hung sashes on factory test benches.
5.1 Chain Actuator Synchronization
- Dual actuators on each sash were synchronized for stable opening movement.
- Opening angles up to approximately 45° were tested according to the source case study.
- Electronic open / close limit positions were checked.
- Backup-power transfer was tested under a simulated main-power interruption.
5.2 Weather-Seal Verification
Continuous EPDM perimeter gaskets were inspected for even compression and sealing around the sash rebates.
06. Export Packaging & Electrical Accessories
After testing, the structural components, actuators and electronic accessories were separated, labeled and protected for cross-border transport to Vietnam.
6.1 Frame & Profile Protection
Dark-bronze frame components were cushioned with pearl-cotton foam and protective stretch wrap before packing.
6.2 Controls, Manuals & Backup Power
- Pre-labeled control switches and wiring connectors were organized in dedicated accessory packaging.
- Digital installation files, wiring diagrams and operating materials were supplied with the project accessories.
- The backup power unit was packed separately with shock-absorbing protection.
07. On-Site Installation & Rooftop Commissioning
At the townhouse, the prefabricated skylight system was installed onto the reinforced-concrete parapet curb and commissioned under local site supervision.
7.1 Sub-Frame Anchoring & Waterproofing
The aluminum curb was aligned to the long tapered opening, mechanically anchored and integrated with perimeter waterproofing and flashing at the party-wall interfaces.
7.2 Sash Hanging & Actuator Installation
The four pre-glazed sashes were mounted along the top hinge line, followed by installation of the eight chain actuators between the curb and moving frames.
7.3 Electrical Commissioning
The two wall controls were connected to the AC 220V supply and backup battery system, followed by travel-limit and synchronized operation checks.
08. Final Handover & Residential Use
The completed skylight was handed over as an operable daylight and ventilation roof for the townhouse lightwell.
- Natural stack ventilation: opening the high-level sashes allows hot air to exhaust from the vertical shaft.
- Rain-screen operation: the top-hung geometry can support partial ventilation during light rain, subject to weather conditions.
- Backup operation: the dedicated battery unit supports powered closing during a main-power outage.
- Daylight improvement: laminated glass introduces natural light into the stairwell and interior lightwell.
- Architectural integration: the narrow dark-bronze frame system fits the dense urban townhouse geometry.