When the doors of the old garment factory in Katunayake swung open after its EnerPHit retrofit, workers felt an almost tangible shift: the air was cooler, the daylight gentler, and the atmosphere decidedly more uplifting. What had once been a noisy, fiber-filled shed was reborn as a world-class innovation center—proving that in Sri Lanka’s tropical monsoon climate, Passive House principles can deliver both human comfort and dramatic energy savings.
Walking through the low-rise industrial park just outside Colombo, you’d be forgiven for expecting yet another gray, metal-clad factory. Instead, you’re greeted by a clean-lined silhouette, its reflective roof glinting in the sun and a delicate perforated screen filtering light at the glazing line. Inside, designers, engineers, and machinists share one open workspace — naturally ventilated at the periphery, air-conditioned at the core — allowing collaboration to flourish under one roof.
The decision to renovate rather than rebuild was as much about stewardship as it was about cost. By stripping the building down to its existing steel skeleton and concrete slab, the team avoided the waste and embodied carbon of demolition. Yet this posed a question: how do you turn a decades‐old industrial shell—optimized for high-speed manufacturing—into a finely tuned, airtight, and highly insulated Passive House building in a place where triple-glazed windows and specialized insulation don’t exist locally?
Bridging Climate, Culture, and Construction
Sri Lanka’s steady 28–32 °C temperatures and punishing humidity would overwhelm conventional retrofit approaches. To succeed, the team wove together low-tech details with cutting-edge materials:
- Liquid-applied air barriers on masonry walls, followed by foam insulation and stucco, created a continuous envelope without relying on unfamiliar trades.
- Insulated roof sandwich panels, factory-assembled and engineered for moisture protection, snapped into place over the old shed, transforming the once-hot ceiling into a temperate surface.
- High-performance windows, shipped in from Europe, were set back beneath deep overhangs and paired with a fixed, perforated shading skin—cutting solar heat gain while bathing the interior in soft, diffused daylight.
Training local contractors became part of the solution. Mock-ups of critical details, on-site workshops for airtightness tapes, and step-by-step commissioning guidelines enabled a smooth transfer of Passive House know-how. By project end, the site team could test airtightness themselves—documents show they achieved an envelope leakage of just 0.76 ACH50, comfortably surpassing the EnerPHit benchmark.
The project is the first Passive House project in South Asia, and one of only two certified factories in the world.
From Data to Daily Impact
Remote monitoring systems now feed real-time energy data back to the design office, confirming that theory matches reality. Over the past year the Center has:
- Cut total energy use by more than 70% compared to a typical “efficient” factory.
- Slashed humidity-control costs, saving over US $8,000 per year on dehumidification alone.
- Maintained a steady 24 °C ±1 °C indoor temperature, with relative humidity never climbing above 60%—even at the height of the monsoon.
For the garment operators, these aren’t just numbers; they translate into fresher air, quieter machines, and daylight-filled workstations that reduce eye strain and boost morale. The retrofit’s projected payback—well within its ten-year target—cements the case that sustainable design and economic sense can go hand in hand.
A Blueprint for Tropical Retrofits
More than a singular achievement, the Star Garments Innovation Center has become a living prototype for comparable facilities across South Asia by demonstrating that an outdated factory can be revitalized into a Passive House with minimal new foundations, local materials, and a focus on simple detailing.
With Sri Lanka’s textile industry at a crossroads — facing rising costs, tightening environmental standards, and calls for ethical manufacturing — the EnerPHit approach offers a powerful solution, proving that tropical Passive Houses aren’t just possible, but profitable.
As the Star Garment Center continues to hum with activity, it stands not only as Sri Lanka’s first certified Passive House, but as a beacon for a more sustainable, human-centered future in global manufacturing.
Resources:
https://circular.cx/projects/star-garment-innovation-center
https://www.passivhausph.org/event-details/project-spotlight-passive-house-in-very-hot-climate
https://passivehouse-database.org/index.php?lang=en#d_6030
Project Team
DESIGN TEAM
Jordan Parnass
Marijke Huelsmann
Kevin Hennessey
Philip Weller
Yereem Park
CONTRACTORS
Tritech Engineering
Civicon Engineering
Alufab PLC
CONSULTANTS
Lead Architect & Interior Design – Vinod Jayasinghe Associates (Pvt) Ltd (Sri Lanka)
PH & Energy Consultants – Steven Winter Associates
Mechanical Engineering – Chandana Dalugoda Consultants
Structural Engineering – Ajith Vandebona PE
Quantity Surveying – PrasadJasinghe, VFORM Consultants
MEP Engineering – Kosala Kamburadeniya PE
Certification – DragosArnautu, Passive House Institute
PHOTOGRAPHER
Ganidu Balasuriya
Circular
SUPPLIERS
Gutman – Windows & Doors
