Why Myanmar’s Ancient Pyatthat Roofs Still Keep Buildings Cool

If you walk through Mandalay, you’ll see them everywhere: tiered, pyramid-like roofs stacking upward in shrinking steps. In Myanmar, these are called Pyatthat. For over a thousand years, they have topped monasteries, palaces, and modern landmarks like Yangon City Hall.

These roofs were originally built to represent Buddhist cosmology, with each tier symbolising a plane of existence. But because they have survived centuries of tropical heat and humidity, researchers wanted to test if the shape actually keeps buildings comfortable.

I tested how these roofs handle heat.

• Article title: A review of traditional multistage roofs design and performance in vernacular buildings in Myanmar
• Published via: Sustainable Cities and Society, 60, (2020). 102240
• Project: PhD research at the University of Nottingham
• Authors: May Zune, Conrad Allan Jay Pantua, Lucelia Rodrigues, Mark Gillott
• Link (if SCS is not working): Google Drive

Testing the Design

Using digital thermal and airflow simulations, the researchers modelled three roof styles with identical indoor space:

1. A traditional three-stage Pyatthat roof.
2. A simpler one-stage tiered roof.
3. A basic single-gable roof.

They tested the designs against a full year of Mandalay weather, swapping out different materials, ceiling types, and ventilation options.

Ventilation Matters More Than Shape

The simulations showed that roof shape alone doesn’t guarantee comfort. The critical factor was ventilation—specifically whether hot air trapped under the tiers could escape through gable vents.

• Airflow: Proper roof ventilation improved annual indoor comfort by up to 3.5% over unventilated setups.
• Materials: Traditional thatch and timber cooled down quickly at night, but got hotter during peak daytime sun. Modern brick and metal roofing absorbed heat longer, which prevented drastic temperature spikes during the day but kept nights warmer.

The Heat Trap Inside the Roof

Down where people actually stand and live (up to 2.5 meters high), the multi-tiered roof kept indoor air 1°C to 2°C cooler than a basic gable roof.

However, the space inside the high roof tiers behaved differently:

• Without proper airflow, heat pooled inside the top of the roof, with simulated temperatures reaching near 56°C under extreme conditions.
• Over time, that trapped heat radiated back down into the living areas below.

Ancient builders left these high roof spaces empty for a reason. The gable vents at each tier junction act like chimneys, pulling hot air up and pushing it out of the building.

What We Can Learn Today

The geometry of a Pyatthat roof naturally creates vents and a strong chimney effect to exhaust hot air. This design helps block solar heat before it reaches the occupants inside.

As climate change drives regional temperatures higher, traditional passive cooling methods may not be enough on their own. However, modern architecture can still benefit from incorporating these core techniques: effective shading, strong exhaust paths for hot air, and smart material choices.