Why insulation matters

Created By RISC | 2 years ago

Last modified date : 2 years ago

Thailand is hot and humid almost all year. Buildings have to keep out the heat or depend heavily on air-conditioning. ​

The sun’s heat generally enters structures through heat transfer, in which hot air moves to cooler air. Heat gets into buildings in 3 ways: ​
• Conduction: through a static medium like a wall, roof, or floor
• Convection: like the wind delivering or removing heat ​
• Radiation: without a medium, such from the sun to the earth, traveling through space, the atmosphere, and our home to us

We can reduce heat infiltration by installing insulation. If we choose a heat-resistant material, the temperature inside the building will be comfortable. We can cut the cooling load for air conditioners by up to 40%, also reducing greenhouse gas emissions. Insulation can also counter condensation, which produces humidity and mold.

When examining the variables of keeping our home cool or comfortable indoors, the critical factor is decreasing heat transfer from outside. Good design takes account of the direction of the sun and the surroundings to keep homes cool. The building façade also plays a big role. Façade materials should limit heat transfer from the exterior to the interior. If we understand the heat transfer process, we can choose the best materials. Building façades can have 3 layers...

Exterior surface​
The first stage in reducing heat transfer into a building is the surface of the building façade:​
• Because stagnant air on the material surface has a high heat resistance, the surface material must reflect radiation well. ​
• It’s important to stop heat from flowing in the wrong direction, such as to the side of the wall or up or down from the roof. ​
• A low-wind surface area will keep the air stationary at the material's surface, raising heat resistance.

Material qualities ​
Heat transmission can be divided into 2 elements:
• Materials that reduce and slow heat transfer are based on 2 principles: 1) Materials with larger mass are better at absorbing and retaining heat, slowing heat transfer from heat transmission from one side to the other. 2) Materials with a narrow air gap and high porosity will reduce convective heat transfer, which we call "heat retardant" – aerated concrete materials and various types of insulating materials have this property.
• Material layering of building façades is the process of layering materials with an "air gap" until we reach the system’s total thermal resistance. Efficiency depends on the size of the gap and the type of air in the gap, whether flowing or stagnant, and heat radiation reflection.

Inner surface
The final phase in heat transmission from the outside is the inner surface of the building façade:
• A surface with high radiation reflectance can enhance heat resistance in the stagnant air on the surface.
• It’s important to prevent heat from flowing in the wrong direction, such as to the side of a wall or up or down the roof.

Plenty of products can give you a cooler home. Rather than relying on AC you can select effective and healthy insulation. Find out more at https://www.facebook.com/riscwellbeing/posts/2751256495137516

Story by: Dr. Sarigga Pongsuwan, Vice President of RISC