AHURP Technique Focus : Insulation Efficiency

For the construction of 10,000 green housing units in Ulaanbaatar, Mongolia, the eco-district, named AHURP, aims to be low-carbon and climate resilient by optimizing the building design from a passive and active perspective. In order to achieve this goal one of the solutions to have been set up is highly efficient insulation. We will in this article explain why this technique is one of the major priorities for energy savings and efficiency.

Insulation definition:

Insulation in the construction sector is a key part of the process. In fact, good insulation limits the flow of energy between the exterior and interior, meaning it also limits the gain or loss of heat. In dry and marine zones, during the winter, the insulation will keep the interior heated while in summer it will limit the building from gaining heat from the exterior. In tropical zones, during all seasons it limits the gain of heat.

U-value meaning:

To fully understand the performance of insulation material, let us introduce the definition of « thermal conductivity ». In fact, it’s the measure of energy transferred across a known thickness of the material. In construction, we use the term U-value to calculate the amount of heat transmitted through a predefined area of a building. The unit is W.m-². K-1 (Watts per square Metre Kelvin).

This U-value is used to measure the efficiency of the insulation material. For your building insulation, the lower is the U-value, the slower heat will be transferred from one element to another and the better will be the efficiency of the insulation.

As a matter of fact, for sustainable buildings you need a low U-value for your insulation in order to reduce the amount of heat lost or gained and then reduce the consumption of energy needed for the building to be heated or air-conditioned. However, some materials are dangerous for the ecosystems and the health of the occupants.

Examples of environmentally friendly materials:

• Cellulose:

It’s made from plant fiber to insulate walls, roofs and walls. This solution is cheap and has a low U-value that makes it very efficient. Cellulose is also draught proof and fireproof and non-toxic for the building occupants. However, this solution can get wet due to condensation or leaks.

• Wood wool:

It’s made from wood slivers cut and is efficient for thermal and acoustic insulation. This solution is a durable and eco-friendly product because it is made from natural material. Wood wool is damp proof and vapor permeable.

• Sheep wool:

Sheep’s wool is a natural insulation material. This solution is sustainable and eco-friendly. For occupants, it doesn’t have an impact on their health and it’s also efficient for acoustic insulation and is fireproof.

• Cork:

Corkboard is created from the cork granules without additional chemical products. This solution has a great efficiency for thermal and acoustic insulation. This solution is a durable and eco-friendly product because it is made from natural material while being damp-proof. Moreover, it lasts very long. However, the price remains high.

• Hemp:

Hemp wool is made from woody fibers in hemp plants. This material has a high durability and sustainability because it is compostable while being a great insulator. Being completely recyclable this material is not adapted for damp spaces.

• Straw bale:

Straw is a natural material and with a great efficiency for thermal resistance. In fact, it’s biobased and compostable. However, this solution is often not fireproof and for being efficient the thickness needs to be high meaning you need to sacrifice space in your building.

For our project in AHURP we used a highly efficient solution for the insulation of the buildings in order to save energy and achieve the goal to only use renewable energy in this district. If you want to learn more about this huge project, you can consult our portfolio: https://www.greendesignconsulting.com/project-ahurp-ulaanbaatar