Building studies

Eco-design of building

The building sector is one of the most energy and natural resource consumer sector in the world, it represents almost the half of the world total consumption. This sector presents thus a high potential for energy and resource reduction.

My first work in the building area was to identify passive solutions can be used to improve the indoor comfort of a building used as a school. Then I work on the eco-design of a building using bio-sourced material.

The use of bi-sourced material is one of the potential solution to reduce the embodied energy of the building and the environmental impacts related to the production of material. Thermal insulator from hemp concrete is one of the material promoted to have a low environmental impacts. This material is also presented to have a good thermal insulation properties and a good hygric regulation behavior.

The hemp concrete is a highly porous material, we can localise three types of porosity in the hemp concrete material in the hemp shives particle, in the matrix binder and in the contact of both (Fig 1).

Fig 1. Porosity of the hemp concrete (Collet)

Hemp concrete properties, density, porosity, thermal conductivity depend then on the proportion of the different components on their arrangements and on the manufacture of the material. These properties are highly variable. In this first attempt, we try to quantify the effect of these material properties variation on a simple building made by a single layer wall composed of hemp concrete.

This work with the hemp concrete material concerns the eco-design of a simple building with the six walls, each composed of a single layer made by hemp concrete. The goal was the identification of technological solutions could be used to reduce the energy consumption used for maintaining the building in a comfortable condition.

Heat and mass transfer

We used a simple building model considering the heat and mass balance with a thermal regulation. For all wall we considered a one dimensional heat and mass transfer with a flow in the direction perpendicular to the wall. The model established by Kunzel was used to characterize these coupled transfer.

Actually, I am working on the perspective of the previous study in order to investigate a building with a multilayer wall and adding more variability related to the building inhabitant.