The challenge

Comparing local carbon data

The built environment is responsible for 37% of the total annual global CO2 exhaust. This includes the production of materials, construction, and operation of buildings and infrastructure. The production and transportation of materials like cement, steel, bricks, and glass are major contributors to greenhouse gas emissions.

In contrast, very little emissions data exists for locally sourced natural materials such as stones, soils, and timbers. This research aims to provide this missing data for common building typologies found in the Himalayan region.

Background

A Life Cycle Assessment (LCA) is a tool used to evaluate the environmental impact of all stages of a product's lifespan, from raw material extraction to disposal or recycling.

A carbon footprint, or embodied carbon assessment, is a subset of this process that specifically analyzes direct emissions of greenhouse gases like carbon and methane, which contribute to global warming.

What we need to do

Carbon footprinting is a relatively new concept in most developing countries, so local emissions data for building materials are often difficult to find or nonexistent. This research aims to bridge this gap by focusing on four earthquake-resistant construction typologies built by Smart Shelter Foundation in Nepal. They are:

• Rubble stone masonry with a timber roof
  
  

• Concrete block masonry with a steel roof
  
  

• Confined masonry with a concrete slab
  
  

• Reinforced concrete frame with a concrete slab

Our research approach

For a fair comparison, we've developed case study buildings of both schools and houses for all four typologies, ensuring they have similar heights and dimensions. The three-classroom schools are one story high, while the houses have two stories. The designs are common for the Himalayan region and include various earthquake-resistant features according to the current state-of-the-art, although some of these features are still under research.

We have created detailed bills of quantities that provide exact volumes, surfaces, and amounts of materials for each design. These estimates are broken down into five main construction stages: foundation, walls, roof, flooring, and finishing.

For all materials present in the designs, we aim to find the most recent and relevant carbon emissions data. If such data does not exist, we will use globally accepted databases. A representative village has been chosen in Nepal's Kaski District to determine the transportation routes and distances between the sites where natural materials are harvested, and the markets where manufactured building materials are purchased.

Results

The collected data allows us to compare the four typologies and determine the environmental impact of each school building. Our initial findings are striking: rubble stone masonry uses five times less steel, a massive reduction that highlights its environmental and economic benefits. This also comes with a 63% reduction in cement compared to a reinforced concrete frame building of the same size, further demonstrating its sustainability.

The final results will be internationally published in late 2025 or early 2026.

Get involved

We are specifically looking for emissions data for developing contexts, particularly for India and Nepal. This includes information on locally produced cement, steel profiles, galvanized steel sheets, bricks, concrete blocks, paints, and emissions from transportation and construction equipment. If you have access to such data or published papers, please get in touch to collaborate and exchange knowledge.