//How Much Carbon is Created When Building a House?

The construction industry is under increasing pressure to confront the carbon footprint of how we build in the drive towards Net Zero. This article breaks down the full carbon picture of housebuilding and explores how offsite timber frame construction offers a high-performance, low-carbon alternative to traditional masonry methods.

//Understanding Carbon in Construction

Embodied Carbon

Embodied carbon refers to the greenhouse gas emissions associated with the materials used to construct a building. It includes emissions from:

• Raw material extraction 
• Manufacturing and processing 
• Transportation to site 
• Construction and installation

Measured across life cycle stages A1 to A5 (as defined in EN 15978), embodied carbon is typically released before the building is even occupied. Embodied carbon can now represent around 30% of a standard building’s footprint and as much as 75% for an ultra-low energy building, depending on design and material choices.

As buildings become more energy-efficient, embodied carbon now accounts for a larger proportion of a home’s total lifetime emissions making it a critical area for intervention.

Operational Carbon

Operational carbon is the carbon dioxide emitted during a building’s use, primarily from heating, cooling, ventilation, lighting, and appliances. Traditionally, this dominates the carbon footprint, but new-build homes built to modern standards can dramatically reduce operational energy demand.

A combined approach that tackles both embodied and operational emissions is essential when looking to reduce the amount of carbon produced when building a house.

//The Carbon Breakdown of a Typical UK House

To understand the scale, let’s take a representative example—a medium scale residential home built compliantly with current Building Regulations over a 60-year lifespan. The total carbon footprint is composed of:

Operational carbon (B6) accounts for 67% of total carbon emissions.

Embodied carbon is distributed across stages:

• Products/materials (A1–A3): 21%
• Transport (A4): 1%
• Construction (A5): 2%
• Maintenance and replacements (B1–B5): 4%
• End of life (C1–C4): 1%

This baseline highlights where big carbon savings can be achieved, particularly in reducing upfront emissions through material and construction choices.

//Masonry/Steel vs Timber Frame

Embodied Carbon of Common Materials

Some of the most carbon-intensive materials in typical construction include:

• Concrete: 0.034–0.172kg CO₂e per kg 
• Steel: 1.55–2.46kg CO₂e per kg 
• Brick: 0.213–0.454kg CO₂e per standard brick 

By contrast, timber has an extremely low embodied carbon profile and stores carbon absorbed during the tree’s growth. While carbon accounting methods vary, responsibly sourced timber can act as a carbon sink, offsetting emissions elsewhere in the build.

For a timber frame system, this translates to significantly lower emissions at the structural level compared to masonry or steel equivalents.

Lifecycle Impacts

Timber not only offers immediate carbon savings but can also enhance circular economy outcomes at end-of-life. It is renewable, recyclable, and, when managed sustainably, contributes to forest regeneration and carbon drawdown.

Architects and housebuilders must consider durability, moisture protection, and fire performance but modern timber frame systems meet or exceed all required standards with proper detailing.

//Carbon Advantage of Offsite Timber Frame Construction

Offsite manufacturing amplifies the benefits of timber by improving efficiency, reducing waste, and streamlining logistics.

Reduced Embodied Carbon

Offsite construction allows for precise material usage, significantly reducing waste at the manufacturing stage. For example, timber offcuts can be reused or recycled in a controlled factory environment. Using these materials in panel production also means lower overall demand for high-carbon materials like concrete and steel.

Efficient On-Site Assembly

Because timber frame components are delivered to site prefabricated, on-site construction time is significantly reduced. This leads to:

• Less factory usage and associated fuel consumption 
• Fewer deliveries to site, reducing transportation emissions 
• Less energy required for temporary services (heating, lighting, drying)

These benefits contribute to lower A5 emissions and help housebuilders meet tight construction schedules while reducing environmental impact.

Fabric Efficiency & Performance

Offsite-manufactured timber frames deliver consistent quality and airtightness, supporting high thermal performance. This has a direct impact on operational carbon:

• Reduced space heating demand 
• Easier integration of insulation and renewables 
• Supports compliance with Net Zero standards 

A well-insulated, airtight envelope reduces heating energy use which leads to substantial long-term carbon savings.

//How to Reduce Carbon When Building a House

Know your carbon baseline: Understanding how carbon is distributed across materials, transport, and site activity is essential for making informed decisions.

Optimise early: The biggest carbon savings come from material and method choices made at the design stage, so timber frame and offsite methods should be considered.

Partner with experts: Timber frame manufacturers like Pinewood Structures can help integrate low-carbon strategies into the design and construction process from the outset.

Deliver on client and regulatory goals: As Net Zero homes become the expectation, not the exception, efficient low-carbon systems will be critical to maintaining competitive advantage.