What is the BREEAM rating system and should I get my home certified?

The BREEAM rating system (Building Research Establishment Environmental Assessment Method) is the world's longest-established method for assessing, rating, and certifying the sustainability of buildings. Launched in 1990 in the UK, it has become a global standard for green building, influencing design and construction across 89 countries.

The reason green home rating systems such as BREEAM, LEED, Passive House and others exist, is to push the standard of buildings we construct beyond the basic requirements of code, which do not at all reflect the urgency to build homes better suited to face a changing climate. 

It is easy to think some great thought went into determining the R-values and airtightness of building codes, but that is far from the truth. In most regions, the R-value requirements of code are far below any sensible standard.

That's because they were never intended as a performance standard to shoot for, they are a minimum you aren't allowed to fall below. But its all we know, because housing developers build that way to keep costs down in an effort to maximise profits. So don't think of building code R-value standards as a target to shoot for, think of it more like a backstop behind the target for those with bad aim. 

Different rating systems are often more popular in certain areas that others, but that doesn't mean they don't serve a broader area. BREEAM is just such a standard - while it is most popular in the UK and Europe, it has a foothold in 100 other countries.

This page is intended to help you learn what BREEAM is about and decide if its the rating system that covers the design criteria that is important to you. Here is what we will cover in case you want to skip ahead:

  1. Understanding BREEAM: history and purpose
  2. How BREEAM certification works
  3. The assessment categories
  4. Scoring, stars, and classification
  5. BREEAM vs. LEED: what is the difference?
  6. The certification process step-by-step

Understanding BREEAM: history and purpose

BREEAM stands for the Building Research Establishment Environmental Assessment Method. It was developed by the Building Research Establishment (BRE), a former UK government laboratory that is now a private non-profit organization. While it originated in the UK, the standard has been adapted for international use, including specific schemes for the US, Europe, and the Gulf region.

The primary purpose of BREEAM is to measure the environmental performance of buildings and infrastructure. Unlike local building codes that set minimum legal requirements, BREEAM sets best practice standards that go beyond the basics.

It encourages designers, architects, and builders to innovate in areas such as employing low embodied carbon construction techniques, biodiversity protection, and maintaining healthy indoor air quality in homes.

How BREEAM certification works

BREEAM is a holistic assessment method. This means it doesn't just look at one aspect of a building, like energy efficiency, but evaluates the project across a broad range of environmental and social impacts. The system is flexible and can be applied to:

  • New construction: For new homes, commercial buildings, and communities.
  • Refurbishment and fit-out: For major renovations of existing structures.
  • In-use: For assessing the operational performance of existing buildings (popular with facility managers).

To get certified, a project must be assessed by a licensed BREEAM Assessor. This is a key distinction from some other systems; you cannot simply submit your own evidence. An independent expert must verify that the building meets the rigorous criteria set out in the technical standards.

The assessment categories

The BREEAM standard evaluates a building based on its performance in several distinct categories. Each category is weighted differently depending on the project type and location, but they generally include the following:

Energy

This is often the most heavily weighted category. It measures the operational energy efficiency of the building, encouraging the use of home renewable energy systems and the reduction of carbon emissions. 

Health and wellbeing

This category focuses on the comfort and health of the occupants. It assesses factors like indoor air quality, thermal comfort, acoustic performance, and access to natural daylight.

Materials

BREEAM encourages the use of materials with a low environmental impact. This includes sourcing materials responsibly (e.g., FSC-certified timber) and using products with low embodied carbon. For comparison, you can see how the  LEED for Homes rating system also prioritizes material selection.

Water

This section assesses water efficiency, encouraging the installation of low-flow showerheads and fixtures, early warning leak detection systems, and water recycling methods.

Construction waste management

Scores are awarded for reducing and responsibly disposing of construction waste, and providing adequate facilities for operational recycling and waste management.

Land use and ecology

This encourages building on previously developed land (brownfield sites) rather than greenfield sites. It also rewards projects that protect and enhance local biodiversity.

Pollution

This covers the prevention of air and water pollution, including minimizing light pollution and reducing noise impacts.

Access to public transportation

Credits are gained for locating buildings near public transport networks and providing facilities for cyclists, reducing the reliance on private cars.

Sustainability management

This category ensures that sustainable practices are adopted throughout the design, construction, and commissioning phases, ensuring the building operates as intended.

BREEAM performance certification categories
 

Scoring, stars, and classification

Once the assessor has evaluated the building against the categories above, the credits are added up and weighted to produce a final percentage score. This percentage determines the BREEAM rating. The thresholds are as follows:

Rating Score Required Star Rating
Unclassified < 30% -
Pass ≥ 30% ★
Good ≥ 45% ★★
Very Good ≥ 55% ★★★
Excellent ≥ 70% ★★★★
Outstanding ≥ 85% ★★★★★

Achieving an Outstanding rating is incredibly difficult and represents the pinnacle of sustainable building innovation, often requiring a score within the top 1% of UK new non-domestic buildings.

BREEAM vs. LEED: what is the difference?

Homeowners and professionals often ask for the difference between BREEAM and the LEED for Homes rating system (Leadership in Energy and Environmental Design). While both share the goal of promoting green buildings, their approaches differ significantly.

Origin and dominance

BREEAM originated in the UK and is dominant in Europe, while LEED was developed by the US Green Building Council (USGBC) and is the dominant system in North America  (and the CaGBC in Canada). However, both sytems certify buildings globally.

Assessment method

The most critical practical difference is the assessment process. BREEAM requires a licensed assessor to evaluate the evidence and report to the certifying body (BRE). In contrast, LEED relies on the design team to collect and submit documentation to the Green Business Certification Inc. (GBCI) for review. This can make BREEAM feel more academic and rigorous, while LEED is sometimes viewed as more flexible for the project team.

Prerequisites and flexibility

LEED has mandatory prerequisites that must be met before you can earn any points. If you fail a prerequisite, you cannot be certified. BREEAM is generally more flexible; while it has minimum standards for higher ratings, it allows for more trade-offs between categories to achieve a "Pass" or "Good" rating.

The certification process step-by-step

If you decide to pursue BREEAM certification for a residential or commercial project, the workflow generally follows these steps:

  1. Pre-assessment: Engage a licensed BREEAM Assessor early in the design stage (RIBA Stage 1 or 2). They will help set targets and determine which rating is achievable.
  2. Design stage assessment: As the design progresses, the assessor collates evidence (drawings, specifications, commitments) and submits a report to BRE. If successful, you receive an Interim Certificate.
  3. Construction: The building is constructed. The assessor monitors progress to ensure the design commitments are actually met on-site.
  4. Post-construction review: Once the building is complete, the assessor verifies the final "as-built" evidence.
  5. Final certification: The final report is submitted to BRE for quality assurance. Upon approval, the Final BREEAM Certificate is issued.

In brief

The BREEAM rating system offers a robust, scientifically based framework for measuring sustainability. It pushes builders to go beyond code compliance, resulting in buildings that are healthier to live in, cheaper to run, and better for the planet. While the process is rigorous and requires a licensed assessor, the resulting certification significantly enhances the asset value and marketability of a property.

Now that you know more about the BREEAM rating system, find more info about LEED & green building techniques in the Ecohome Green Building Guide and these pages below:

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