BREEAM is the world's leading sustainability assessment method for buildings, developed by BRE in the UK. It assesses environmental performance across 10 categories and awards ratings from Pass to Outstanding. Over 590,000 buildings have been BREEAM certified worldwide.

What are the BREEAM ratings?

Pass: 30%+. Good: 45%+. Very Good: 55%+. Excellent: 70%+. Outstanding: 85%+. Many local authorities require BREEAM Excellent for major developments, and some specify Outstanding for public buildings.

Which categories carry the most weight?

Energy (19%), Health & Wellbeing (15%), Materials (12.5%), Management (12%), and Ecology (10%) carry the most weight in BREEAM New Construction. Focusing on these high-weighted categories gives the best return on investment for achieving higher ratings.

What are mandatory credits?

BREEAM requires certain minimum credits to be achieved for each rating level. For Excellent, these include minimum energy performance, water monitoring, construction waste management, and sustainable transport assessment. Missing a mandatory credit can prevent achieving the target rating.

How much does BREEAM certification cost?

BREEAM assessor fees range from £5,000-£25,000 depending on project size and complexity. BRE registration fees are additional. The cost of achieving credits varies - some (like management processes) are low cost, while others (like enhanced energy performance) require significant investment.

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BREEAM Credits Estimator

Estimate your BREEAM score from design choices and specifications

Building Type

Energy Reduction vs Part L

Water Reduction vs Baseline

How We Calculate This

Enter percentage scores for each BREEAM category based on the credits you expect to achieve. Energy and water categories convert your % reduction targets into credit estimates. Each category score is multiplied by the BREEAM weighting factor and summed to give the overall weighted score. The corresponding BREEAM rating (Pass to Outstanding) is then determined.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.