BREEAM New Construction (NC)BREEAM In-Use (BIU)
The main differenceIt is the process and the result of building design and construction that is being assessed.
To demonstrate compliance, project team has to conduct multiple calculations, carry out tests, analysis to check and prove that the most sustainable options (engineering systems, materials, etc.) have been selected for the building. Most of these works are carried out by third-party consultants who use BREEAM-suitable software. A New Construction project also requires more engagement from BREEAM assessor because he/she has to supervise how BREEAM NC requirements are being fulfilled throughout building design and construction stages.
It is the result of building construction that is being assessed.  
Such assessment requires much fewer calculations, tests, etc. compared to New Construction because majority of needed works can be done by building design or construction team, if they know the scope well in advance. BREEAM assessor is much less involved in the project because he/she assesses what’s in place after the building has been completed i.e., the result after building construction is completed.
BudgetFrom 30.000€/building, depending on desirable certification level and needed additional services (ordered from third parties).
From 5.000€/building; doesn’t depend on desirable certification level. Some of the needed calculations, tests can be done quite easily by building design team and construction team.
Duration2-5 months after the building is officially completed i.e., use permit is issued. This time is needed for BRE Global to review certification docs and for project team to address comments, if any1 week -3 months after the building is officially completed i.e., use permit is issued. Duration varies because some projects are selected by BRE Global for detail check of certification material
Validity of the certificateValid for a life-timeBIU certificate is valid for a 3-year period. After that it has to be renewed.
Pros• Comprehensive building assessment in multiple sustainability categories (energy, water, transport…)
• NC certificate is valid for building’s lifetime; it doesn’t require periodic renewal
• It’s a more appropriate certification option for a newly built object than BIU.
• NC certification is a great opportunity to select/check the optimal solutions will ensure building’s efficiency and sustainability throughout the whole life cycle.
• It engages all project participants and provides some sort of quality check and sustainability guidance during building design and construction stages.
• Comprehensive building assessment in multiple sustainability categories (energy, water, transport…)
• Lower certification costs
• Shorter certification duration and less impact on building design and construction processes because it’s the result that is being assessed. Therefore, it’s possible to prepare for this after-construction check in advance because teams known what will be assessed during the audit.
• The client and his team is much less involved into the process because the assessor completes most of the work. E.g., he/she collects necessary info from project documentation and carries out and extensive photo shooting to collect evidence for the audit.
• There is a possibility to demonstrate improvement, progress and achieve higher certification level during re-audits (required once every 3 years).
• Documents in Lithuanian language are suitable for the BIU certification.
Cons• Larger certification costs
• A greater engagement by project team and BREEAM assessor is required. However, BREEAM assessor ≠ technical supervision of construction process i.e., he/she supervises construction process to the extent needed to ensure that BREEAM requirements are fulfilled.
• Add. services from third parties (calculations, tests) are needed. This causes increase of project budget and also there is a need to sign agreements, supervise the works of these external parties, etc.
• Certification docs must be in English or translated to English. 
• The scope of NC documentation is much larger than BIU. It’s also required to monitor & collect data during construction process (utilities, waste amounts, product specifications, etc.)
It is necessary to choose BREEAM-compliant products & materials (certified wood, effective sanitary products, healthy building materials, etc.) rather than those preferred by the project team.
• BIU certificate requires periodic renewal and recertification. However, this provides an opportunity to demonstrate that building’s sustainable features are maintained and meet the high international requirements over time. Meanwhile, NC is a one-time certification and doesn’t guarantee that building will keep and maintain the inbuilt sustainable features.
BREEAM assessor joins project team before construction begins (with pre-assessment results and recommendations) and when construction process is about to be completed (when preparing for final audit and certification). During the construction process, the assessor is a passive participator and doesn’t interfere the works. However, at any point the project team can consult with the auditor about BIU requirements and how to correctly implement them.

This article is also available in Lithuanian.