Commissioning, Soft Landings and O&M Clauses That Actually Get Delivered

How do commissioning, soft landings and O&M connect?

Regulation 44 requires a commissioning notice, soft landings sets the process from briefing to aftercare, and the O&M manual records the result. The specification turns each into deliverables, dates and payment links.

Commissioning, soft landings and the O&M manual are three views of one obligation: the building must work as designed and the people who run it must be able to keep it that way. In England, the legal hook is regulation 44 of the Building Regulations 2010, which requires a commissioning notice for fixed building services. The specification is where that duty becomes deliverables, dates and money.

Regulation 44 applies to building work under Requirement F1(2) or L1(b). The person carrying out the work must give the building control authority a notice that the fixed building services have been commissioned in accordance with a procedure approved by the Secretary of State. The notice is due no later than the date of the regulation 16(4) notice, or within 30 days of completion where that does not apply. For higher-risk building work with a completion certificate application, the notice goes to the regulator with the application. Related duties include regulation 40, which requires information on fuel and power to be given to the owner within 5 days of completion, and regulation 38 on fire safety information. Regulation 40C, a Home User Guide duty, is new from SI 2026/335.

Soft landings is the process view. The BSRIA Soft Landings Framework (BG 54/2018) has six phases: inception and briefing, design, construction, pre-handover, initial aftercare, and extended aftercare with post-occupancy evaluation. Government Soft Landings (GSL) is aligned with BS 8536-1 (briefing for design and construction, facilities management) and BS 8536-2. Check the current editions of both standards. The Construction Playbook says a proportionate GSL approach, supported by the UK BIM Framework, should be applied to all design and construction projects, so check the latest edition of the Playbook.

The specification is therefore not only a technical document. It carries the dates, deliverables and payment links that make commissioning and handover happen. See the guide to writing an M&E specification for where these clauses sit.

Which commissioning standards should the specification name?

Name the CIBSE Commissioning Codes by letter and title with the current edition, add the dwelling heat pump checklists where relevant, and confirm the approved procedure for regulation 44.

Name the CIBSE Commissioning Codes by letter and title, cite the current edition rather than a year, and add the project-specific standards for the systems in the building. The codes set out what commissioning should cover, the methods, and the records, so a specification that calls them up can ask for the output without writing the method.

The Approved Document L Volume 1 for dwellings names the MIS 3005-I:2025 Appendix A and the HPA heat pump commissioning checklists (paragraphs 7.10 to 7.14), which should be named alongside the CIBSE codes for dwelling heat pumps: see the Part L 2026 guide for services engineers. Fire alarm commissioning and certification follow BS 5839-1: see the fire alarm specification guide.

Regulation 44 refers to a procedure approved by the Secretary of State. The approved procedure for a project should be confirmed from the current Approved Document at the time the clause is written.

What makes a commissioning clause deliverable?

A clause that names a deliverable, a date, a witness and a consequence is delivered. Link retention to accepted records, and write seasonal commissioning into the aftercare period.

A commissioning clause is delivered when it names a deliverable, a date, a witness and a consequence. Clauses that say "commission all systems in accordance with good practice" produce a certificate at best. Clauses that say what must be issued, when, to whom and what happens without it produce records.

Two practical points sit behind that wording. First, seasonal commissioning only happens if it is written into the aftercare period, because the contractor has usually left the site by then. Second, retention is the lever that makes O&M quality a priority: tie it to accepted records, not to the delivery of a binder. Both are practitioner advice rather than standard text. Check them against the contract form in use.

Commissioning change control matters too. A substitution that changes system performance needs the commissioning plan updated, so it should run through the same process as other specification changes: see the guide to specification change control.

What should the O&M manual and building log book contain?

The O&M manual should hold system descriptions, drawings, schedules, operating and maintenance instructions, records and certificates, with TM31 as a log book basis and the CDM file coordinated.

An O&M manual should describe each system as installed, how to operate it, how to maintain it and what to do when it fails. A building log book is the shorter, operational record for the people running the building. The CDM health and safety file is related but separate, and the specification should say how the three relate.

CIBSE TM31 (Building Log Book Toolkit, 2006) is the commonly used basis for the log book. The O&M manual contents are set by the specification, because no one else will set them. The checklist below is a starting point, and the project should add to it.

Fire alarm

The logbook, certificates, cause and effect matrix and zone plan are BS 5839-1 deliverables, and they belong in the manual or file as a set.

Overheating

The model assumptions, the MVHR bypass operation and the staying cool advice belong in the O&M and the Home User Guide.

Controls

Control strategy, set points and schedules as commissioned, so the aftercare team can tell a fault from a change.

CDM

Information the principal designer needs for the health and safety file, issued as a coordinated set.

A draft manual should be reviewed before practical completion, not after it, and the specification should say so. See the pre-issue technical review checklist for the review habit, which applies equally to the manual.

How do soft landings and the golden thread fit together?

Aftercare needs a named team, duration and funding in the specification. For higher-risk buildings, commissioning records support the completion application and the golden thread.

Soft landings works when someone is given the time and money to do it, and the specification is where that happens. The aftercare phases need a named team, a duration, a fee or a retention link, and a reporting format. Without them, handover is the end of the project and the building is left to run itself.

Write the soft landings roles and the aftercare period into the preliminaries and the services sections. Include a post-handover visit programme, seasonal commissioning, a review of energy use against the design prediction and a feedback report, with a defined point at which the contractor and designer hand responsibility to the facilities team. The extended aftercare and post-occupancy evaluation phases are the least often funded, so decide at the start whether they are in scope.

For higher-risk buildings, commissioning and handover records are part of the golden thread. The regulation 44 notice goes to the regulator with the completion certificate application, so the commissioning records need to be in order before that application. See the golden thread guide for building services, the Avoice golden thread guide and the higher-risk buildings guide.

Holding the O&M and commissioning records as a project record from the start, with each item linked to the specification clause that required it, makes the completion submission a collation task rather than a hunt for documents.

Questions engineers ask about commissioning and O&M

What does regulation 44 require?

Regulation 44 of the Building Regulations 2010 requires the person carrying out the work to give the building control authority a notice that fixed building services have been commissioned in accordance with a procedure approved by the Secretary of State. It applies to work under Requirement F1(2) or L1(b).

When is the commissioning notice due?

The notice is due no later than the date of the regulation 16(4) notice, or within 30 days of completion where that does not apply. For higher-risk building work with a completion certificate application, the notice goes to the regulator with the application.

What are the phases of soft landings?

The BSRIA Soft Landings Framework BG 54/2018 has six phases: inception and briefing, design, construction, pre-handover, initial aftercare, and extended aftercare with post-occupancy evaluation.

Which CIBSE Commissioning Codes exist?

CIBSE publishes codes for air distribution systems (A), boilers (B), automatic controls (C), lighting (L), management (M), refrigeration (R) and water distribution systems (W). Cite the current edition in the specification.

What should an O&M manual contain?

It should contain system descriptions as installed, drawings, equipment schedules, operating and maintenance instructions, commissioning records and certificates, spares information and health and safety information for maintenance. The specification should list the contents.

How can the specification make seasonal commissioning happen?

Write it into the aftercare period with a return visit, a reporting format and a link to retention or fee, because the contractor has usually left site by the time seasonal conditions arrive.

Where Avoice fits

Commissioning and O&M clauses fail in the gap between a clear intention and a missing deliverable: a witnessing point nobody scheduled, a manual no one reviewed, a seasonal visit nobody funded.

Avoice writes building services specifications alongside architectural ones, so commissioning and O&M clauses can sit in the same specification as the systems they cover. The office master holds the practice's commissioning, witnessing and O&M clauses as a governed library, and practice rules can enforce required wording, for example that a standard is cited at its current edition. Avoice MEP and structural specifications are structured to CAWS or Uniclass 2015, the same as architectural specifications.

Construction Admin tracks submittals, RFIs and specification changes, which is where O&M and commissioning records arrive. The Compliance module and Project Record hold golden thread information for higher-risk buildings, so handover records can be linked to the clause that required them. Software retrieves, compares and flags. The engineer decides the commissioning strategy and the acceptance of records.