For a contractor that also runs operation and maintenance (O&M) contracts, the most expensive day in a project's life is often the one nobody plans for: the day the building is handed over to maintenance. Everything the O&M team needs to do its job — the assets, their serial numbers, the warranties, the manuals, the open snags — was created during construction. If it isn't handed over properly, the maintenance contract starts blind, the warranty claims are missed, and the first year's faults end up on the wrong budget.
This checklist covers what a construction-to-O&M handover should include, how to handle the defects liability period, and what a system needs to carry the information from one side of the business to the other.
Why the handover matters more when you do both
When a client takes over a building and hires a separate FM company, the handover is a contractual milestone with documents attached. When your own company builds it and then maintains it, the handover is often informal — the same people, the same client, "we know where everything is". That is exactly when information gets lost:
- The site team demobilises and takes its knowledge with it
- Supplier warranties sit in procurement folders, not in the maintenance system
- Snags raised at completion are never closed, or are closed twice
- Faults in the first year are paid for by the O&M contract when they were construction defects or warranty claims
The handover checklist
1. As-built asset register
Every maintainable asset installed on the project, with:
- Location (building, floor, room)
- Asset type and category
- Make, model, serial number
- Installation and commissioning dates
- The supplier or subcontractor who supplied and installed it
Build this during construction, not at the end — it is far easier to record a serial number when the equipment is delivered than to find it later behind a ceiling.
2. Warranties
For each asset or system:
- Warranty start date (usually commissioning or handover — check the supply contract)
- Warranty end date
- The supplier's contact for claims
- What the warranty covers and excludes
Warranty dates belong on the asset record itself, so a technician can see at the moment of a fault whether it should be claimed.
3. O&M manuals and certificates
- Operation and maintenance manuals per system
- Test and commissioning certificates
- As-built drawings
- Spare-parts lists recommended by manufacturers
- Any statutory inspection certificates required before operation
4. Open snags
Every snag still open at handover, with its location, the responsible subcontractor and a target date. Snags are construction obligations; they should not quietly become O&M work orders.
5. Initial PPM plan
Using the as-built register and the manufacturers' recommendations, the first planned preventive maintenance plan for the O&M contract — ready to run from day one.
6. Spares and stock
Spare parts handed over by suppliers or bought for the O&M contract, received into the maintenance store with quantities and locations.
7. Training records
Who on the O&M team was trained on which systems, and by whom.
The defects liability period
Most construction contracts include a defects liability period (DLP) after completion, during which the contractor must fix defects in its work. For a company that also holds the O&M contract, every fault in that period needs one question answered before anyone is sent to fix it: who pays?
- Caused by workmanship or installation — a construction defect, charged to the project as the contractor's cost
- A failure of equipment under warranty — a warranty claim, charged to the supplier
- Caused by use, wear or the client — an O&M call, charged to the O&M contract under its terms
Decide the classification rules in advance, apply them at the moment each fault is logged, and keep the evidence on the request: photos, the asset's warranty date, the technician's findings. At the end of the DLP, this record shows exactly what construction still owes and what was correctly charged to maintenance.
Running both divisions on one system
The handover works best when construction and O&M share one system, with each division keeping its own profit and loss:
- The project's assets become the O&M contract's asset register in one step, instead of being re-typed
- Warranty dates travel with each asset
- Faults during the DLP are logged against the asset and classified as defect, warranty or O&M
- Shared people, vehicles and equipment are charged to whichever side used them
- Management sees margin per project, per O&M contract and per division, every month
Questions to ask before your next handover
- Who owns the as-built asset register during construction, and where does it live?
- Are supplier warranty dates recorded per asset, or only in purchase files?
- How will faults during the defects period be classified, and by whom?
- Which open snags will exist at handover, and who closes them?
- Is the first PPM plan ready before the O&M contract starts?
Work with us: see how we build Odoo for construction and facility management companies — one system from the first BOQ to the last maintenance visit — or read how to build a PPM plan for an O&M contract.
FAQ
What is a defects liability period? A period after completion, set in the construction contract, during which the contractor must fix defects in its own work. Its length and conditions depend on the contract.
Who pays for faults during the defects liability period? It depends on the cause: workmanship defects are the contractor's cost, equipment failures under warranty are claimed from the supplier, and faults from use or wear fall under the O&M contract's terms.
When should the as-built asset register be built? During construction, as equipment is delivered and installed — not at handover, when much of it is already concealed.
Does the O&M team need its own copy of project documents? It needs the information attached to each asset — warranty, manual, serial number — rather than a separate archive. One shared system avoids keeping two versions.