The site logbook in Chile: what the OGUC requires and who signs each entry
Last reviewed: Regulations change: the text is checked against the official source at each review.
In Chile the libro de obras is a numbered-page document that forms part of the official project file and is kept on site throughout construction. In it are recorded the instructions and observations issued by the competent professionals, the authorised installers, the technical inspector, the independent reviewer where applicable, and the inspectors from the Municipal Works Department or from the bodies that authorise the services.
Its basis is article 143 of the General Urban Planning and Construction Act and article 1.2.7 of the General Ordinance. It is a compulsory requirement when applying for Final Acceptance of the works.
That last sentence is worth carrying from day one: without a logbook in order there is no final acceptance. It is not a formality you settle at closeout.
Who is responsible
From the start of the works, the builder in charge must keep the logbook on site, and both the builder and the technical inspector must sign it when construction work begins. The logbook, together with the quality management and control measures, must be presented to the Municipal Works Department at the time of acceptance.
Keeping it up to date is the builder’s responsibility. And updating it is neither optional nor periodic: the document must be kept permanently on every project and must be updated as the various items of construction are executed.
What the cover page must carry
Every logbook must contain on its cover, as a minimum: identification of the project with address, roll number and project type; number and date of the municipal permit; name of the owner; name of the architect; name of the structural engineer; name of the supervisor; name of the builder in charge once work begins; name of the technical inspector if there is one; name of the independent reviewer if there is one; name of the reviewer of the structural design where their appointment is required; and the names of the professionals designing the domestic services, urban works or specialist installations as those works begin.
That is more information than most logbooks carry, and municipal works departments do check it. It pays to assemble the full cover at the start rather than in a rush before acceptance.
Formal rules that get overlooked
Four points that appear in municipal guidance and that draw observations:
Consecutive volumes. If a new volume is needed to continue the entries, each volume must be numbered consecutively.
Closing note. The logbook must carry a closing note at the end, including names and signatures.
A signature on every entry. Each entry carries the signature of the professional making it, and the date.
Change of professionals. If during the works the owner or any of the competent professionals changes, that must be recorded in the logbook, without prejudice to whatever procedure applies.
That last one is the most forgotten. A change of builder or of structural engineer with no record in the logbook leaves a discontinuity the Works Department will pick up.
Who may write in it
The list is wider than many assume: the project’s competent professionals, the authorised installers, the technical inspector, the independent reviewer where applicable, and the inspectors from the Municipal Works Department or from the bodies that authorise the services.
That makes the Chilean logbook something other than a bilateral contractor-client instrument. It is a document of the official file where several figures with their own responsibilities converge, and each answers for what they write.
The structural engineer, in particular, has a specific duty: to assist the builder so that structures are executed in accordance with the drawings and technical specifications of the permit, recording that in the logbook.
The technical inspector
The ITO deserves attention because the role carries legal consequences many underestimate.
They are responsible for checking that the works are executed in accordance with the applicable construction standards and the approved building permit. Technical inspectors may be natural or legal persons providing that supervision service, exercised by or with competent professionals, independent from the builder.
And the point that defines the relationship: technical inspectors are subsidiarily liable alongside the builder.
That subsidiary liability explains the ITO’s behaviour on site. They are not being unusually strict by temperament: they answer with their professional standing for what gets built. The logbook is where they record their instructions and observations, and where they evidence that they did their job.
For the builder the practical implication is direct: an ITO observation recorded and not addressed is evidence against you, and an instruction complied with but with no record of that compliance evidences nothing.
Digital format
The digital logbook is dealt with in article 1.4.27 of the OGUC. The existence of specific regulatory treatment matters: it means digitisation is not an interpretation but a route the rules foresee.
The attributes a digital format has to preserve are the same ones that make the paper version valid: numbered pages, dated entries, an attributable signature from whoever writes, no way to alter without a trace, and permanent availability on site.
Frequently asked questions
- What happens if the logbook is incomplete when final acceptance is requested?
- The Works Department may raise observations and acceptance is delayed until they are resolved. Since a logbook cannot be reconstructed backwards without it showing, this is a hard situation to get out of.
- Does the logbook apply to every project?
- It applies to works that require a building permit, with the scope the regulation itself establishes. Check your specific case with the relevant Works Department.
- Can I keep the logbook at the office rather than on site?
- No. The requirement is that it be kept on site, permanently, so that everyone entitled to write in it can do so. A logbook that lives in the office does not do its job.
- What is the difference between the libro de obras and the contract communications book?
- The libro de obras is a regulatory requirement tied to the building permit and to municipal acceptance. Many contracts, especially public ones or those with institutional clients, also set up their own instrument for communication between the parties. They coexist and serve different purposes.
- Who keeps custody of the logbook during construction?
- In practice it stays with the professional in charge on site or with the contract administrator, and it must be available on site to everyone entitled to write in it.
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