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Construction Law/Interface Program Issues on Projects


Dear John,
We are one of the interfacing parties( main contractor for civil works) on a railway project under FIDIC 1999 designed by Employer contract.
As a main contractor we have submitted our program of works and included time slots of other interfacing parties work to do their work matching our schedule for completion. The question is whether  other parties are obliged to follow our program because they have their own program and delivery dates as per their contract.Some of other parties works fall after our contract completion date and the works have to be integrated to complete the project.
Kindly advice
Which program will prevail?
Are the other parties legally bound to follow our program?
Can we ask interface party to sign Rules and Regulations which we developed to be imposed on them while they are working in our area to complete their part of the job?

Dear Abdul,

Thank you for this question.

If those other contractors are engaged by the Employer and not by you as Main Contractor, it is for the Engineer to manage the programme durations and the trade inter-relationship. Only your programme applies to your contract. Unless the contract states otherwise, you are not obliged to follow the programme of others and they are not obliged to follow your programme.

From your narrative I note that you have included (reasonable) time allowances within your schedule. This is a prudent approach where you were uncertain of the scope and timing of work by others and the Employer/Engineer did not provide adequate information.

If the other contractor's programmes/schedules interfere with your rate of progress you will be entitled to claim for an extension of time and/or disruption costs to the extent you can demonstrate.

If the work o0f others falls after the Employer taking-over your works, it is for the Employer to manage the risk. If others work whilst you are still on site you will have to look at you8r contract to determine how the risk was allocated and the extent of any obligations you, or they have. It may be possible to set "rules" but whether such are binding is doubtful.

I hope that this assists you.

Kind regards,
John Dowse

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John Dowse


Legal; contract interpretation; quantum; delay analysis. Practitioner in arbitration, adjudication and mediation.


Thirty-three (33) years experience in building and construction, at all levels both within contracting and consulting organisations. Practising arbitrator, adjudicator, and mediator. Faculty approved trainer for the Chartered Institute of Arbitrators. Lecturer on construction contract forms and dispute resolution practices.

Chartered Institution of Civil Engineering Surveyors Chartered Institute of Arbitrators Institute of Directors Society of Construction Arbitrators

Various UK and International construction and legal publications.

LLB (Hons), Pg Dip (Legal Practice), MCInstCES MCIArb MIOD Barrister

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