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Construction Law/Additional Payment in DB


QUESTION: Dear Florin,

Hope things are working wonderfully fine with you.

I wish to thank you for helping me to take your advice as and when the need arises. You always have been a big help.

My question today reads as follows.

It is about a road project. The Contract is based on the Conditions of Contract for Design –Build and Turnkey, First edition, 1995 prepared by FIDIC.

During the course of execution, change has occurred in the Employer’s requirement of the control points, then, variation was initiated in effect.

The change caused increase in the length of the project road.

Further to the extension of time request the contractor requested additional payment based on schedule of payments, which specifies in percentage the financial components of the contract price.

My question relates to the correct way of determining the additional payment.

The payment schedule says that measurement and payment provisions of the construction shall be lump sum basis and shall be paid upon completion of each of the work items as per percentage proportion provided therein.


For road works, the contractor claimed additional payment based on adjustment factors he worked out on the basis of the increased length against the total length originally envisaged [Factor: increased length/original length].

For pavement works, the contractor considered estimated quantities to determine the difference [as increased length x width minus original length x width] and work out adjustment factors. For the bridges, the contractor took original and revised span lengths.

The adjustment factors were applied to the original value of work items to calculate the additional payment.

How acceptable is the above approach by the Contractor?

What method should one follow to determine the additional payment for the increased length in the absence of SCHEDULE OF RATES in the contract?

As the design is already completed, can the rates be worked out from the amounts given for each item and the quantities known at this stage for the original length?

As usual, I am deeply indebted in advance to your knowledgeable advice.


ANSWER: Hi Alemu,

Good to hear again from you, I am really glad I can help. Thank you for your new question.

In respect of road length, providing the additional length passes through similar ground/ geographical conditions, suggested method should do.

I presume certain margins have been secured when agreeing the prices for the original Contract.

For the bridges, I would rather try to identify bridges in the original Contract, with similar spans, hence, price can be better approximated.

Simply increasing the price with that factor, might not be a good idea, as a bridge of 20 m is not necessary only twice as expensive as a bridge of 10 m.

And since design is ready, yes, that would give you a better ground, rather than just an estimation.

Not sure I managed that well this time, but all in all, based in provided information, it seems to me that any method would do just as good, as it seems a gamble anyway.

I am a bit surprised to hear about that "Design-Build and Turnkey" for a road project.

Good luck!

---------- FOLLOW-UP ----------

QUESTION: Dear Florin,

As usual, I am happy with your prompt and expert reply.

However, I still have one more issue to put forward to you to get your guidance.

In lump sum contracts how or on what basis can the contractor claim extension of time associated costs for the extension of time already granted? What is the best practice that you can advise?

Should the  level of cost for time related obligations be comparable to that in the Tender, which can be proved by reference to the Tender pricing information by the Contractor? If so, should the Contractor be required to produce it.

Once more, I am deeply indebted in advance to your knowledgeable advice.


Hello again, Alemu

Welcome back and thank you for your new question.

I confess I am a bit puzzled, as normally, when you claimed for time, you should have claimed for related costs too.

In my opinion, regardlesd what kind of contract you have, you must demonstrate you have costs related to that EoT and their cuantum.

The first part should be fairly easy, as you probably have records of staff and equipment kept iddle.

The cuantum however, in a lump sum, might be not as straight forward.

But if you referr to records in your accountancy to demonstrate the wages paid to staff and amottisation rates you pay for equipment, that should give you a good starting point.

Would that be a useful idea for your case?

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Questions related to Civil Engineering Contracts, using FIDIC or other Conditions of Contract, concerning Procurement procedures and documents (pre-qualification, tendering and contracting) and Services/ Works Contracts implementation matters including Determinations, Payments, Time Extensions, VOs, Claims/Disputes. Additionally, questions related to dealing with International Financing Institutions. Can also answer questions in Romanian. Can not answer improperly formulated questions.


Over 20 years of experience in the field of design, works supervision, construction, management of aid funds and technical assistance for various types of contracts implementation, including severe conflictual contractual situations leading to Claims and disputes. Claims/ Contract management, Disputes adjudication, Arbitration.

Member of Romanian Professional Association of Roads and Bridges; Listed on President's List of Adjudicators of Romanian Association of Consulting Engineers Former member of the Disputes Resolution Board Foundation (DRBF) of United States – nominee on DRBF President’s Disputes Board Members List and of DRBF Chapter for Eastern Europe Former member of Polish Association of Consulting Engineers (SIDiR) – nominee on SIDiR President’s Disputes Board Members National List Member of “” volunteers pool Member of the "Constructions Disputes Resolution Services” International Panel of Construction ADR Specialists" of United States

- Graduate in 1994 the Construction Institute - Graduate of several FIDIC,Procurement and other courses - Graduate of first Disputes Board Members Mentoring Scheme ( - FIDIC Accredited Adjudicator

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