Points to note regarding fair trade in the construction industry　

Updated: July 2025, 3

① Setting an appropriate estimate period

Presentation of quotation conditions for construction work

If a general contractor fails to provide specific details when submitting an estimate to a subcontractor, or if the general contractor is aware that there is a risk of an event such as ground subsidence that will affect the construction period, but enters into a contract without providing this information, this may be in violation of the Construction Business Act.

<Checkpoint>
Have you provided a quotation detailing specific details such as the work content, start and completion dates, and payment timing and method?

Setting the quotation period

If a prime contractor fails to allow a certain period of time for subcontractors to prepare estimates, this will be a violation of the Construction Business Act.
The required period is stipulated by the Construction Industry Act as follows.

<Checkpoint>
Is there a quotation period based on the planned price for each project?

② Conclude a contract in writing before construction begins!

Construction contracts are signed before construction beginsWrittenContracts that are not in writing, such as oral contracts, and contracts that are issued in writing after construction has begun are violations of the Construction Business Act.

*Reference: Construction Industry Act
(Contents of construction contract)
Article XNUMX　In accordance with the purpose of the preceding article, the parties to a construction contract shall:
When concluding a contract, please note the following matters:Writtenand sign or affix your name and seal.mutually issuedMust.
(Hereafter omitted)

In addition to "written documents,"mutually issued" is also important.
If an order form is issued unilaterally without issuing an order confirmation, this will be considered a violation of the Construction Business Act, as it will not be considered a "mutual delivery."
It is necessary to mutually exchange contracts, order forms, and order confirmations.
　
The contract isBefore construction startsYou also need to be careful about what you need to communicate.

<Checkpoint>
Before construction begins, the general contractor and subcontractor should exchange a written contract detailing the points agreed upon between them, including the necessary matters stipulated by the Construction Business Act.

We also issue written documents to each other in advance for additions and changes to contracts due to additional construction, etc.!

If the contract details are added or changed due to additional construction, etc., a document stating the changes must be sent to each other again.
This is a violation of the Construction Industry Act.

(Article 19, paragraph 2)
The parties to the contract shall confirm that the contents of the contract fall under the matters listed in the preceding paragraph.when to changeIs thatDescribe the changes in writingand sign or affix name and seal.mutually issuedMust.

Modification contracts alsoBefore starting additional construction etc.It is important to note that the information must be exchanged.
　
<Checkpoint>
If you want to change the contract details, you should discuss the work content, construction period, and settlement method for the contract price, and exchange new documents outlining the changes.

③ Set the contract construction period appropriately

It is necessary to secure an appropriate construction period for work style reform in the construction industry.

The annual actual working hours of construction workers are considerably longer than the average for all industries.
The Ministry of Land, Infrastructure, Transport and Tourism is urgently taking steps to address the long working hours of construction industry workers, and the Construction Business Act prohibits contracts with construction periods that are "significantly shorter than the period normally deemed necessary."

Construction Business Act Article 19-5

In order to carry out the construction work ordered by the orderer,Period deemed normally necessarycompared toConstruction period significantly shortenedshall not enter into a contract that provides for.
　

Criteria for determining “appropriate construction period”

The "period normally deemed necessary" must be determined by comprehensively considering the contract details, such as the work content and contract amount, with reference to the "Standards for Construction Periods (Recommendations of the Central Construction Industry Council, July 2020)."

Make sure you can do the work within a reasonable period before signing a contract!

Be careful to ensure an appropriate construction period even when changing contracts.

Care must be taken when setting the construction period, not only in the original contract but also when changing the contract.
Even when a contract is concluded to change the construction period because the work does not proceed as originally contracted or the content of the work changes due to reasons beyond the control of the subcontractor, the above-mentioned Article 19-5 of the Construction Business Act applies, and setting a "significantly short construction period" is also prohibited.

Prevent disputes when changing the construction period at the time of the initial contract.

Disputes are likely to arise when the construction schedule is changed, so in order to prevent these from happening, it is important to clearly stipulate in the initial contract the method of discussion so that you can thoroughly negotiate with the main contractor if the construction schedule is extended or if there is an associated increase in construction costs.

Check items regarding ensuring appropriate construction period

• Have you signed a contract with a construction period that is much shorter than usual?
• If there is a change to the contract terms, such as the construction period, do the main contractor and subcontractor negotiate on an equal footing?
• At the time of the initial contract, did you specify the procedures for negotiating changes to the contract?