[Effective on April 1, 2025] Yokohama City Renewable Energy and Energy Saving Explanation System

The following systems will be established in Yokohama City from April 1, 2025.
Regarding the following two explanatory obligations, the architect who designs the target plan must explain to the architect before the construction of the plan is started.
Renewable Energy Description Obligation
　When designing a new construction or extension of more than 10 m2, the architect will ask the architect about renewable energy use equipment that can be installed in the building.
It is mandatory 　to provide a written explanation.
[Energy saving explanation obligations]
　When designing a new building or extension of a house exceeding 10 m2, in addition to the above, in addition to the above, it also describes the compatibility with insulation performance grade 5 and primary energy consumption performance grade 6.
It is mandatory 　to issue and explain.
　In addition, as an effort rule, efforts will be made to provide a written explanation of the compatibility with heat insulation performance grades 6.7 and airtightness.

※The above flow is an example, and it is possible for architects to respond flexibly based on how they proceed with their own design work. For details, please refer to the following link.

Explanation video about Yokohama-shi renewable energy, energy saving explanation system (outside site)
Yokohama-shi renewable energy, energy saving explanation system commentary text (PDF: 3,733KB)
※This is a slide document of the contents of the video.

For how to use it, see the commentary on the system and use it to provide information to the builder.

If you have any questions about the system, please contact us using the form below.
　Question form (outside site)

We have released the answer to your question. (As of February 14, 2025)
　Answer to your question (PDF: 114KB)

Frequently Asked Questions (PDF: 124KB)
(Contents received in the above inquiry form will be compiled and posted here.)
Ministry of Land, Infrastructure, Transport and Tourism Q & A session (outside site)
(This is a commentary document on the revised Building Energy Conservation Law, etc. Contents related to "Building Renewable Energy Use Promotion Area System" are also posted. )

Various support systems may be available for the introduction of renewable energy equipment and the improvement of energy-saving performance.
For details of each system, please contact the responsible department listed below.

Documents used in this system must be kept for "15 years" based on the Architect Law and City Ordinances.
If you give an explanation, please save a copy of the document used for the explanation.
If the owner does not give an explanation because the owner does not give an explanation, please keep the document that made the statement.
The implementation status of the architect's explanatory duty may be confirmed in interviews with architect offices implemented by prefectures based on the Architect Law.

The renewable energy explanation system is based on the “Building Renewable Energy Use Promotion Area System” stipulated in the Building Energy Conservation Law.
About promotion plans to establish in the law, please confirm page of building renewable energy use promotion area system.
※The energy-saving explanation system is based on ordinances related to the conservation, etc. of the living environment in Yokohama City. For details, please refer to the following website.

※The following explanation is scheduled to take effect on April 1, 2025.
・The entire Yokohama city is a "Building Renewable Energy Use Promotion Area" (Article 60 of the Act).
・When an architect designs for new construction or extensions that exceed the scale specified by the ordinance = 10 m2 in Yokohama City, the architect will write to the building owner about renewable energy use equipment that can be installed on the building pertaining to the design. It is mandatory to issue and explain. (Article 63 of the Act)
　※Excludes when there is a statement from the builder that no explanation is required.

※The following explanation is scheduled to take effect on April 1, 2025.
・An architect who intends to give an explanation must give a legal explanation before the construction of the building starts. (Article 77 of the Enforcement Regulations)

※The following explanation is scheduled to take effect on April 1, 2025.
・When an architect designs a new construction or extension of a house exceeding 10 m2 in Yokohama city, the architect must comply with the energy-saving standards specified in the rules pertaining to the house = insulation performance grade 5 and primary energy consumption performance grade 6. In addition to evaluating the suitability, it is mandatory to issue and explain the results of the evaluation to the owner in writing. (Article 141-14, Paragraph 1 of the Ordinance)
・In addition, as an effort rule, we will evaluate the high-level energy saving standards specified in the rules = heat insulation performance grade 6 or higher and suitability to airtightness, and strive to provide the owner with a written explanation of the results of the evaluation. It is supposed to be. (Article 141-14, Paragraph 2 of the Ordinance)
　※Excludes when the owner expresses his intention not to require an explanation.

※The following explanation is scheduled to take effect on April 1, 2025.
・The architect who intends to give an explanation must give the explanation specified in the ordinance before the construction of the house starts. (Article 88-10 of the Ordinance for Enforcement)