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House Builders’ Standard: Housing Top-Runner Program

House Builders’ Standard (Housing Top-Runner Program) is regulated by the Act on the Improvement of Energy Consumption Performance of Buildings (Building Energy Efficiency Act), which obligates house builders to comply with residential buildings’ energy efficiency standard – 10% higher than the regular standard – up to target year.

 (For further concept of top-runner program, please see the “Top Runner Program” in Policies and Measures Databases of Energy Efficiency.)

1. Background and Current Regulation

In 2009, House Builders’ Standard was introduced as part of the revised Act on the Rational Use of Energy (Energy Conservation Act) targeted to improve energy efficiency for detached houses. House builders who build and sell detached houses for annually at least 150 units were obliged to comply with this standard (See Performance Compliance Path for details) up to 2013. And house builders should annually notify the administrative agency with jurisdiction of their achievements for building energy efficient houses. From 2014 to 2019, this measure will be maintained the same requirement of standard level and reporting.

2. Next Regulation

On the first of July, 2015 "Act on the improvement of the energy consumption performance of buildings" was newly issued. Previously, the energy efficiency improvement of buildings was regulated under the Energy Conservation Act, while, being separating from the Energy Conservation Act, new Act was issued to specifically target at this sector. Under the new Act, energy efficiency level for the House Builders’ Standard is considered to be 15% higher than the regular standard level (in contrast to current 10% higher level) from 2020. Additionally, the Act will mandate the house builders to comply with the insulation standard (See Performance Compliance Path for details).

Under the new Act, mandatory compliance on commercial buildings’ energy efficiency standard (for the buildings whose floor space represent above 2,000 m2) will be introduced from 2017, and the Government is planning to introduce the mandatory compliance on the energy efficiency standard for the commercial buildings (of which floor space represent below 2,000 m2) and residential buildings by 2020.

Applicable Building Type(s)

New residential

Policy Requirement Level

Mandatory

Policy Sequence

Governance

Development Authority: Ministry of Economy, Trade and Industry (METI), Ministry of Land, Infrastructure, Transport and Tourism (MLIT)

Implementation Authority: Ministry of Land, Infrastructure, Transport and Tourism (MLIT)

Verification Authority: Ministry of Land, Infrastructure, Transport and Tourism (MLIT)

Enforcement Authority: Ministry of Land, Infrastructure, Transport and Tourism (MLIT)

Prescriptive Compliance path

Energy Requirements:

Performance Compliance path

House Builders’ Standard

From 2009 to 2019, House Builders’ Standard evaluate primary energy consumption for lighting, air conditioning, ventilation and water heating, while this excludes evaluation for insulation performance. It is important to note that this standard does not evaluate each house they build or sell. House builders are evaluated whether the average of total houses they build or sell – would achieve the standard level.

After 2020, House Builders’ Standard will add Envelope Performance Standard (insulation standard). The details are described below.

 

1. up to 2019

-Energy consumption standard

 Primary energy consumption amount * Design value/Standard value <= 0.90

-Envelope Performance Standard

Exempt from application

 

2. From 2020 (tentative)

-Energy consumption standard

 Primary energy consumption amount * Design value/Standard value <= 0.85

-Envelope Performance Standard

 UA Design value <= Standard value

ηAC Design value <= Standard value

 

* Primary energy consumption is calculated as follows.

Primary energy consumption= heating and cooling + ventilation + lighting + hot water supply – renewable and cogeneration energy

 

**  Urepresent average residential building envelope’s heat transmission coefficient, which is calculated in the following formula.

U= Amount of total heat loss per unit of temperature difference / Total surface area of exterior

  

*** ηAC represent average solar  heat gain coefficient during cooling period, which is calculated in the following formula.

ηAC = 100 x Amount of total solar heat gain per unit of solar radiation intensity / total surface area of exterior 

 

Energy Requirements:

Compliance Softwares:

Calculation program for House Builder’s Standard ver1.2.6

URL: http://ees.ibec.or.jp/app/dat_new.aspx

End-uses considered:

Appliances, Equipment, Lighting interior, Space cooling, Space heating, Ventilation, Water heating

Resources

Notes

Climate zones