Multi-Paned Glazing


Target Scope

Multi-paned glazing, except the following:

1) ones using stained glass,

2) ones for which the total sum of the thicknesses of the glazing that constitute the multi-paned glazing exceeds 1 cm, or

3) heat reflecting glazing specified in JIS R 3221 (2002).


Heat Loss Prevention Performance

Heat loss prevention performance shall be heat transmission coefficient (W/(m2・K)) found by the method stipulated in JIS R 3107 (1998)*1.

*1: A separate method is established for multi-paned glazing that uses vacuum glazing.


Categories & Target Standard Values

In the target fiscal year and each subsequent fiscal year, the weighted average value obtained by weighting heat loss prevention performance with dimension shipped shall not be above the target standard value which is a weighted average value obtained by weighting standard heat loss prevention performance*2 with dimension shipped.

*2: For multi-paned glazing whose thickness of layer is from 2mm up to 16mm, values obtained from the standard heat loss prevention performance calculation formula.

Thickness of layerStandard heat loss prevention performance or the calculation formula
Less than 2 mm3.85
2 mm or more and 16 mm or lessU=-1.00In(X)+4.55
Over 16 mm1.77
  1. “Thickness of layer” is the distance of the space that occurs between the paned glazing placed side by side. In this case, the value is the total sum of the thickness of the layers when multiple layers exist in one multi-paned glazing.
  2. U and X indicate the following numeric values:
    U: Standard heat loss prevention performance (unit: W/(m2・K))
    X: Thickness of layer (unit: mm)
  3. In indicates the natural logarithm.


Target Fiscal Year

FY2022 and each subsequent fiscal year


Performance Improvement

Heat loss prevention performance is expected to be improved by 7.33% compared with the FY2012 level in the target fiscal year (FY2022).

* The improvement rate is calculated based on the assumption that the shipment share by layer thickness stays at the same level in FY2012.


Display Items

●Product name or type

●Heat loss prevention performance

●Name of manufacturer, etc.


Display Location

Display items shall be presented at locations where they can be readily noticed in catalogs showing performance indications or documents provided by the manufacturer for product selection.


Requirement for Recommendations and Orders

Manufacturers, producers or importers whose annual manufacturing volume or importing volume (limited to shipment to the domestic market) is 110,000 m2 or more may be subject to recommendations and orders.