GB/T 20311-2021Building components and building elements - Thermal resistance and thermal transmittance - Calculation methods (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1.Structure and Drafting Rules of Standardization Documents"

Drafting.

This document replaces GB/T 20311-2006 "Calculation Method for Thermal Resistance and Heat Transfer Coefficient of Building Components and Building Units", and

Compared with GB/T 20311-2006, in addition to structural adjustments and editorial changes, the main technical changes are as follows.

--- Added the term "EPB Standard" and its definition (see 3.6);

---Modified the table of symbols and units (see Chapter 4, 3.2 of the.2006 edition);

---The calculation method has increased the detailed algorithm (see Chapter 5, 6.5.1);

---Add input values, output results, constants and other tables (see Chapter 6);

---Modified the principle of the simplified algorithm (see Chapter 6.4, Chapter 4 of the.2006 edition);

---Adjusted the order of the simplified algorithm chapters (see Chapter 6, Chapter 5, Chapter 6, and Chapter 7 of the.2006 edition);

---Added a normative appendix "input and method selection tabulation" (see Appendix A);

---Added an informative appendix "input and method selection reference" (see appendix B);

---Modified part of the calculation content of surface thermal resistance and adjusted it to a normative appendix (see Appendix C, Appendix A of the.2006 edition);

---Modified the calculation content of the thermal resistance part of the air space and adjusted it to the normative appendix (see Appendix D, Appendix B of the.2006 edition,

Appendix F);

---Modified the calculation of the thermal resistance of components with wedge-shaped layers and adjusted it to a normative appendix (see Appendix E, Appendix C of the.2006 edition);

--- Modified part of the content of the heat transfer coefficient correction, and adjusted to a normative appendix (see Appendix F, Appendix D of the.2006 edition).

This document uses the translation method equivalent to ISO 6946.2017 ``Calculation of thermal resistance and heat transfer coefficient of building components and building units

method".

This document was proposed by the China Building Materials Federation.

This document is under the jurisdiction of the National Thermal Insulation Material Standardization Technical Committee (SAC/TC191).

Drafting organizations of this document. Nanjing Fiberglass Research and Design Institute Co., Ltd., Anhui Hongchang New Materials Co., Ltd., Henan Chengjian Inspection

Inspection Technology Co., Ltd., Suzhou Huaxia Design and Construction Co., Ltd., Zhejiang Yicheng Inspection Co., Ltd., China Construction Xinjiang Construction Engineering (Group)

Limited company, the national glass fiber product quality supervision and inspection center.

Introduction

The series of international standards for building energy efficiency assessment is also known as the "EPB series of standards." EPB series standards follow the same rules to ensure

Consistency, continuity and openness among the standards in the series.

ISO 6946.2017 is one of the EPB series of international standards. The standardization goal is to achieve building energy efficiency through building energy efficiency assessment

Rating, the position in the series of standards is shown in Table 1.The main target audiences of the standards are architects, engineers and regulatory agencies.

Table 1 The position of ISO 6946.2017 (M2-5) in the module structure of the EPB standard group

General Building System Technology

Sub-module description description description heating, cooling, ventilation, humidification, dehumidification, hot water lighting

Building from

Dynamic and

control

Photovoltaic

Wind energy

Subject M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11

1 General General General Purpose

Common terms and

Definition; symbol,

Unit and subscript

Building energy

need

Demand a

3 Application

No system

Indoor conditions

Maximum load

And power

4 Energy expression method

Energy expression

Way

Energy expression

Way

Building category and

boundary

Heat transfer coefficient

ISO

Launch and

control

6 Convective heat transfer under operating conditions

Distribution and

control

Energy services and

Energy carrier

polymerization

Heat Conduction

Storage and

control

8 Increased solar heat in building zones

Generate and

control

9 Energy efficiency calculation heat mass

Load scheduling and

Operating condition

10 Energy efficiency test Energy efficiency test Energy efficiency test

11 Inspection inspection inspection

Indoor comfort

Express

BMS

13 External environmental conditions

14 Economic calculation

a The shaded module is not selectable.

For more information, please refer to the technical report (ISO /T R52019-2).

In addition to ISO 6946.2017, ISO /TC163/SC2 is responsible for the standards belonging to the EPB series.

---The calculation procedure for the overall energy consumption and energy efficiency of the building;

---The calculation procedure of the indoor temperature of the building (e.g., assuming there is no internal heating or cooling);

---Part of EPB energy balance and structural characteristics index requirements;

---Energy efficiency of some special buildings and special building components or units (such as floors, opaque packaging units, windows, facades, etc.),

Calculation methods for heat, damp heat, solar energy, and visual performance.

This document is equivalent to ISO 6946.2017, which provides the heat transfer coefficient and thermal resistance of building components and building units such as roofs and walls.

Calculation method.

---Provide a unified method for the comparison between different structures;

--- Provide a standardized basis for determining whether building components and building units comply with laws and regulations;

---Provide data support for calculating the energy required for heating or cooling buildings.

Thermal resistance and heat transfer coefficient of building components and building units

Calculation method

1 Scope

This document gives the calculation method of thermal resistance and heat transfer coefficient of building components and building units, but does not include doors, windows, and other glass

Components, curtain walls, components that transfer heat to the ground, and components designed for ventilation.

This calculation method is based on the appropriate design thermal conductivity or design thermal resistance of materials and products related to the application.

This document applies to building components and units composed of a thermally homogeneous layer (which may include an air layer).

Appendix F of this document gives the approximate calculation method for the non-thermal homogeneous layer of metal fasteners, but it does not apply to metal thermal bridges.

The insulation layer.

Note. According to the modular setting specified in ISO 52000-1, Table 1 in the introduction gives the relative position of this document in the EPB series of standards.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations

Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

This document.

ISO 7345 Insulation material physical quantity and definition (Thermalperformanceofbuildingsandbuildingcompo-

nents-Physicalquantitiesanddefinitions)

ISO 10211 Detailed algorithm for thermal bridge heat flow and surface temperature in building structures (Thermalbridgesinbuildingcon-

struction-Heatflowsandsurfacetemperatures-Detailedcalculation)

ISO 10456 Construction materials and products heat and humidity performance claim value, design value selection procedure and design value tabulation

(Buildingmaterialsandproducts-Hygrothermalproperties-Tabulateddesignvaluesandprocedures

fordeterminingdeclaredanddesignvalues)

ISO 13789 The calculation method of heat transfer coefficient and ventilation coefficient of building insulation performance (Thermalperformanceof

buildings-Transmissionandventilationheattransfercoefficients-Calculationmethod)

ISO 52000-1.2017 EPB Evaluation System for Building Energy Efficiency Part 1.General Framework and Procedures (Energyperformanceof

buildings-OverarchingEPBassessment-Part 1.Generalframeworkandprocedures)

Note 1.Except for ISO 52000-1, the default EPB reference file is determined by the EPB module code and is given in Appendix A (Table A.1) and Appendix B (Table B.1).

Example. EPB module code. M5-5 or M5-5, 1 (if M5-5 is subdivided), or M5-5/1 (if specific chapters in document M5-5 are cited).

Note 2.This document does not quote other EPB document clauses. The above statements and notes are to maintain the consistency of the EPB series of documents.

3 Terms and definitions

The following terms and definitions defined by ISO 7345 and ISO 52000-1 apply to this document.

3.1

Buildingelement

The main part of the building.

Example. wall, floor or roof.