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  • PublisherCIBSE
  • Product CodeGVA/15
  • Number of pages402
  • Publication DateFeb 2016
  • ISBN

GVA/15 CIBSE Guide A: Environmental Design 2015

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PDF Format







PDF Format






GVA/15 CIBSE Guide A: Environmental Design 2015

NOTE: The pdf of Guide A that can be downloaded or purchased from this page is now a reprinted editon incorporating all corrections identified and made to date. This reprinted edition was published on 17th February 2016.

Further Corrigenda have been issued (see below), and these corrections are incorporated in the downloadable pdf. 

For purchasers of the original edition of the Guide A: 2015, the latest Corrigenda, dated 17 August 2016, can be downloaded here.

CIBSE Guide A: Environmental design is the premier technical/reference source for designers and installers of building services, especially low energy and environmentally sustainable buildings. This is the eighth edition, which comprehensively updates its predecessor. It also contains many significant changes in both format and content.

Chapter 0, Quality in environmental design, is new to the Guide and has been added to consider the quality of the environmental design. It identifies two specific requirements for achieving quality in building design, namely adopting a holistic approach to the design, and a system to assure the quality of the design calculations and decisions, i.e. a quality assurance procedure.

The other chapters in this Guide each deal with an individual aspect of environmental design, namely criteria for design (e.g. comfort criteria, weather data etc.) and methods of calculation such as fabric performance, heating and ventilation system sizing, methods for thermal comfort evaluation, energy demand etc.

The updated contents acknowledge and satisfy current UK legislation, specifically the 2013 Building Regulations Approved Documents L and F, and the recommendations of the Energy Performance of Buildings Directive. Additionally, the authors of each chapter have incorporated the latest published research and recognised best design practice to ensure that environmental design engineers and installation engineers can practise at the forefront of their profession.

Note 1: Chapter 2 of Guide A: 2015 supersedes TM34 Weather Data with Climate Change  Scenarios (2004).

Note 2: The latest Corrigenda (v5.1) is issued 1 June 2016. This incoporates all revisons in one list. Click here to download. This Corrigenda corrects items as detailed below. All those issued up to that date are incorporated in the Guide A: 2015 Reprint published in February 2016. All corrections made to date are incorporated into the downloadable pdf.

Corrigenda 24 Sep 2015
Corrections made to the following text in Guide A:
Prelims – pages v & viCorrections to author/contributor
Page 5-5Text correction in definition
Page 5-62Correction in Fig 5.39
Page 5-85Deletion of 1 reference
Page 6-4Replacement Table 6.3
Page 6-5Correction to caption for Fig 6.2
Page 8-8Note re: section
Page 8-19Correction to caption of Fig 8.9
Corrections made to Appendix 5.A8, supplemental file to Chap 5
Page A8-4Text correction
Page A8-4Correction to Equation A8.35
Page A8-6Renumbering of two Figs
Corrigenda v3 3 Nov 2015 adds:
Page 5-101Changes to Section 5.A6.3
Page 5-102Changes to Section 5.A6.3
Page 5-103Changes to Section 5.A6.3
Corrigenda v4 12 Jan 2016 adds:

Pages 8-7/8-8

The paragraph concerning BREEAM, formerly under section, applies to buildings other than schools and has therefore been moved to become paragraph 2 under section 8.4

Corrigenda v5 29 Jan 2016 adds:

Pages 3-11/12

Table 3.12 revised. Final value for U is unchanged.

Corrigenda v5.1 1 Jun 2016 adds:
Page 0-7/8Changes to text
Page 1-11Changes to Table 1.5
Page 3-19Changes to Example 3.6
Page 3-33Changes to Appendix 3,A6 equations 3.55, 3.59, 3.64 & 3.65
Page 3-42Changes to Tables 3.38 & 3.42
Page 5-28Changes to Equation 5.28
Page 5-33Changes to text of Section
Page 5-77Changes made with new Addendum 
Page 5-97Changes to Table 5.A6.3 & text of Section 5.A6.1(a)
Page 5-98Changes to Table 5.A6.4
Page 7-21Changes to one Reference
Page A8-6Changes to Figure 5.A8.2
Corrigenda v6 17 Aug 2016 adds:
Page 5-84Changes to Equation A2.48

CIBSE Guide A: Environmental Design Launch 

Video highlights and full audio recording are available from the launch event for CIBSE Guide A: Environmental Design 2015 held on 22nd July 2015 at the Grand Connaught Rooms, London featuring: 

Download slides

  • Guide A Steering Group Chair Derrick Braham 

  • Chapter 0 Quality in Environmental Design  - Foroutan Parand 

  • Chapter 1 Environmental Criteria for Design - Fergus Nicol 

  • Chapter 2 External Design Data - Geoff Levermore represented by Derrick Braham

  • Chapter 3 Thermal properties of Building Structures – Brian Anderson represented by Michael Holmes

  • Chapter 4 Ventilation and Infiltration - Martin Liddament 

  • Chapter 5 Thermal Response and Plant Sizing - Chair Michael Holmes / Chair David Williams 

  • Chapter 6 Internal Heat Gains  -  David Arnold 

  • Chapter 7 Moisture transfer and Condensation, Chris Sanders represented by Michael Holmes

  • Chapter 8 Health Issues  -  Marialena Nikolopolou represented by Chair Derrick Braham

Supplementary files

As per the previous edition of Guide A, this edition is supported by a number of data files.  These can now be accessed on-line from an index page here or as indicated below by Chapter.
Note: changes made by the Corrigenda of 24 Sep 2015 to Appendix A8 to Chapter 5 will be incorporated in these files.

Chapter 0, comprising:

  •     Blank PAMDOC and
  •     PAMDOC example

These can be accessed here

Chapter 2, comprising  

  • Annex: Solar radiation, long-wave radiation and daylight
  • World clear sky solar irradiance tables (by latitude)
  • External design data (Worldwide) with index of locations to 139 countries and nummerous locations within each
  • Figure 2.8 Wind roses for the UK
  • Table 2.9 Frequency of dry/wet bulb temperatures (June–September)
  • Table 2.12 Solar irradiation on inclined planes
  • Table 2.13 Solar irradiance on vertical and horizontal surfaces
  • Table 2.14 Sol-air temperatures
  • Table 2.19 Frequency of hourly wind speed by direction
  • Table 2.20 Frequency of hourly wind speed by temperature
  • Table 2.24 Predicted coincident dry and wet bulb temperatures (summer
  • Table 2.25 Predicted coincident dry and wet bulb temperatures (winter)

These can be accessed here

Chapter 5, comprising:

  •     Additional Appendices - ie A7, A8 (amended by Corrigena dated 24 Sep 2015), A9, A10, A11 and A12
  •     Table 5.16 Cooling loads (unshaded) (UK)
  •     Table 5.17 Cooling loads (shaded) (UK)
  •     Table 5.18 Banded weather data
  •     Table 5.X1 Cooling loads (unshaded) (worldwide)
  •     Table 5.X2 Cooling loads (shaded) (worldwide)

These can be accessed here

As an alternative, should it be required the whole set of Supplementary Files can be downloaded from here
Note: this is a large file so this may take some time to download


0 Quality in environmental design
0.1 Introduction
0.2 The design process
0.3 Design calculations quality plan
0.4 Sources of uncertainty
0.5 User issues
0.6 Performance assessment methods (pam)

1 Environmental criteria for design
1.1 Introduction
1.2 Notation and definitions
1.3 Thermal environment
1.4 Modelling thermal comfort
1.5 Environmental criteria
1.6 Additional factors potentially affecting comfort
1.7 Outdoor thermal comfort
1.8 Determination of required outdoor air supply rate
1.9 Visual environment
1.10 Noise
1.11 Vibration
Appendix 1.A1: Determination of predicted mean vote (pmv)
Appendix 1.A2: Measuring operative temperature

2 External design data
2.1 Introduction
2.2 Notation
2.3 UK near-extreme weather data
2.4 UK cold weather data
2.5 UK warm weather data
2.6 Wet and dry bulb temperatures
2.7 Worldwide weather data
2.8 Solar and illuminance data
2.9 Wind data
2.10 Climate change
2.11 Urban heat island effect

3 Thermal properties of building structures
3.1 Introduction
3.2 Notation
3.3 Heat losses from buildings
3.4 Roofs1
3.5 Ground floors and basements
3.6 Windows
3.7 Thermal bypasses
3.8 Linear thermal transmittance
3.9 Non-steady-state thermal characteristics
Appendix 3.A1: Moisture content of masonry materials
Appendix 3.A2: Thermal conductivity and thermal transmittance testing
Appendix 3.A3: Heat transfer at surfaces
Appendix 3.A4: Seasonal heat losses through ground floors
Appendix 3.A5: Application of the combined method to multiple layer structures
Appendix 3.A6: Calculation method for admittance, decrement factor and surface factor
Appendix 3.A7: Properties of materials
Appendix 3.A8: Thermal properties of typical constructions

4 Ventilation and air infiltration
4.1 Introduction and the role of ventilation
4.2 Ventilation and air quality
4.3 Ventilating heat loss
4.4 Ventilation systems
4.5 Natural and mixed mode ventilation
4.6 Methods for estimating air infiltration and natural ventilation
Appendix 4.A1: Basic pressure coefficient data
Appendix 4.A2: Summary of measured air leakage data
Appendix 4.A3: Air infiltration development algorithm (aida)

5 Thermal design, plant sizing and energy conservation
5.1 Introduction
5.2 Notation
5.3 The role of standards
5.4 Relationship to the design process
5.5 Design calculation quality plan
5.6 Thermal response
5.7 Calculation methods for thermal design
5.8 Heating plant sizing
5.9 Cooling plant sizing
5.10 Summertime temperatures in buildings
5.11 Building energy demand
Appendix 5.A1: Overview of calculation methods
Appendix 5.A2: Equations for determination of sensible heating and cooling loads
Appendix 5.A3: calculation of operative and mean radiant temperatures
Appendix 5.A4: Banded weather data
Appendix 5.A5: Glass and glazing systems
Appendix 5.A6: Example calculations
Additional appendices

6 Internal heat gains
6.1 Introduction
6.2 Benchmark values for internal heat gains
6.3 Occupants
6.4 Lighting
6.5 Personal computers and office equipment
6.6 Electric motors
6.7 Cooking appliances
6.8 Hospital and laboratory equipment
6.9 Heat gain from laboratory animals
6.10 Domestic appliances and equipment
Appendix 6.A1: Rate of heat gain from restaurant/cooking equipment

7 Moisture transfer and condensation
7.1 Introduction
7.2 Notation
7.3 Psychrometry of water vapour in air
7.4 Moisture content of materials
7.5 Mechanisms of moisture movement
7.6 Surface condensation and mould growth
7.7 Interstitial condensation
7.8 Inside and outside design conditions
7.9 Condensation calculations
7.10 Control of condensation

8 Health issues
8.1 Introduction
8.2 Thermal discomfort and health implications
8.3 Humidity
8.4 Air quality and ventilation
8.5 Visual environment
8.6 Water quality
8.7 Electromagnetic effects
8.8 Noise and vibration
8.9 Communities and health