- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 19 Jan 2018
BS ISO 17772 - Indoor environmental quality
The main objective of building services engineers and anyone involved in designing a built environment is to create a space conducive to the function of the building. Too often this gets lost in the plethora of other requirements; regulatory, economic and aesthetic.
At BSRIA, we see specifications in which the design parameters are not clearly defined and this frequently leads to gaps between expectation and performance and doubts about whether the completed building meets the client’s requirements. Some specifications indicate winter or summer temperatures, with no mention of tolerances or where the temperatures must be measured.
There are hundreds of useful standards, guides and codes of practice to every aspect of the built environment and of course, BSRIA contributes to this array of publications. But some buildings don’t warrant all the detail from these publications and a basic specification is better than no specification.
A new standard published in January 2018 aims to bring together the key requirements for Indoor Environmental Quality (IEQ) - BS ISO 17772-1:2017 'Energy performance of buildings. Indoor environmental quality. Indoor environmental input parameters for the design and assessment of energy performance of buildings'.
The standard specifies requirements for indoor environmental parameters: temperature, indoor air quality, lighting and acoustics and specifies how to establish these parameters for environmental design. It was drafted to provide a common basis for energy performance calculations but it has wider application as a basic standard for IEQ.
This standard is applicable where the criteria for indoor environment are set for human occupancy and where the production or process does not have a major impact on indoor environment. It includes design criteria for the local thermal comfort factors, draught, radiant temperature asymmetry, vertical air temperature differences and floor surface temperature. It also specifies occupancy schedules to be used in standard energy calculations and how different categories of criteria for the indoor environment can be used.
The standard defines four levels of IEQ:
- IEQi: High level of expectation and also recommended for spaces occupied by very sensitive and fragile persons with special requirements like some disabilities, sick, very young children and elderly persons, to increase accessibility.
- IEQii: Normal level of expectation.
- IEQiii: An acceptable, moderate level of expectation.
- IEQiv: Low level of expectation. This category should only be accepted for a limited part of the year.
The format of the standard is that the user should define the level of performance required for each parameter, to this end it provides forms to be completed by the user in Annexes A to F. However, in Annexes H to L it provides ‘default values’ for the parameters entered on the same forms and these are likely to be widely used.
Temperature is specified as the ‘Operative temperature’ effectively the mean of air temperature and radiant temperature at the building user’s location in most environments, where the air speed is under 0.2 m/s. Adaptive temperature, the user-acceptable temperature modified by the external temperature over the past seven days, is also recognised as relevant for spaces without mechanical cooling.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Do you understand the different types of stone and which ones you should use where?
Why a wellbeing strategy is vital for property managers.
An ECA briefing for members about the commercial implications of leaving the EU.
A crucial moment on any project - and fraught with danger.
The performance gap from a Northern Ireland perspective.
Book review: Buildings of protestant nonconformity.
Design and testing for health and wellbeing - free download from BRE.
Retention in construction contracts.
Campaign for the reform of cash retentions.
The key points for the construction industry and BSRIA's response.
How to make roads safer: the debate continues.