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Hea 01 Visual comfort

Number of credits available Minimum standards

Building type dependent

Yes (criterion 1 only)

Aim

To ensure daylighting, artificial lighting and occupant controls are considered at the design stage to ensure best practice visual performance and comfort for building occupants.

Assessment criteria

This issue is split into five parts:

The following is required to demonstrate compliance:

Pre-requisite

  1. All fluorescent and compact fluorescent lamps are fitted with high frequency ballasts.

Daylighting

  1. Relevant building areas meet good practice daylighting criteria as follows:
Area type Credits Daylight factor required Area (m2) to comply Other requirements

Pre-schools, schools, further education-

Occupied spaces

1 2% 80% EITHER (a) OR {(b) and (c)} in the table below

Higher education-

Occupied spaces

1 2% 60%

Higher education-

Occupied spaces

2 2% 80%

Healthcare buildings-

Staff and public areas

2 2% 80% N/A
Healthcare buildings -Occupied patient’s areas (dayrooms, wards) and consulting rooms 3% 80% N/A

Multi-residential buildings-

Kitchen

1 2% 80% N/A

Multi-residential buildings-

Living rooms, dining rooms, studies (inc home office)

1.5% 80% N/A

Multi-residential buildings-

Non residential/communal occupied spaces

2% 80% EITHER (a) OR {(b) and (c)} in the table below
Multi-residential buildings 80% of the working plane in each kitchen, living room, dining room and study (including any room designated as a home office under HEA 20-Home Office – Code for Sustainable Homes) must have a view of the sky.
Retail buildings (sales areas) 1 - 35% Point daylight factors of 2% or more
Retail buildings (other occupied areas) 1 2% 80% EITHER (a) OR {(b) and (c)} in the table below
Court, Industrial, Office, Prison buildings and all other building types
All Occupied spaces, unless indicated below 1 2% 80% EITHER (a) OR {(b) and (c)} in the table below
Cells and custody cells 1.5% 80% None
Internal association/atrium area (prison buildings only) 3% 80% EITHER a uniformity ratio of at least 0.7 OR a minimum point daylight factor of 2.1%
Patient care spaces 3% 80% N/A
Teaching, lecture and seminar spaces 2% 80% EITHER (a) OR {(b) and (c)} in the table below
Retail spaces - 35% Point daylight factors of 2% or more
Ref Criteria
(a)

A uniformity ratio of at least 0.4 or a minimum point daylight factor of at least 0.8% (spaces with glazed roofs, such as atria, must achieve a uniformity ratio of at least 0.7 or a minimum point daylight factor of at least 1.4%)

Due to particular lighting issues in teaching spaces the uniformity ratio can be reduced to 0.3 as defined in BB 87 Environmental Design Standard1BB 87 Guidelines for Environmental Design in Schools, 2003, DFES(this deviation from the criteria can only be considered in circumstances where BB 87 is applicable). A uniformity ratio of at least 0.4 or a minimum point daylight factor of at least 0.4 times the relevant average daylight factor value in Table 5.1 (spaces with glazed roofs, such as atria, must have a minimum point daylight factor of at least 0.7 times the relevant average daylight factor value in Table 5.1) Spaces with glazed roofs, such as atria, must achieve a uniformity ratio of at least 0.7 or a minimum point daylight factor of at least 1.4%.

(b) A view of sky from desk height (0.7m) is achieved
(c)

The room depth criterion d/w +d/HW < 2/(1-RB) is satisfied.

Where:

d = room depth,

w = room width,

HW = window head height from floor level,

RB = average reflectance of surfaces in the rear half of the room,

Note:

Table 6 (see Additional Information) gives maximum room depths in metres for different room widths and window head heights of sidelit rooms

Glare control, view out and internal and external lighting

Building type Glare control and view out requirements – 1 credit (except healthcare, up to 2 credits) Internal and external lighting – 1 credit

Relevant areas in all buildings

Glare control

The potential for disabling glare has been designed out of all relevant building areas either through building layout (e.g. low eaves) and/or building design (e.g. blinds, brise soleil, bioclimatic design that provides shading from high level summer and low level winter sun).

The glare control strategy should be developed in tandem with the lighting strategy to ensure that glare is minimised whilst avoiding potential conflict with the lighting control systems, therefore avoiding higher than expected energy consumption.

AND

View out

All positions within relevant building areas are within 7m of a wall which has a window or permanent opening that provides an adequate view out. The window/opening must be 20% of the surrounding wall area.

Where the room depth is greater than the 7m requirement, compliance is only possible where the percentage of window/opening is the same as or greater than the values in table 1.0 of BS 82062BS 8206-2:2008 Lighting for buildings. Code of Practice for daylighting.

Internal lighting

Illuminance (lux) levels in all internal relevant building areas of the building are specified in accordance with the SLL Code for Lighting 20123SLL Code for Lighting, 2012 and any other relevant industry standard.

For areas where computer screens are regularly used, the lighting design complies with SLL Lighting Guide 74SLL Lighting Guide 7, 2012 sections 3.3, 4.6, 4.7, 4.8 and 4.9. This gives recommendations highlighting:

  1. Limits to the luminance of the luminaires to avoid screen reflections. (Manufacturers’ data for the luminaires should be sought to confirm this).
  2. For up-lighting, the recommendations refer to the luminance of the lit ceiling rather than the luminaire; a design team calculation is usually required to demonstrate this.
  3. Recommendations for direct lighting, ceiling illuminance, and average wall illuminance.

AND

Internal lighting: zoning and occupant controls

The zoning of and occupant controls for internal lighting are in accordance with the criteria below for relevant areas present within the building.

  1. In office areas, zones of no more than four workplaces (see also Compliance note),
  2. Workstations adjacent to windows/atria and other building areas separately zoned and controlled,
  3. Seminar and lecture rooms: zoned for presentation and audience areas,
  4. Library spaces: separate zoning of stacks, reading and counter areas,
  5. Teaching space/demonstration area,
 
  1. Whiteboard/display screen
  2. Auditoria: zoning of seating areas, circulation space and lectern area,
  3. Dining, restaurant, café areas: separate zoning of servery and seating/dining areas,
  4. Retail: separate zoning of display and counter areas
  5. Bar areas: separate zoning of bar and seating areas,
  6. Wards/bedded areas: zoned lighting control for individual bed spaces and control for staff over groups of bed spaces,
  7. Treatment areas, dayrooms, waiting areas: zoning of seating and activity areas and circulation space with controls accessible to staff.

Areas used for teaching, seminar or lecture purposes have lighting controls provided in accordance with SLL Lighting Guide 55SLL LIGHTING GUIDE 5: Lecture, teaching and conference rooms, 1991.

Note, the requirements for zoning of lighting control can be excluded for prison buildings.

The controls specified will depend on the size and use of the space but a typical auditorium or lecture theatre with stepped seating and a formal lectern/demonstration/performance area would typically be expected to have lighting controls as follows:

  1. Full normal lighting (to allow for entry/exit, cleaning etc.),
  2. Demonstration area lighting off and audience area lighting reduced to a low level (for the purpose of line slide projection, but allowing enough light for the audience to take notes),
  3. All lighting off (for the projection of tone slides, colour slides, and for the purposes of visual demonstrations/performances),
  4. Separate localised lectern lighting.

For rooms/spaces not listed above, the assessor can exercise an element of judgement when determining whether the specification is appropriate for the space given its end use and the aim and criteria of this BREEAM issue.

AND

External lighting

Illuminance levels for lighting in all external areas within the construction zone are specified in accordance with BS 5489-1:2013 Lighting of roads and public amenity areas6BS 5489-1:2013Lighting of roads and public amenity areas.

In addition the following is required where applicable;
Education buildings No additional requirement to those outlined above. Manual lighting controls should be easily accessible for the teacher whilst teaching and on entering/leaving the teaching space.
Prison buildings

Cells

An adequate view out from a normal standing or sitting position and the distance between each window and nearest external solid object (i.e. buildings, screens, walls/fences) is 10m.

Where existing features prevent compliance with this requirement in less than 20% of the cells within the building, the credit can still be awarded.

Patient occupied spaces

See Healthcare requirements for these spaces.

Cells

Lit to a maintained illuminance of 200 lux at table-top level. In addition there must be the facility (using, for example, dimming, step switching or separate task and general lighting) for the cell’s occupant to select a lower level of general lighting if required.

Exercise yards

Lit to a maintained illuminance of at least 10 lux. However, if such spaces are, or will be, used as sports facilities they must be lit to a maintained illuminance of 100 lux.

Court buildings No additional requirement to those outlined above.

Separate zoning is also provided for the following areas (as a minimum):

  1. Judge’s/magistrate’s bench,
  2. Dock,
  3. Jury area,
  4. Public seating area.

 

Lighting control of the zones in the above spaces, and the courtroom as a whole, cater for the following settings:

  1. Full lighting (to allow cleaning etc.),
  2. Normal lighting (for court sessions),
  3. Dimmed (for the purpose of showing audio visual evidence, but allowing enough light for note taking).
Multi-residential buildings

Living rooms – (self contained flats), communal lounges, individual bedrooms and bedsits – (sheltered housing)

All positions within relevant areas are to be within 5m of a wall which has a window or permanent opening providing an adequate view out. The window/opening must be 20% of the surrounding wall area.

No additional requirement to those outlined above.
Healthcare buildings with inpatient areas

Patient occupied spaces e.g. wards and day rooms

As criteria above for the relevant building areas PLUS the distance between the wall with the window/opening and nearest external solid object (e.g. buildings, screens, walls/fences) is 10m.

Note: for healthcare buildings with inpatient areas, two credits are available and can be awarded (fully, not in part) for compliance with the glare control and view out criteria outlined above. Where a healthcare building does not have inpatient areas, one credit is available and awarded for compliance with the glare control and view criteria for 'relevant areas in all buildings'.

No additional requirement to those outlined above.

Visual Arts - Healthcare buildings and residential type buildings providing supported living only

One credit

  1. An art coordinator has been appointed for the specific project

OR

  1. An art policy and an art strategy have been prepared for the development at the feasibility/design brief stage i.e. RIBA stage B (or equivalent) and endorsed by the senior management level. The policy and strategy addresses the following:
    1. Enhancing the healthcare environment
    2. Building relationships with the local community
    3. Building relationships with patients and their families
    4. Relieving patient and family anxiety by contributing to treatment or recovery areas, e.g. post-operative areas, paediatric units, etc.
    5. Greening the healthcare environment with inclusion of living plants (where appropriate)
    6. Training generating creative opportunities for staff

Exemplary level criteria

The following outlines the exemplary level criteria to achieve an innovation credit for daylighting:

Area type Credits Daylight factor required Area (m2) to comply Other requirements
All building types The criteria outlined above concerning uniformity ratio, view of sky or room depth criterion are met where they are used to demonstrate compliance.
All building types (excluding Retail – see below)
Functions as identified in the standard criteria (multi storey buildings) 1 3% 80% Where used, a minimum point daylight factor of 1.2% OR 2.1% for spaces with glazed roofs, such as atria
Functions as identified in the standard criteria (single storey buildings) 4% 80% Where used, a minimum point daylight factor of 1.6% OR 2.8% for spaces with glazed roofs, such as atria
Prisons and court cells 2% 80% -
Prison internal association/atrium area 5% 80% A uniformity ratio of at least 0.7 or a minimum point daylight factor of 3.5%.
Retail
Sales areas 1 N/A 50% Point daylight factor 2%
Common areas and offices (multi storey buildings) 3% 80% Where used, a minimum point daylight factor of 1.2% OR 2.1% for spaces with glazed roofs, such as atria
Common areas and offices (single storey buildings) 4% 80% Where used, a minimum point daylight factor of 1.6% OR 2.8% for spaces with glazed roofs, such as atria

Compliance Notes

Ref

Terms

Description

CN1 

Shell only

Pre-requisite - Compliance can be demonstrated via one of the following means in shell only buildings/areas;

  1. Option 1 - Use of a tenancy lease agreement between the developer and tenant/s
  2. Option 2 - A Green Building Guide for tenant fit outs
  3. Option 3 - Developer/Tenant collaboration

Daylighting - No additional notes.

View out - Where it is not possible to confirm which areas of the building will contain workstations/benches or desks, due to the speculative nature of the building, then all areas of the building designed for and/or likely to be occupied by workstations/benches or desks must comply with the relevant criteria (excluding ancillary areas).

Glare control and artificial lighting - Compliance with these aspects of this BREEAM issue can be demonstrated via one of the following means in shell only buildings/areas;

  1. Option 1 – Use of a tenancy lease agreement between the developer and tenant/s (full value of available credits)
  2. Option 2 – A Green Building Guide for tenant fit outs (half the value of the available credits)
  3. Option 3 – Developer/Tenant collaboration (full value of available credits)

Refer to Appendix D – BREEAM New Construction and shell and core/speculative assessments of this Scheme Document for further description of the above options.

Lighting controls - The lighting control system must have the capacity to be zoned, as required, once the final tenant is known and occupancy patterns/layout are agreed.

CN2 

Relevant building areas:

Daylighting See criterion 2

Generally this refers to areas within the building where good daylighting is considered to be of benefit to the building users (typically those areas occupied continuously for 30 minutes or more). Any exclusion will need to be fully justified by the Assessor in their certification report.

This includes the following (where occupied continuously for 30 minutes or more) specifically stated because they are often omitted;

  1. Sports hall exercise spaces
  2. Laboratory areas unless the type of research that will be carried out requires strictly controlled environmental conditions, such as the exclusion of natural light at all times.
  3. Self contained flats
  4. Kitchen and catering areas
  5. General communal areas
  6. Small offices (including those within multi-residential buildings)
  7. Meeting rooms (including those within multi-residential buildings)
  8. Leisure areas
  9. Any area that may involve close up work.

But excludes (where present);

  1. Media, arts production, SEN sensory spaces, x-ray rooms and other areas requiring strictly controlled acoustic or lighting conditions
  2. Clinical areas with controlled environmental conditions, e.g. operating theatres, delivery rooms or pathology. However, BREEAM strongly advise that the benefits from daylighting and view out are seriously considered when designing areas of critical and intensive care in healthcare buildings.
  3. Holding areas and custody cells where security issues conflict with the BREEAM daylighting requirements.
  4. Custody cells in courts, where privacy is a client functional/operational requirement.

CN3 

Relevant building areas:

Glare control and view out

For a view out include areas of the building where;

  1. There are or will be workstations/benches or desks for building users
  2. Close work will be undertaken or where visual aids will be used.
  3. A view out is deemed to be of benefit to the building occupants e.g. in spaces where occupants are likely to spend a significant amount of time.

 

For glare control include areas of the building where lighting and resultant glare could be problematic for users e.g. workstations, projector screens, sports halls.

Excluded areas for each of these might include;

  1. Nurse bases where they are located centrally in a ward/patient area in order to enable patient observation.
  2. Courtrooms and interview rooms where compliance is not possible due to security/privacy criteria.
  3. Prison staff areas that contain workstations that for security or observational purposes must be located centrally within the building.
  4. Any clinical areas where the control of environmental/operational conditions prevents such spaces from providing a view out.
  5. Workstations in nurseries (children’s desks only), conference rooms, lecture theatres, sports halls, acute SEN and also any spaces where the exclusion/limitation of natural light is a functional requirement e.g. labs, media etc.

CN4 

Relevant building areas:

Internal and external lighting

Where no external light fittings are specified (either separate from or mounted on the external building façade/roof), the criteria relating to external lighting do not apply and the credit can be awarded on the basis of compliance with the internal lighting criteria.

The following internal areas are excluded from the lighting zone requirements:

  1. Media and arts production spaces
  2. Sports facilities (exercise spaces only, including hydrotherapy and physiotherapy areas)

CN5 

Percentage of assessed area See criterion 2 Where the compliance requirement specifies that a percentage of floor area must be adequately daylit, it refers to the percentage of the total floor area of all the rooms that must be assessed i.e. the compliant area. If for example a development has 6 rooms that must be assessed, each 150m2 (total area 900m2) and 80% of this floor area must meet the criteria, then 720m2 must comply with the criteria; this is equal to 4.8 rooms. The number of rooms that must comply must always be rounded up; therefore in this example, five rooms must have an average daylight factor of 2% or more (plus meet the other criteria) to achieve the credit.

CN6 

View of sky requirement See criterion 2 To comply with the view of sky criteria ref (b) in at least 80% of the room that complies with the average daylight factor requirement must receive direct light from the sky; i.e. it is permissible for up to 20% of the room not to meet the view of sky requirement and still achieve a compliant room.

CN7 

Adequate view out The view out is of a landscape or buildings (rather than just the sky) at seated eye level (1.2 – 1.3m) within the relevant building areas and should ideally be through an external window. A view into an internal courtyard or atrium will comply provided the distance from the opening to the back wall of the courtyard/atrium is at least 10m (therefore allowing enough distance for the eyes to refocus). The view cannot be an internal view across the room, as this is likely to become obstructed by partitions, filing cabinets etc.

CN8 

Curtains as glare control Curtains do not meet the criteria for the glare control requirement as the control/design needs to allow a degree of flexibility to still allow sunlight in. The use of curtains to control glare would cause occupants to rely on artificial lighting.

CN9 

Relevant industry standard for lighting design

Pre-schools, schools and sixth form colleges: Building Bulletin 90: ‘Lighting Design for Schools’7Building Bulletin 90: ‘Lighting Design for Schools’

Please note that for care homes housing people with dementia the following code can be used instead of the SLL Code for Lighting: Design Lighting for People with Dementia, University of Stirling, Stirling, 20088Pollock R, McNair D, McGuire B and Cunningham C, Design Lighting for People with Dementia, Dementia Services Development Centre, University of Stirling, Stirling, 2008.

Please note that the illuminance levels specified in the SLL Code for Lighting, 2012 are compliant with BS EN 12464-19BS EN 12464-1:2002 Light and lighting. Lighting of work places. Indoor work places, 2003 .

CN10 

Occupancy/workstation layout unknown Where occupancy/workstation layout is not known, lighting control can be zoned on the basis of 40m2 grids i.e. an assumption of 1 person/workspace per 10m2.

CN11 

Small spaces Buildings consisting entirely of small rooms/spaces (less than 40m2) which do not require any subdivision of lighting zones/control will meet the zoning criteria by default .

CN12 

Zones of four workspaces The limit of four workspaces is indicative of the required standard but is not a fixed requirement. Where there is justification for this to be increased to fit with the adopted lighting strategy, this may be accepted provided that the assessor is satisfied that the aim of this criterion is upheld, i.e. that there is suitable zoning/control of lighting to enable a reasonable degree of occupant control over lighting in their personable work area. The lighting consultant should set out how this is to be achieved in such an instance.

CN13 

Borrowed light For areas where borrowed light is used to demonstrate compliance, calculations or results from appropriate lighting design software must be provided to demonstrate that such areas meet the BREEAM criteria (if the light from these sources is required in order for the room to comply). Examples of borrowed light include: light shelves, clerestory glazing, sun pipes or internal translucent/transparent partitions (such as those using frosted glass).

CN14 

Rooms lit from two opposite sides For rooms lit by windows on two opposite sides, the maximum room depth that can be satisfactorily daylit is twice the limiting room depth (d) (measured from window wall to window wall; CIBSE Lighting Guide LG1010CIBSE Lighting Guide LG10 Daylighting and window design, 1999. The reflectance of the imaginary internal wall should be taken as 1.

CN15 

Uniformity with rooflights The room depth criteria cannot be used where the lighting strategy relies on rooflights. In such areas either appropriate software should be used to calculate the uniformity ratio or, in the case of a regular array of rooflights across the whole of the space, Figure 2.36 (p37) within CIBSE Lighting Guide LG10 can be used to determine the uniformity ratio.

CN16 

Point daylight factors and daylight illuminances Computer simulations are the most appropriate tools to allow for point daylight factors to be displayed. 2% daylight factors isolux contours (i.e. lines connecting all the points that have the same point daylight factor value) will need to be mapped on the room plan to check the area where point daylight factors are 2% or higher.

CN17 

Multi-residential developments with CSH assessed dwellings

For buildings with self-contained dwellings also being assessed under the Code for Sustainable Homes (CSH), the following applies:

Where the self-contained dwellings have achieved the credit for CSH issue Hea 1, this contributes toward the daylighting credit within BREEAM. Other residential and non residential areas of the building must comply with the above in order for the relevant visual comfort BREEAM credits to be awarded.

CN18 

Existing site features Where existing site features prevent all self contained dwellings and/or individual bedrooms from achieving the credit requirements. The credit can still be achieved if evidence provided demonstrates that 90% of the self contained dwellings and/or individual bedrooms are able to achieve the compliance requirement.

CN19 

Arts co-ordinator (Visual arts credit)

The assessed project does not need a dedicated arts co-ordinator, the arts co-ordinator may work on several projects, or with several establishments run by the appropriate Trust.

The arts co-ordinator must:

  1. Hold a relevant qualification in an arts or a related subject.
  2. Have at least two years of relevant experience. Such experience should be related to the application of arts in a social context. Examples could be voluntary or paid work within healthcare or educational environments, or with ethnic minority, disabled, elderly or young communities.

CN20 

Nurseries/acute SEN Where child care and/or acute SEN spaces are included within the scope of the assessment, controls should be provided for the teacher/member of staff, i.e. it is not a necessity for the controls to be accessible to the children.

CN21 

Crèche Where nursery spaces are included within the scope of the assessment, controls should be provided for the member of staff, not the nursery school children.

Schedule of Evidence

Ref Design stage
Post-construction stage
Daylighting
All

Design drawings

Daylight calculations

Where relevant for multi-residential buildings:

Evidence in line with the Design Stage evidence requirements of the CSH issue Hea 1 OR

A copy of the Design Stage CSH certificate and report from the CSH online reporting system confirming the number of credits achieved for CSH Issue Hea 1

BREEAM Assessor’s site inspection report and photographic evidence

OR 'as built' drawings, with calculations

Results from on-site measurements (in accordance with methodology detailed in BRE IP 23/9311BRE Information paper 23/93 measuring daylight).

Where relevant for Glare control, view out and internal and external lighting, multi-residential buildings:

Evidence in line with the Post Construction Stage evidence requirements of the CSH issue Hea 1 OR

A copy of the Post Construction Stage CSH certificate and report from the CSH online reporting system confirming the number of credits achieved for CSH Issue Hea 1.

View out and glare requirements
All

Design drawings

Relevant section/clauses of the building specification or contract

Window schedule

BREEAM Assessor’s site inspection report and photographic evidence

And/or 'as built' drawings or a formal letter from the design team

Internal and external lighting
All

Design drawings and/or room data sheets/schedules

Relevant section/clauses of the building specification or contract OR a letter of formal confirmation of compliance from the relevant design team member.

BREEAM Assessor’s site inspection report and photographic evidence

'As-built' drawings

Formal confirmation of compliance from the contractor or design team

Visual arts
All

Correspondence from the design team or Trust (e.g. letter, email, meeting minutes) OR

A copy of the Trust arts policy and strategy.

Documentation demonstrating the work of the appointed arts co-ordinator OR

A copy of the Trust arts policy and strategy

Confirmation of the arts co-ordinators qualifications and experience.

Additional Information

  • Relevant definitions
  • Art
    The Arts Council England defines ‘Arts’ as: “literature and writing, theatre and drama, dance, music, visual arts which include crafts, new media, architecture, design, moving image, and combined arts”.
    Average daylight factor
    The average daylight factor is the average indoor illuminance (from daylight) on the working plane within a room, expressed as a percentage of the simultaneous outdoor illuminance on a horizontal plane under an unobstructed CIE Standard Overcast Sky.
    Clinical areas
    Areas of the building in which medical functions are carried out that require specific restricted environmental conditions such as humidity, daylighting, temperature, etc. (e.g. X-ray, operating department, delivery room, etc).
    Computer simulation
    Software tools that can be used to model more complex room geometries for daylighting.
    Construction zone
    For the purpose of this BREEAM issue the construction zone is defined as the site which is being developed for the BREEAM-assessed building, and the external site areas that fall within the scope of the new works.
    High frequency ballast
    High frequency ballasts increase the frequency of the power coming from the grid (50Hz) to a frequency optimising the performance of fluorescent lamps, typically around 30kHz. There are several advantages to running fluorescent lamps at higher frequencies. At 30kHz, the frequency of re-ignition of a fluorescent lamp is too quick to be detected by the human eye, therefore reducing visible flicker that some fluorescent lamps running on mains frequency fail to do. Additionally, 30kHz being above the audible range of the human ear, the buzzing noise coming out of low quality main frequency ballasts is avoided. Finally, the luminous efficacy of fluorescent lamps increases with frequency; it can be improved by up to 10% when they are running at 30kHz compared to those operating at 50Hz.
    Illuminance
    The amount of light falling on a surface per unit area, measured in lux.
    Occupied space
    A room or space within the assessed building that is likely to be occupied for 30 minutes or more by a building user. Please note there is a specific, unrelated, definition of 'unoccupied' with reference to acoustic testing and measurement and this should not be confused with the definition used here.
    Patient areas
    Areas of the building used mainly by inpatients (e.g. wards, dayrooms, etc)
    Point daylight factor
    A point daylight factor is the ratio between the illuminance (from daylight) at a specific point on the working plane within a room, expressed as a percentage of the illuminance received on an outdoor unobstructed horizontal plane. This is based on an assumed overcast sky, approximated by the ‘CIE (Commission Internationale de l’Eclairage) overcast sky’.
    Public areas
    Areas of the building designed for public use where no medical functions are carried out (e.g. reception, retail unit, waiting areas).
    Separate occupant control
    Light switches/controls for a particular area/zone of the building that can be accessed and operated by the individual(s) occupying that area/zone. Such controls will be located within, or within the vicinity of, the zone/area they control.
    Staff areas
    Areas of the building used mainly by staff (e.g. offices, meeting rooms, staff rooms) and medical areas where patients are admitted but that do not require restricted environmental conditions (e.g. consulting rooms, physiotherapy, etc).
    Uniformity
    The uniformity is the ratio between the minimum illuminance (from daylight) on the working plane within a room (or minimum daylight factor) and the average illuminance (from daylight) on the same working plan (or average daylight factor).
    View of sky/no-sky line
    Areas of the working plane have a view of sky when they receive direct light from the sky, i.e. when the sky can be seen from working plane height. The no-sky line divides those areas of the working plane, which can receive direct skylight, from those that cannot.
    Working plane
    CIBSE LG10 defines the working plane as the horizontal, vertical or inclined plane in which a visual task lies. The working plane is normally taken as 0.7m above the floor for offices and 0.85 m for industry.

    Checklists and Tables

    Table 6 Reflectance for maximum room depths and window head heights.
    The table below gives maximum room depths in metres for different room widths and window head heights of sidelit rooms:

      Reflectance (RB)
      0.4 0.5 0.6
    Room Width (m) 3.0 10.0 3.0 10.0 3.0 10.0
    Window Head Height (m)
    2.5 4.5 6.7 5.4 8.0 6.8 10.0
    3.0 5.0 7.7 6.0 9.2 7.5 11.5
    3.5 5.4 8.6 6.5 10.4 8.1 13.0

    Calculation procedures

    None

    Other information

    The following references provide information relating to this issue;

    1. CIBSE Lighting Guide 10 Daylighting and window design,

    2. BS 8206 Part 22

    3. BRE Site Layout Guide12Site layout planning for daylight and sunlight: a guide to good practice. P.Littlefair, 2005

    Arts and View out in Health

    The implementation of arts in health can have positive effects on patient recovery, staff morale and wellbeing. The benefits include:

    1. Improving clinical and therapeutic outcomes
    2. Helping users to express, contain and transform distress and disturbance, creating a less stressful environment for patients/residents, service users, staff and visitors
    3. Increasing the understanding between clinicians and the people for whom they care
    4. Developing and delivering more patient-focused services, and improving the experience for all.

    For these reasons arts need to find a bigger place within health environments and should be planned from the early stages of development.

    Paintings in Hospitals is a charitable organisation whose objective is to improve the environment of hospitals and other healthcare establishments by providing original works of art on loan. (www.paintingsinhospitals.org.uk)

    Roger S. Ulrich

    Roger S. Ulrich, professor at Texas A & M University’s College of Architecture, has conducted scientific research on the influences of healthcare facilities on patient medical outcomes.

    Professor Ulrich’s paper ‘Effects of Healthcare Environmental Design on Medical Outcomes’ describes the benefits on patient wellbeing and recovery from having adequate views, particularly of natural landscapes. Though it is not a requirement for awarding the BREEAM credit, wards, dayrooms and waiting rooms should ideally have a view out of a soft landscaped area, including planting.

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