Lighting and Visual Comfort Analysis

Management Summary

The use case provides a methodology for evaluating the Visual comfort of an existing building with purpose to inform design strategies towards the renovation of the living space daylight performance. In order to validate the daylight performance of a building for renovation, the process takes will take into account industry standards requirement for daylight and comfort (LEED, BREEAM, WELL). Furthermore, having a real demo case to test, the workflow will cross-reference two kinds of data, the simulated data and the sensor data in order to validate the daylight performances reading and insights.


Use Case Definition

With the growth and accessibility of technology, there has been a shift in how space performs and is being used. Nowadays, our homes are becoming spaces for work and play as well. With these shifts in mind, comfort and performance become relevant factors in the efficiency of spatial design. D.4.4 proposes a standardized method for the implementation of BIM for lighting and visual comfort and the interoperability solutions between the analytical tools and the BIM-SPEED Platform. It also includes the analysis outcomes of the selected real demonstration cases, Vitoria, Spain. The study is performed through climate-based daylight modelling methods using Radiance software. These tools are Climate studio (for Rhino3D) and Insight (for Autodesk Revit) which are the most notable industry-approved software for Lighting and visual comfort simulations with integrated credit validation for LEED, BREEAM, and WELLS. To be validated, compliance or non-compliance indicators of lighting performances metrics are taken into considerations. Because all the demo-case is renovation buildings in various locations and conditions, it is important to utilize a process of assessing lighting and visual comfort that takes into consideration multiple variables such as geospatial location, building true North, physical context, window to wall ratio, interior material reflectance, and weather data. To achieve accurate reading, the research will focus on 2 metrics:

  • Spatial Daylight Autonomy (sDA) takes into consideration location, energy data, building orientation, environmental context, material reflectance.
  • SE/ Glare highlights zones of high solar exposure which supports the wellness added value of understanding the appropriate amount of natural light in alignment with the human circadian rhythms to reduce dependence on artificial lighting and moreover visual discomfort through the glare.


Evidently, this package defines a workflow for the assessment of the spatial visual and lighting comfort in order to reveal opportunities for improvement during the renovation phase. This process aims to reduce time and cost through a computational, human-centric, and industry-standard process towards Visual & Lighting comfort in BIM.

Aim and scope

To assess the demo case Lighting and Visual comfort before and after renovation through industry standard tools to:

  • Assess as-built and renovation daylight performance
  • Inform renovation strategies
  • Design renovation with Industry standard requirements for validation and credit
  • standardize a workflow for seamless design thinking/ integration
  • cross-platform Interoperability

When preparing for the assessment of daylight and visual comfort, there is a consideration towards feasibility in terms of time reduction and integration. In 2021, there are over 20 different computer aided software for simulation of daylight in the market. Each software is categorized based on its interoperability, user interface, learning curve, cross-platform compatibility, IT investment, and workflow, in order to start defining an ecosystem map of all the software fit to the BIMSPEED ambition of reducing cost, time, and providing a cross platform compatibility. There are three software that stands out because of their added value for being able to simulate:

  • Artificial lighting aside from natural light exposure which validate the human circadian rhythm
  • Integrated industry standards validation for LEED, WELL, BREEAM
  • Cross-platform BIM tools compatibility. (Rhino, Revit)

Objectives

To reduce time & cost of a renovation project by adapting a workflow that assesses and validates design strategies for daylight and visual comfort in a renovation project.

Limitations

The measured GIS data accuracy could be a limitation as it is often time not updated regularly or easily accessible.

During the simulation phase, if the IFC model is not accurately packaged (correct family, elements, material passport, true north, layers, etc.), the as-built 3D environment could potentially have missing information that will require being input manual.

In case, the demonstration residents are not compliant to sensor placement in their living space (during the documentation phase), this could lead to insufficient amount of measured real-time data to be compared to the simulation.

References

Data Sheet Standards:

WELL

Requirements

Visual Lighting  Comfort (sDA300,50%)

 Sunlight exposure (ASE1000,250)

WELL Circadian Lighting

average of 215 lux [20 fc]  in the living room.

(sDA300lux,50% achieved for at least 55% of regularly occupied space/year

During the daytime, 200 +  melanopic lux  facing the wall in the center of the room 1.2 m above Ground

average of 50 lux [5 fc] in the bedroom.

(ASE1000lux,250) is achieved for no more than 10% of regularly occupied space/ year

During the nighttime, lights provide no more than 50 melanopic lux  as measured 0.76 m above ground.

average of 100 lux [9 fc]

 

BREEAM

Building/ Area type

Minimum Area to comply

Avg Daylight Illuminance

Minimum Daylight Illuminance

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

80%

At least 100 lux for 3450 hours per year or more

At least 30 lux for 3450 hours per year or more

Non-residential/communal occupied spaces

80%

At least 200 lux for 2650 hours per year or more

At least 60 lux for 2650 hours per year or more

 

LEED

Daylight

 Calculation requirement

Measurement Time

Levels between 150 lux and 5,000 lux for at least 50% of the regularly occupied floor area

Calculate at 9 a.m. and 3 p.m. on a clear-sky day at the equinox.

Measurements during the day sometime between September 1st and October 30th or March 1st and April 30th.

average of 50 lux [5 fc] in the bedroom.

Calculate on a maximum 5 foot (1500 millimeters) square grid.

measure at 30 inches (76 millimeters) above the floor.

average of 100 lux [9 fc]

Exclude blinds or shades from the model. Include permanent interior obstructions. Movable furniture and partitions may be excluded.

 

Abbreviation

DoA: Description of Action

BEM: Building Energy Model

BIM: Building Information Modelling

BS: BIM-SPEED

GIS: Geospatial Information System

IEQ: Indoor Environmental Quality

IPMVP: International Performance Measurement and Verification Protocol

IPR: Intellectual Property Right

KPI: Key Performance Indicator

M&V: Measurement & Verification

POE: Post Occupancy Evaluation

VR/AR: Virtual / Augmented Reality       

UC: Use Case

IESNA: the Illuminating Engineering Society of North America

DF: Daylight Factor

sDA: Spatial Daylight Autonomy

ASE: Annual Sun Exposure

VLT: Visible Light spectrum Transmitted

IFC: International Foundation Class

Project Group

  • , Sharon Verghese (Techniche Universitat Berlin)
  • Filippo Lodi, f.lodi@unstudio.com
  • Sitou Akolly, s.akolly@unstudio.com
  • Andi Balza, a.balza@unstudio.com

Copyright

Handling

The documents reflect the current best practice and do not claim to be complete. They should not to be understood in the sense of a generally valid recommendation or guideline from a legal point of view. The documents are intended to support appointing and appointed parties in the application of the BIM method. The documents must be adapted to the specific project requirements in each case. The examples listed do not claim to be complete. Its information is based on findings from practical experience and is accordingly to be understood as best practice and not universally applicable. Since we are in a phase in which definitions are only emerging, the publisher cannot guarantee the correctness of individual contents.

Logo BIM Speed
  • Document Type : Use Case
  • GUID : CDC47220-FEF4-4F81-92D7-AAE9A584B915
  • Identifier : BIMSpeed_UC7_UNStudio
  • Life Cycle Stage : ISO 22263
  • Revision : V1.1.0.0
  • Project Status : Approved
  • Maturity level : Example
  • Use Case: Draft
  • Processes: Draft
  • ER: Draft
  • Published on: Mar 4, 2022
  • Last change: May 10, 2022
  • Publisher: BIM Speed
  • Author:

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