Building Physics
Toolbox for a tailored service
Probably one of our strongest assets of our service is our deep understanding of the methods used. A comprehensive toolbox that consists of diverse methods and a broad range of software programs allows us to use the "best fitted" approach for the challenges we face each time, ensuring project added value.
Our toolbox consists of:
Steady state assessment tools: Steady state tools are used for center pane performance assessments, including the effect of shading (i.e. solar and thermal transmittance, light transmittance, etc). Such tools are WIS 3, and the LBNL suite (Optics and Window). Assessments of thermal bridges are also carried out with steady state methods. We use 2D or 3D heat flow tools (such as Therm) based on international standards to calculate heat losses through constructions.
Dynamic Thermal Modelling (DTM) tools: DTM tools allow us to assess the envelope performance and suggest appropriate facade solutions. They can be used from indicative studies "quantify alternatives" performance at an early design stage), to detailed performance analyses; Thorough understanding of the method is essential to the validity of results.
This information can help architects, building service engineers and facade designers to choose among options that lead to effective sustainable development in terms of the environmental impact and involved cost. Both early stage and detailed calculations can raise awareness regarding potential problems and future-proof the building.
The DTM tools we use are: IDA ICE, Design Builder, Energy Plus and ROOM (Beans Suite)
Computational Fluid Dynamics (CFD) tools:
Our specialized services include CFD assessments that drive design solutions and improve façade and building performance. In order to ensure added project value, we combine CFD with Dynamic Thermal Modelling to properly assess boundary conditions and drive design.
The software we use is the commercial code ANSYS CFX. This software is well-recognised in the industry and has been regularly used in many engineering applications. The capability of this code to model internal building environments is widely accepted.
Daylight assessment tools: Daylight assessment tools can often inform design as to incident solar radiation on the building envelope and to the daylight penetration and distribution within indoor spaces. Such tools are:
(a) Radiance, which is a highly accurate ray-tracing, freeware software tool. The primary advantage of Radiance over simple lighting calculation and rendering tools is that there are few limitations on the geometry or the materials that may be simulated.
(b) DaySim, which is a free Radiance-based daylight analysis software to assess the annual daylight availability and electric lighting use in arbitrary buildings for manual and automated lighting and blind controls.
Typical one-node method
Temperature stratification
Bi-directional flows
Direct Solar Component
Solar Control
Glass, frit and shading devices selection
Essential part of our services is to provide solutions that ensure adequate solar control (minimizing the cooling loads), while allowing for transparency and increased views. Essential to this service is a deep understanding of the potentials and limitations of the solar control mechanisms.
Protecting the building from excessive solar gains is crucial to avoid overheating during the cooling season, while providing adequate thermal and visual comfort levels for the occupants.
The main ways to reduce the transmitted solar radiation through glazing are:
Solar Control Glass: shading effect does not vary during the year; the reduction of solar transmittance results in reduction of daylight transmittance unless selective coatings are used.
Shading devices: variable effect depending on whether shading is angle dependent, movable or angle independent. It is an effective way of shading, but can significantly affect the view to the outside (when applied too often).
Frit: permanent effect, allows some view to the outside (depending on the frit density) and impacts on the building's appearance.
Different shading options can significantly impact on solar performance. Early solar exposure assessments can allow us to inform design by providing effective shading options and low cooling energy use.
Solar Control Glazing
Movable fabrics
Fixed external elements
Facades
Highly glazed and advanced facades assessments
Being the major part or even the whole building envelope, facades impact significantly the performance of the buildings. Highly glazed facades provide a distinctive look, but may often require a specialized knowledge in order to ensure a good solar and thermal performance.
Inform Design's goal is to add value in projects by suggesting facade options that serve design and ensure enhanced envelope and building performance. Our approach considers the overall performance of the facades including impact on building physics and indoor climate.
Our contribution in projects is twofold:
(a) qualify and quantify the alternatives suggested by designers, assess their performance and communicate the benefits of each option
(b) get actively involved in the creative process by suggesting options that can improve the facade performance, compliment the architectural vision and keep quality and costs to satisfactory level
Highly-glazed facades: our role is to touch base with everyday problems
(a) properly assess the performance of glazing and shading systems
(b) properly account for manual or automated controls in the simulation process
(c) suggest solutions that maximize views and daylight while minimizing overheating risk
Advanced facades: our contribution is to assess performance of complex facades and advise on solutions that maximize their benefits. Key point in this process is our deep understanding of the systems and their potentials and the use of elaborated methods that can capture the physics. An example of such systems is Double Skin Facades (DSFs).
The project added value includes selecting proper glass and shading combinations to satisfy four aspects:
(a) Real-life performance: high quality of daylight, connection to the outdoors & privacy
(b) low frequency of shading use
(c) adequate solar performance
(d) sound indoor climate
Single Skin Facades
Double Skin Facades
Daylight
Design and performance assessments
Highly glazed facades can provide a well day-lit environment. However, more daylight does not necessarily mean better daylight. Even though the view to the outside may improve when large glazing areas are provided, visual comfort might be more difficult to obtain, especially in office environments.
Although sound visual environment cannot be easily defined (it depends on personal preferences and the ability to adapt), discomfort or disability factors that affect visual experience can be assessed. Such factors are glare, uneven light distribution, rapid variation of the lighting conditions within the occupied space and the direction of the light (e.g. low sun angles).
Orientation, location and integration of proper shading systems should be considered when designing highly glazed buildings.
Careful design that incorporates advanced daylight techniques at an early stage, considering visual performance specifications of the given building, can achieve improved views and visually sound indoor environment.
Real life daylight
When the blind is down
Daylight Factor
Thermal Comfort
Assessments of whole body experience and local discomfort
Assessing the perception of the thermal environment is essential in order to increase the added value and certify the design quality. While informing the envelope design, key points include setting the right performance requirements, using proper assessment methods and tools and accounting for the necessary factors that impact on the perception of comfort.
Accounting for parameters such as temperature stratification, direct solar radiation that falls onto the occupants, as well as, local discomfort indices can be essential when aiming to provide a sound thermal environment. The need to account for those parameters is increased in tall spaces (such as atria), spaces with increased glazed areas (where cold drafts and other local discomfort is likely to occur) and in spaces where the uniformity of thermal environment is essential for the function of the building and the well-being of the occupants (e.g. schools, hospitals etc.).
The selection of appropriate thermal comfort models is necessary when setting performance requirements and striving towards meeting agreed upon goals. Comfort models such as Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) are most often used for conditioned spaces; adaptive comfort models are more appropriate for transitory spaces and the Universal Thermal Climate Index (UTCI) better describes semi-external spaces. Including the direct solar component is also an important factor especially when the effect of highly glazed facades on thermal comfort is questioned.
The proper use of Dynamic Thermal Modelling (DTM) tools and Computational Fluid Dynamics (CFD) tools can inform design and ensure a well perceived, uniform thermal environment, while minimizing energy demand.
View angles & MRTs
Operative Temperatures
Corrected Operative Temperatures