Solar control
Glass, shading devices and frit selection
An 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. Crucial to this service is a deep understanding of the potentials and limitations of 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:
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1. Solar Control Glass: The shading effect does not vary during the year; the reduction of solar transmittance reduces daylight transmittance unless selective coatings are used.
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2. 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).
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3. Frit: permanent effect, allows some view to the outside (depending on the frit density) and impacts on the building's appearance.​
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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.
Daylight
Design and performance assessments
Highly glazed façades 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 challenging, especially in office environments.
Although a 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 the visual performance specifications of the given building, can achieve improved views and create a visually sound indoor environment.
Thermal comfort
Assessments of whole body experience and local discomfort
Assessing the perception of the thermal environment is essential to increasing the added value and certifying the design quality. When designing the envelope, key points include setting the correct performance requirements, using proper assessment methods and tools, and accounting for the necessary factors that impact the perception of comfort.
Accounting for parameters such as temperature stratification, direct solar radiation that falls onto the occupants, and local discomfort indices can be essential to provide a sound thermal environment. The need to account for those parameters increases in tall spaces (such as atria), spaces with increased glazed areas (where cold drafts and other local discomfort are likely to occur), and spaces where the uniformity of the thermal environment is essential for the function of the building and the well-being of the occupants (e.g., schools, hospitals, etc.).
When setting performance requirements and striving to meet agreed-upon goals, appropriate thermal comfort models must be selected. 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 façades on thermal comfort is questioned.
Proper use of Dynamic Thermal Modelling (DTM) and Computational Fluid Dynamics (CFD) tools can inform design and ensure a well-perceived, uniform thermal environment while minimizing energy demand.
Advanced façades
Highly glazed and advanced façades assessments
Being the major part or even the whole building envelope, façades impact significantly the performance of the buildings. Highly glazed façades 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 façade options that serve design and ensure enhanced envelope and building performance. Our approach considers the overall performance of the façades 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 façade performance, compliment the architectural vision and keep quality and costs to satisfactory level
Highly-glazed façades: 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 façades: our contribution is to assess performance of complex façades 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 Façades (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
Tailored design tools
Different facade areas in a building experience solar radiation with different intensity and duration. Therefore, using the same glazing build-up for all facade areas might not provide optimum performance benefits. To do that, we need to examine the representative zones from each facade area and assess the solar gains and frequency of shading use (required for solar control).
Controls
Shading use controls
Controls in buildings are required to ensure safe operation and high energy and comfort performance. They can be simple (e.g. timers) or sophisticated, where with the use of sensors they link the HVAC system to motorized facade components, measuring and adjusting specific variables such as air temperatures, lighting levels, ventilation openings, shading systems, etc.
Their main benefit derives from their ability to optimize the building performance by reacting to potential changes at an early stage (e.g. adjusting shading to a momentary increase in beam solar radiation on the facade, permitting natural ventilation to keep indoor temperatures within the comfort levels, etc.). Intelligent, self-learning controls can further understand and predict occupant behaviour. However, providing the occupants with the ability to overlap the controls and influence their indoor environment is most often advised.
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Controls aim to improve energy and comfort by optimizing several performance variables. However, providing the occupants with the ability to override controls and influence their indoor environment is highly advised.
Building physics
Toolbox for a tailored service
Probably one of our strongest assests of our service is out deep understanding of the methods used. A comprehensive toolxoz that consists of diverse methods and a broad range of software programs allow 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.
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Dynamic Thermal Modelling (DTM) tools: DTM tools allow us to assess the envelope performance and suggest appropriate façade 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 façade 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)
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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.
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​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.