Author name: Petros Karatzas

Natural Anodized Cladding: Dirk Verwimp

Blog, Europe /

Natural Anodized Aluminium Cladding Panels have been around the architectural market for several decades now. The use of natural anodizing though in cladding panels have not been as widespread as natural anodizing in extrusion profiles. Though, it is indeed an excellent option to consider with. We discuss with Dirk Verwimp, an expert in this field and currently Business Unit Manager for Almeco Group in Italy. Skyline Facades: Dirk, what are the advantages of natural anodized cladding panels? Dirk: There are actually several. To start with, the anodic layer is inherent to the aluminium substrate, so it will never peel, chip or chalk. Anodising for facade cladding is a durable and sustainable solution with an unlimited design lifetime. In case of replacing the panel, the material is very easy to recycle at a fraction of the energy to produce new aluminium. The material is UV resistant and the metallic lusture and gloss will be maintained over time. Pre-anodised facade cladding is easy to maintain and is graffiti proof. And finally, it is a 100% pure aluminium product with an attractive aesthetic appearance. Umeus Student Home, Copenhagen / Denmark Skyline: There are pre-anodized cladding panels and post-anodized cladding panels. What are the actual differences? Dirk: Selecting pre-anodising will enhance your cost efficiency as the material can be post transformed into any type of cladding. Further, due to the constant and automatic processing on coils, the material will have an excellent uniformity. After the process , the coils can be levelled and cut into stress free sheets, which avoids tension in the cassettes. Post anodising is mostly selected in case of extruded profiles or for very complex structures. As the process is manual, it is very work intensive which is reflected in the cost. As one load contains no more than 20-30 m2, there is a risk of colour and gloss variation on your facade. With post anodising you can achieve higher anodic layers, as prescribed in the British Standards, but this is in fact not always an insurance for better quality. These high anodic layers are often forced which results in a soft top layer that can be reduced over time. Ideally pre anodised material is used for large facade surfaces where uniformity is essential, with the combination of batch anodised extruded profiles for the trims or finishing parts. Learown Fuda Square, Shenzhen, China Skyline: What are the finishes that can be achieved with natural anodizing? As architects, or façade consultants, do we have a wide range to choose from? Dirk: Generally anodising can be provided on different type of textures. Standard and well known in the market is the mill finish surface, which is a smooth and satin surface. But more and more different textures are requested by architects, where brushed, sand blasted and BRITE finishes or textures can be offered. The pre-treatment on these textures are different and usually the chemical etching part in the process is skipped in order to maintain as much as gloss or brushed definition as possible. Besides the different textures, modern natural anodizing offers also a wide range of colours: natural, gold, bronze, copper and zinc. Each of these colours will look different on different textures. This allows the architect to maximise its creativity by combining the preferred textures with the preferred colour tone. Bloom College, Wavrin / France Skyline: Can you explain us briefly the production process for natural anodized cladding? Dirk: The standard alloy for mill finish anodised aluminium is 5005 H14. The optimal anodic layer is 15 microns for exterior use, depending on the specification. We can  offer also 20 and 25 microns on coil depending on the location of the project. The process starts with a 3 step pre-treatment: degreasing for oil removal, etching for defining the right gloss and neutralisation to clean the smut and block the pH entering the acidic anodising tank. After the anodising step, the material can be coloured, where pigments or metal salt is deposited into the porous structure of the anodic layer. Finally, the material is sealed in a hot water tank, closing the porous structure and fixing the colour. It is important to opt for a QUALANOD certified supplier which ensures the quality and processing according European norms and standards. E-Sport Arena, Hangzhou / China Skyline: Is anodized cracking, when bended, an issue? Dirk: If you produce cassettes or other types of panels from pre-anodised aluminium, you will always have superficial hairlines perpendicular to the rolling mill directions. This superficial hairlines, also called crazing, is a natural effect and only visible under certain angels and light. This phenomena is purely aesthetical and will not affect the quality nor the warranty. We always recommend to reduce the bending radius to a minimum (in accordance with the limits of the metal substrate) in order to minimise the area of the crazing. Chang’An Cloud, China Skyline: What is the actual lifetime of a natural anodized cladding panel and what are the factors that affect it? Dirk: Natural anodized suppliers provide different warranties, for us  25 years of warranty is a standard, but in fact the design life is unlimited. The material is 100% pure aluminium and has a very strong resistance towards weathering. Factors that can influence the lifetime is direct contact with cement, acidic or alkaline substances which can attack the anodic layer. This must be avoided.

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Ventilation and A/C System Design Adaptation: Frederik Winther

Blog, Europe /

Is your building future weatherproof? Future weather will bring increasingly higher temperatures and humidity. This poses a challenge for the indoor climate in our buildings, as cooling and ventilation system design is based on historical weather data that is more than 10 years old. If we don’t change our design practices, our buildings will overheat. In this article, Frederik Winther – Senior Specialist Manager in Ramboll Denmark – along with his colleague Dragos Bogatu, explore the challenges that the future climate poses to our buildings’ ventilation and air conditioning systems and outline the change in approach to design and solutions needed to mitigate them. Frederik works for almost 12 years at Rambøll Danmark’s main office in Copenhagen. Started as a consulting engineer in the Department of Indoor Climate and HVAC. After 3 years at Rambøll he started his PhD project on Intelligent Glazed Facades. Did research on the potential of facades in future low energy buildings as well as experimental investigations on the performance of advanced facades. He has developed numerical calculation methodologies for advanced facade technologies such as PCM in glazing, dynamic g-/U-value technologies. Having been awarded his PhD degree he was employed at Rambøll working in greater depth with facade design and numerical analysis of thermal building simulations and CFD calculations. His work consists of consultancy work for many projects. We talk with Frederik about Ventilation and Air Condition System Design Adaptation to Climate Change and the subsequent challenges, approach and solutions. Original article was posted by Frederik in LinkedIn https://www.linkedin.com/feed/update/urn:li:activity:7208776945730265089/ Ventilation and air conditioning system design adaptation to climate change: Challenges, approach, and solutions Future weather will bring increasingly higher temperatures and humidity. This poses a challenge for the indoor climate in our homes, but especially in large buildings, as cooling and ventilation system design is based on historical weather data that is more than 10 years old. If we don’t change our design practices, our buildings will overheat. A change in mindset but also policy recommendations are required.   Expected changes in the Danish climate. Denmark’s future climate won’t only include more frequent storms, heatwaves, and heavy rainfall. It will also become warmer, with increased humidity. This is evident from DMI’s new Climate Atlas for Denmark’s weather [1] based on projections from the UN’s climate panel and Aalborg University, Department of the Built Environment, covering the period from 2030 to 2100. Annual temperatures are expected to rise by over 3°C. Looking at the number of heating degree days (HDD) – a measure of coldness – they will decrease by almost 30%, from 3319 HDD in the period 2001-2010 to 2271 HDD in 2090. Humidity will also increase significantly, as shown in Figure 1, based on data projections from IPCC [2], [3]. The number of hours per year with water content higher than the current 12.5 g/kg (which we currently design our ventilation systems for) will rise from 67 hours (~9 workdays) to up to ~250 hours (~34 workdays) by 2040. Figure 1. Humidity levels as a function of projected weather data in Copenhagen, Denmark compared to the Danish design reference year [2], [3], [4]. At the same time, rising temperatures and humidity will impact our perception of heat. Higher humidity makes it harder for the skin to dissipate heat. When combined with high temperatures, heat transfers from the air to the skin, making us feel significantly warmer. Both existing and future buildings must adapt to significantly different conditions than what we are used to. Failing to account for the warmer and more humid weather, will have detrimental consequences for the indoor climate and the cooling and ventilation systems we rely on. Homeowners are already grappling with warmer and more humid weather. If anyone doubts that these changes affect the indoor climate of our buildings, they need only ask homeowners. In the survey ‘Danskerne i det byggede miljø’ [5], conducted by Realdania and Videnscentret Bolius, over 12% of residents in homes built after 2000 report that their homes are too hot. Especially during the summer, overheating is a real issue. The challenge lies in larger window areas present in new buildings and changes in architectural preferences, which do not provide the same opportunities for natural ventilation and solar shading as older homes do. Mechanical ventilation and cooling are not common practice in Danish homes. Therefore, the indoor climate challenges, in newer residential construction, cannot be directly compared to large-scale buildings. However, it does emphasize the consequences of a changing climate on our indoor environment and the need for change in design approaches. Historical weather data does not consider climate change. Despite projections showing our climatic future, we still use 10-year-old historical weather data when designing cooling and ventilation systems. While we gradually adjust the standards we design for, the changes are insufficient given the climate shifts we anticipate. We risk having buildings where cooling and ventilation systems cannot maintain satisfactory air quality and humidity levels for their intended use. The consequence is overheating. This poses problems for building occupants, affecting well-being, health, and cognition. It’s also a challenge for building operators, as operating undersized systems becomes more expensive. Lastly, it’s an environmental concern because energy-intensive systems consume more than they should. Consider an average office building as an example. Calculations suggest that without other adjustments, we should increase the size of cooling surfaces in ventilation systems by up to 25% and enhance cooling system efficiency by up to 50% by 2040 compared to current Danish standards. Even by 2030, within the lifespan of new installations, the increase is significant. In some cases, simply increasing performance won’t suffice. In extreme cases, existing systems may need improvement or complete replacement with more powerful ones to handle future weather conditions. On the other hand, undersized cooling and ventilation systems are costly to operate due to high energy expenses and maintenance costs. The solution is a climate resilient design. Climate resilience refers to the ability of the designed systems and assets to withstand shocks and stresses as well as the

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Facade Engineer Greece

Facade Engineering in Greece: Anna Ioannidou Kati

Blog, Europe /

Anna Ioannidou Kati is a Senior Facade Engineer in one of the most famous facade engineering offices globally, Eckersley O’ Callaghan (EOC). She’s holding a Civil Engineering degree from Technical University of Athens and an M.Sc. in Building Engineering from Delft University in Netherlands. Based in London for the last 5 years, Anna managed the Facade Engineering services for Piraeus Tower, probably the first project in Greece where a facade consultant was appointed. We discuss with Anna her experience, as well as the reasons why Facade Engineering is a common practice in many countries globally but not in Greece, at least yet. Anna, what is the real value that facade engineering brings in the projects? Facade engineering can bring significant value to projects. As a discipline it aims to enhance both architectural aesthetics and performance of building envelopes. It looks at how the facade can influence energy efficiency, daylight, indoor thermal and visual comfort of buildings. As facade engineers we also investigate and ensure the buildability and structural integrity of the architectural proposals from early stages.  Overall, facade engineering plays a crucial role in achieving sustainable, visually appealing, and high-performing building envelopes. Why do you believe that facade engineering is not popular in Greece yet? As far as I am concerned, Piraeus Tower was the first project that this function actually applied to.  Facade engineering is a relatively new discipline not only in Greece, but even across the world. Architects and engineers were always collaborating to explore new materials and technologies for building envelopes, but the term and specialization ‘facade engineering’ probably emerged in the last 50 years or so. With the advent of modern construction methods and the increasing complexity of building designs, facade engineering became more and more popular. Also, the increasingly strict regulations related with sustainability that slowly came into effect in the last 10-15 years increased the complexity of facade designs and led to a demand for specialist consultants that could advise on facade technologies and performance. In Greece, traditionally, there was an intentional simplicity in architectural designs of building envelopes. This tendency likely stemmed from our country’s high seismic activity, leading to simple buildings in plan, and simple architectural elements and materials to the building exterior. Of course, the recent recession contributed to the construction industry being dormant for a few years. During this period, very few large and complex buildings were designed and constructed, and thus the circumstances did not allow for this discipline to emerge and grow like the rest of Europe and abroad. Would you think that this discipline will have bigger demand in Greece in the coming years? Greece seems to be entering a new era as it is starting to experience a significant growth in the construction sector. Private and government initiatives are slowly driving investments in new construction developments. We are currently seeing various notable new projects under construction, such as large mix-use buildings, high-rise towers, and refurbishments. We also see more and more ambitious and complex designs from Architects who are not afraid to explore new materials and technologies. This is where facade engineering can play a crucial role guiding Architects and Clients in achieving buildable, sustainable, and high-performing envelopes. Therefore, I do believe this discipline is going to grow in Greece in the next few years. What was the biggest challenge that you faced in Piraeus Tower? The biggest challenge we faced was probably the construction method of the facade. The industry across the world has embraced the design of unitised curtain walling for tall and repetitive buildings, such as Piraeus Tower, due to the benefits of the off-site manufacturing. However, due to the lack of tall buildings in Greece, this system had never been applied in any project and there was an understandable hesitance on the ability of the local market to deliver this project technically and within time and budget. During this process we had multiple discussions with Greek system suppliers and installers. We understood that the industry had the required ‘know-how’, they were only waiting for the right opportunity to put this knowledge into effect. I am very glad that Piraeus Tower was built with a unitised system, as this makes it the first building in Greece where this technology was applied and stigmatizes a new era for constructing tall buildings in Greece. In what stage exactly did you get involved in this project?  Ilias Papageorgiou from PILA reached out to EOC during the competition stage to provide technical support on their facade design proposal for Piraeus Tower. During the competition, we explored options for the construction method of the facade and investigated the optimization of the external shading fins. It is very fulfilling being involved in projects from such early stages, as this is the time when important decisions are made. We delivered a technically feasible design proposal and provided confidence to the Client that the design was buildable and efficient. Collaborating with architects for competitions is something we do very often, and we see more and more architects requesting our input due to the increased value we can bring in projects. Tell us a few things about the dynamics in the project team. By project team, I mean the Architect, the Client, the General Contractor, the Facade Contractor. Dynamics in project teams can vary depending on the type of project and the procurement process. The Architect is responsible for designing the overall appearance of the building and often acts as lead designer. They need to work closely with Clients to understand their vision, programme and budget constraints. Clients on the other hand, need to be actively involved in the decision-making process and constantly provide feedback on the design team’s proposals. The General Contractor is responsible for managing the construction phase of the project, while the Facade Contractor is appointed to design and build the building envelope. The sooner the General Contractor is involved in the project, the more influence they can have on the design solutions. As facade engineers, we often

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Why do projects delay

Why Projects Delay: with Matt Verderamo

America, Blog /

Matt Verderamo is Vice President, Preconstruction & Sales at Alliance Exterior Construction in Baltimore, Maryland. Alliance is a specialty subcontractor focusing on glazing, metal panels, and roofing. Matt is also a proponent of mental health and career growth in the construction industry. Follow him on LinkedIn and Twitter, and check out his website here (mattverderamo.me) Our discussion with Matt is Why do Projects Delay. WHY DO PROJECTS DELAY In his national best-selling book, “Atomic Habits”, James Clear describes the importance of upstream habits. Let’s say you want to eat healthy. Clear would argue that one of the best ways to ensure you do that is to create an “upstream habit” that influences the behavior. For him, it is all about a morning workout. When he works out in the morning, he finds that he is more likely to eat healthy! He doesn’t need to try to eat healthy, he just needs to make sure he works out, and then he naturally wants to eat healthy! This morning workout also influences his alcohol intake, stress levels, and overall health. This is the benefit of an “upstream habit”: it is a simple habit that influences a lot of other good habits downstream. When I think about Construction projects and why they delay, I think about this same “upstream” mindset. Construction projects don’t delay because of one sub missing their submittal deadline, or one owner’s rep missing an important email, or one architect taking too long to return a submittal. They delay because of thousands of small “upstream” actions that aggregate into bigger problems that delay the project downstream. In my opinion, if we want to overcome these types of delays, then more and more time, money, and energy need to go into the Preconstruction phase of the project. There needs to be more incentives for doing good paperwork, more collaboration between stakeholders, and more investment into architect, engineer, and GC fees. In other words, develop healthier “upstream habits” that lead to more effective downstream results. It’s really easy for me to say all of this when I’m not the one holding the purse as an owner, and I realize that, but I truly believe that this early investment will pay for itself over the course of the project. Skyline Facades: Matt, when I asked you the question, I had in mind a more conventional answer related to projects delay. I really love your point of view; it does put the issue in a different framework. What would you think hinders the whole process from this “upstream mindset”? Matt: I think the focus on initial cost vs. project life-cycle cost hinders the upstream mindset. Humans like to have the lowest initial price without realizing it may not lead to the lowest final project cost. Skyline: You mention above the need for more collaboration between stakeholders. From your experience, in the majority of the projects you have worked, do you feel the mentality of teamwork between stakeholders or it is more of a “power and muscles” relationship between the parties? Matt: It depends on the project. One thing is for sure: it trickles down from the top. When an owner is collaborative, the whole project is collaborative. When the owner is hard, the project is usually hard. Skyline: How many times have you really listened the phrase “we screwed up” from any project stakeholder instead of just putting the blame to others? Matt: I hear people say it a good amount. Realists know that construction comes with its fair share of mistakes. It’s just how the industry works! Skyline: What is the point when you simply say “ok, this project is not for me” and you just step away? Matt: Usually when the client doesn’t do what they say they’re going to do more than one time. Usually after 2 or 3 instances where they make a promise that they don’t keep, I know I can’t trust them throughout the project either. Skyline: What’s your mantra for today? Matt: I will be kind, compassionate, and caring with myself.

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Chat GPT: Facade Engineering Blog Post

America, Blog /

We are inviting Chat GPT to contribute in our Facade Engineering Blog. Below, is what the Artificial Intelligence software prepared for our blog. A Questions & Answers session follows, as we decided to challenged Chat GPT on what it says, as well as to encourage it to be as specific as possible. Facade Engineering is an important aspect of building design that deals with the design, construction, and maintenance of building exteriors. The facade of a building not only provides aesthetic appeal but also serves functional purposes such as waterproofing, thermal insulation, and acoustic control. In this blog, we will explore the basics of Facade Engineering, its importance in building design, and the key factors to consider when designing a facade. Importance of Facade Engineering The facade of a building is its public face, the first impression that visitors, tenants, and passersby have of the building. A well-designed facade not only enhances the visual appeal of a building but also reflects its character and identity. Moreover, the facade serves as a protective barrier against the elements, noise and pollution. A properly designed and constructed facade can improve the energy efficiency of a building by reducing heat gain and loss, thereby reducing heating and cooling costs. Additionally, the facade plays a crucial role in providing natural lighting and ventilation, which can enhance the health and well-being of occupants. Factors to Consider in Facade Engineering 1. Function: The function of the building is a crucial factor in designing a facade. A commercial building may require a facade that showcases its brand identity and attracts customers, while a residential building may require a facade that provides privacy and security. 2. Location and Climate: The location of the building and the local climate are important factors to consider when designing a facade. The facade should be designed to withstand the local weather conditions such as wind, rain, and snow. In addition, the facade should be designed to optimize natural lighting and ventilation while minimizing heat gain or loss. 3. Material Selection: The choice of facade material plays a critical role in determining the durability, energy efficiency, and aesthetic appeal of the building. Some common facade materials include glass, concrete, brick, stone, metal, and wood. Each material has its own set of advantages and disadvantages, and the selection should be based on the function, location, and climate of the building. 4. Structural Design: The structural design of the facade should ensure the stability and safety of the building. The facade should be designed to withstand the loads imposed by wind, snow, and seismic forces. The structural design should also accommodate the movement of the building due to thermal expansion and contraction. 5. Maintenance. The facade should be designed to minimize maintenance and repair costs while maximizing the lifespan of the building. The facade should be easy to clean and maintain, and the materials should be durable and resistant to corrosion, weathering, and other forms of degradation. Conclusion Facade Engineering is a crucial aspect of building design that requires careful consideration of several factors such as function, location, climate, material selection, and structural design. A well-designed and constructed facade not only enhances the visual appeal of a building but also improves its energy efficiency, provides natural lighting and ventilation, and protects the building from the elements. As such, it is important to work with an experienced and knowledgeable facade engineering team to ensure that your building’s facade meets your functional, aesthetic, and sustainability goals. Q & A Session Skyline Facades: If it is OK with you, we would like to ask you some questions on this very interesting blog. What do you mean by location and climate to be considered in Facade Engineering? Chat GPT: Location and climate are two important factors to consider in facade engineering because they can have a significant impact on the performance and durability of the building facade. Location refers to the geographic location of the building, and it can affect the local building codes, regulations, and standards that must be followed. For example, buildings located in areas with high seismic activity may require special structural designs to withstand earthquakes, while buildings located in areas with high wind loads may require special facade designs to resist wind pressure. Climate refers to the local weather patterns and conditions in the building’s location. Climate can affect the thermal performance of the building facade, as well as its ability to withstand weathering, corrosion, and other forms of degradation. For example, buildings located in areas with high temperature and humidity may require special facade designs to reduce solar heat gain and minimize the use of air conditioning systems. Similarly, buildings located in areas with high levels of precipitation may require special facade designs to prevent water infiltration and protect the building envelope. Therefore, in facade engineering, it is important to consider the location and climate of the building to ensure that the facade is designed and constructed to withstand the local environmental conditions and meet the specific needs of the building and its occupants. Skyline: Let’s be more specific on climate. So let’s assume we have a building in Dubai and an identical one in London. What are the factors to consider? Chat GPT: If we compare a building in Dubai to an identical one in London, there are several factors related to climate that would need to be considered in facade engineering: 1. Temperature: Dubai has a hot desert climate, with temperatures often exceeding 40°C during the summer months, while London has a temperate maritime climate, with average summer temperatures around 22°C. In Dubai, the facade would need to be designed to reduce solar heat gain and control indoor temperatures, while in London, the facade would need to be designed to provide thermal insulation to maintain indoor temperatures. 2. Humidity: Dubai has a low humidity climate, while London has a higher humidity climate. In Dubai, the facade would need to be designed to minimize moisture infiltration and condensation, while in London, the facade would need

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Facade Structural Engineering

Steven Sletten: Insights into Facade Structural Engineering

America, Blog /

Today’s guest is Steven Sletten, a Licensed Professional Structural Engineer and Project Manager for Larson Engineering in New York. Steve has great experience in the Façade and Curtain Wall Industry and has licenses from New York and Minnesota states. Has been involved in many great projects such as Transbay Transit Center, the Star Statue at Mall of America, Lantern House on NYCs Highline, One Madison Ave in NYC and many more. Works for Larson, one of the biggest firms in the field with 11 offices across United States. Skyline: What are the important items in a Facade Structural Reports and where do you give the most attention?  Steven: There are many important aspects of a façade structural report that bear mentioning.  The most critical items that should never be overlooked or discounted, are those pertaining to design loads and applicable building codes/standards.  The codes used today are established to provide an appropriate level of safety factor, in order to ensures a design is safe.  There are aspects of the design and engineering that can be up to the engineer’s judgment, however the minimum standard of care should always be to meet or exceed load/building code requirements. The second most important aspect, in my opinion, is providing an efficient design that will meet the project specifications.  This includes working closely with the client (fabricator/glazier/etc) to determine any project specific design criteria or specification requirements, including serviceability limit states, that may impact the design. These are important as they impact the clients’ bottom line, as well as owner satisfaction with the end product.  If specifications are not met, there is potential for the owner rejection resulting in rework or potential back charges to the client. The engineer’s goal should be to have an efficient design.  The project may have high corner zone wind pressures, but may only occur on a small percentage of the building.  It may be possible to get by with reinforcing system(s) only in corner wind regions, or maybe the loading is high enough in all regions, such that a change to the system extrusions/depths is warranted. Additional engineering time spent may be well worth the effort in order to provide the most efficient design for the client. Considering the additional cost of labor and material resulting from an excessively conservative or quick engineering design, may far exceed the cost associated with a more thorough engineering design. Each aspect of the overall design, should be reviewed with respect to the project specifications, applicable codes, and consideration for both the engineering and client budget. Skyline: Are the specifications and wind loads getting over-designed? Steven: Wind and code loadings are an ever-changing topic in the structural engineering industry. As more testing is executed, and more information is learned by the code agencies, the more accurate the resulting requirements become. This is paired in the facade industry with the need to be as efficient in design as possible.  These factors combined have led to our current codes and results in wind loads being dependent on many project specific factors, including but not limited to:  project profile (Manhattan skyscraper versus two-story building in Iowa), project complexity (unique building footprint vs box building), project location (Suburban area in Pennsylvania vs the coast line of Florida), applicable building codes for the project location, and also overall building design/construction. Typically, if a project is a low profile, simple building, the design wind loading for the project, likely wouldn’t be much different from older to newer codes much from older building codes. Skyline: What software you use for Facade Structural Reports? Steven: Wind and code loadings are an ever-changing topic in the structural engineering industry. As more testing is executed, and more information is learned by the code agencies, the more accurate the resulting requirements become. This varies within in the industry, but typical software includes: – Mathcad or similar engineering math software which is used in the creation of many calculation templates. – Use of Microsoft excel sheets, can be used in similar fashion, but may not be as friendly to the reviewer. – RISA or other similar 2D/3D structural analysis software. – RFEM or other Finite Element Analysis software. – AutoCAD or similar drafting software. – Bluebeam Revu or similar pdf editing software. Depending on your firm / expertise, you may have other complimentary software as well, used to support thermal analysis, acoustic analysis, etc. Skyline: What is the typical academic background for a Facade Structural Engineer? Steven: It is standard that a Facade Structural Engineer will have at minimum a Bachelor’s degree in Civil Engineering – Structural emphasis.  It is also common for some firms to require a Master’s degree. Most engineers will have completed and passed the EIT exam, either prior to starting full-time, or during their first years as an engineer.  Most engineers will go on to take either the PE or SE exams for their respective state, and other states as required for the company/position. Skyline: What is the most challenging project you have worked and why? Steven: The most challenging project so far in my career, was a façade replacement for a high rise in New York City.  Due to damage on a portion of the elevation high up on the building, there was a need to remove and replace multiple bays of curtain wall system in an occupied building. The project was a testament to collaboration, as there were no drawings provided from the building owner, and also required to get an exact match to the adjacent existing curtain wall.  Careful consideration for site access and safety was maintained throughout the project, and the final product met all project requirements.  To this day, an unknowing eye, will most likely not be able to see that anything had been replaced. Overall, it was an exciting and challenging experience, as we spent more time than normal coordinating directly with members of the design team, the project building envelope consultant, and also a contracted façade designer that aided in all of

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Ventilates Facades

Ventilated Facades, Fire Safety: No need for a zero-sum game

Blog, Europe /

The concept and the history of building ventilated façades is not something novel. Actually the first examples of building facades are met in medieval Europe. Wood was the dominant material for the construction of facades since it was easily sourced from the vast forests that existed in Western Europe during this historical period. West Stow, Suffolk | UK – 5th– 7th Century AD (Building Reconstruction – Archeological Site If we try to find a benchmark project in contemporary building, we could arrive at no other than Flatiron Building in New York since it used metal structure and cladding. A significant parameter for the design of Flatiron has been the revision of the New York Building Act in 1892, which abrogated the requirement for masonry on the ground of fire safety reasons and gave rise to the formation of plenty of the modern building methods. Namely, the creation of a shell, which is suspended through a secondary level of support system on the primary frame of the building. In the case of Flatiron Building, glazed ceramic panels are the dominant cladding material of the facades. Flatiron, New York | USA – 1902 Today, the usage of ventilated facades with the simultaneous integration of a multitude of different materials –natural and artificial, such as metal, glass, ceramics, concrete, composite wood, plastics etc. has prevailed worldwide. Naturally, the progress in the field of materials science has been an important factor for the realization of the modern building. The Beam on Farmer, Phoenix AZ | USA (Aluminum Panels) The ventilated façade is synonymous with the structure of a multi-layered shell. A key feature of the ventilated façade is the clear separation of structural elements that are in direct contact with the interior or exterior space, as follows: – External cladding – Air gap – External insulation – Internal masonry The creation of air gap throughout the height of the building, in which the circulation of air remains unobstructed, but at a higher temperature than that of the natural environment, implies the circulation of air in conditions of natural attraction. Briefly, the air enters the gap, is further heated by the absorbed solar radiation and is emitted by the cladding, moves upwards, creates a vacuum, which tends to be filled again with air and hence continuous ventilation is ensured within the shell. Results of external thermal insulation and natural ventilation can be summarized as follows: – Improving thermal comfort in the interior of the building. – Saving energy for both heating and cooling, through the reduction of thermal losses. – Protection against moisture, as the external cladding is a first protective level while at the same time ventilation accelerates the removal of residual moisture. The three axes for the sustainability of buildings as below: – Limitation of the environmental footprint (Construction – Usage) – Ensuring the optimum operation of the building over time. – Enhancing the comfort levels for its users. The fireproofing principal of the ventilated façade as a fire transmitting factor The fundamental operating principle of the ventilated façade is at the same time its weakest point in terms of fire transmission. The natural attraction of the air within the façade dramatically accelerates the vertical fire spread of fire, consequently facilitating its expansion throughout the building. In this way, even a small localized fire can potentially evolve into a large scale fire to the whole building. Grenfell Tower in London has been the most notable case of building fire since several decades. A residential building of 24 floors, initially erected in 1967 and renovated in 2015-2016 with ventilated facades cladded with LDPE Aluminium Composite Panels and insulated with PIR. The non-compliance with Fire Regulation act was considered as the root cause for the tragic death of 72 people. A typical example of the fire spread in Grenfell Tower was while the first fire hearth was detected on 00:54 and by – 01:30, the fire had reached the roof of the building through vertical transmission and was totally out of control. Istanbul / Turkey Vertical fire expansion in 24-storey building. It is worth noting that while the building seems mostly unharmed, there is a vertical fire across the entire side of the building with possible disastrous effect. Tackling Design Methods (Fire-Barriers and Fire Compartmentalization) It is possible to maintain the advantages offered by ventilated facades while ensuring fire protection. The placement of fire barriers horizontally and vertically in order to fire compartmentalize the façade in accordance with the General Fire Safety of the building answers the existing challenge. A fire barrier is placed horizontally with fire-resistance sealing tape, leaving a gap of 25-50 mm from the surface of the cladding. In this way, the ventilation of the façade is ensured while it is interrupted in the case of fire. (1) Complete vertical fire barrier (compressed Rockwool in aluminium shell. (2) «Open» horizontal fire barrier with fire-resistant sealing tape. (3) Fire-inflatable sealing tape. Example of Facade Engineering Study as above. In this case, and in the particular Unitized System with embedded brickslips, we can see the vertical fire-barriers at the side of the unitized module and two vertical fire barriers with the fire-inflatable membrane. Re-defining the proper function of facade in existing buildings Case study with residential complex in Stratford, London built in 2006-2007. In 2021 it joined a State Funding Program in order to harmonize with the Fire Protection Regulation. The Grenfell building tragedy has triggered the imperative to carry out checks regarding the provided safety of buildings in Great Britain. The range of interventions required is extensive, both in terms of replacing the materials of the facades with fire-resistant ones, as well as in redesigning the shell by creating fire compartments. The materials replaced are: – Aluminium Composite Panels with 3mm Solid Aluminium Sheets. – Wood cladding sheets with fibrocement sheets. – Wooden decking floors with aluminium ones. – External thermal insulation system with corresponding non-flammable. – Spandrel glass curtain panels with corresponding with non-flammable core. – Brickslip cladding due to absence

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Ph.D. award to our Anastasia Sakka

Europe, News /

We are very proud for our Projects Director and Principal Anastasia Sakka, who has just received her Doctor of Philosophy degree in Architecture from the University of Edinburg in Scotland. It was a beautiful journey that started 10 years ago and was officially completed yesterday in a traditional ceremony, so typical for UK universities. After all the hard work that Anastasia has put in, she sure deserves the highest degree that a student can have. It is a great success for Anastasia and her family  (yes, that includes us also -), having proved again how dedicated and strong-willed she is. A Ph.D degree is much more than a mere gain of a qualification to be proud of; it is also the incredible experiences along the way. Our best wishes to our lovely Principal for the future -)) We should not forget to express our sincere gratitude to the best supervisor we could have, Professor Iain Boyd Whyte. #facadeengineering #greece #skylinefacades

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Facade Structural Engineer

John Wheaton: a 40-year Journey on Facades

America, Blog /

Today we have the honour to host in our blog John L. Wheaton, CEO and Co-Founder of Wheaton & Sprague Engineering in Ohio. John is a legendary figure in facade industry, having engineered, consulted or directed on thousands of exterior cladding projects.  Including custom and standard curtain-wall systems, panel systems, stone facades, architectural components and most other types of exterior wall systems across United States and Caribbean. He is Structural Engineer by discipline and Professional Engineer in multiple States. Additionally, John is the host of the fabulous podcast Creating Structures (https://creatingstructure.buzzsprout.com/) featuring interviews and discussions about life, business, architecture, construction and more. The podcast is available on all favorite podcasting platforms, I personally prefer to listen it through Apple podcasts. Skyline: John, you are in this business for almost 40 years now. During this period, we have experienced 5 or 6 downward economic cycles. What is the relation of construction cycles relative to those in general economy? JLW: In our space we are at the tail of recession cycles. It’s seen first in retail, consumer goods, and similar, then other things downstream like home purchases, new home construction, then on and on until it hits the commercial construction space. We have long lead times to assess and monitor what is happening in the markets by being at the tail end of the downturns, typically. Through the process it’s expressed in fewer RFP’s, more competition, less work over time. We typically have been 12 months to 18 months behind, since many projects, once started, have to go to completion. This isn’t always the case, since all cycles of downturn are unique, but construction and specialty subcontracting is at the back end however long it takes to get there. Skyline: Many of the businesses in our field are family ownership and management. How do you see the performance of those businesses over time. JLW: The truth is that most business are privately held in general. All privately held businesses are “family businesses” (private money put up by someone that is at risk). My view is that it runs from poorly managed to well managed depending on may factors. Privately held “family” businesses, whether simply financed by private ownership with a management team or owned and operated by private ownership with a management team supporting, can be well managed or poorly managed. It depends on the level of function or dysfunction in the leadership. All companies rise and fall on the strength of ownership, and how they think, conduct, operate, finance. Skyline: Do you predict that the use of Revit will replace traditional AutoCAD in the near future. JLW: I am not big on predictions, but I have been both in the forefront and the backend of this question about the shift to REVIT. The question is broad and the answer depends on what context we work within. REVIT has been and is replacing traditional AutoCAD at many architecture companies. However, it will not replace AutoCAD in near future in the glass, glazing, façade, curtain wall space. Professional services firms, contract glazing companies, and architectural fabricators all use their own approaches. I know some that use RHINO, some AutoCAD, some REVIT in part or in full, and some INVENTOR. Some use a combination of all or part of them. It just varies based on the application, people, training, processes, and other factors. No one software fits all applications. They are all just “tools in the toolbox.” Skyline: We see lately bigger and bigger openings in buildings, let it be cladding panels or glazing. What challenges does this imply for structural engineers?  JLW: Bigger openings, taller, wider, panel, glass, infill, cladding materials, just make more opportunity for structural engineers to help support and inform the process. The challenges can lie in various areas on how it influences required system depths, anchorages, connections, and performance criteria of the “panel” itself. Some clients don’t think through the cause-effect relationship of how the bigger opening or cladding material may affect the framing that supports it. I like that things are “pushing the envelope” with ever increasing measure and exploring the limits of materials. It creates opportunity and value for those brave enough to step into it. Skyline: What is the real value of PE stamp for engineering. JLW: Well many may be surprised to hear me, as a professional engineer (PE), say this but there is no intrinsic value to the PE stamp alone, but in the knowledge, approach and integrity of the PE overseeing or executing the work. Fundamentally, the PE stamp is supposed to have value to a project in validating that the work is engineered according to the appropriate standard of care, performance criteria for the systems, and for the benefit of the health and welfare of the occupants, public or users. There should be a strong risk mitigation component that brings confidence to the client and all constituents that engage touch or use the building or systems supported by the PE stamp. But the PE stamp is only as good as the PE behind it. PE’s do much to make the world a better place, much of which is not recognized. Approached properly, a client should receive not only the peace of mind that the PE’s stamp certifies the integrity of the system, but that they also provide client-centered or client-specific value that is expressed in the cost-to-value ratio. This can be manifested in various ways such as material or labor optimization, simplifying design, reducing complexity, communicating clearly, and more. Skyline: What is a project that you really feel proud of? JLW: I feel proud of every project we do and complete. Some notable projects include University of Baltimore Law Library in Baltimore, MD, Rainier Square in Seattle, AJ Celebreze Courthouse in Cleveland, Ohio, University of South Florida Judy Genshaft Honors Building in Tampa, Florida, the RUFUS (Amazon) HQ buildings in Seattle, and many, many others across the USA and in the Caribbean.

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Unitized Systems

Curtain Walls: Is a Unitized or a Stick System Better for Buildings?

America, Blog /

Definition for Curtain Walls can be as non-structural aluminium framed walls, containing infills of glass, stone or metal panels that are connected on the building structure. They can be broadly categorized into Unitized Curtain Walls and Stick Built Systems. The question of whether to opt for the one or the other, is a very common discussion in our Façade Engineering world. And as with most things in life, the answer “it depends”. Let’s try to examine below the parameters that can affect this decision. Left: stick system with exploded transom —- Right: exploded unitized system 1- Facade total size. The larger the facade is, the more arguments can be found in favour for the unitized. It will mean less total cost (*under certain circumstances that we will see below) and higher speed of installation. In a typical all-glazed building, for a standard curtain wall, the borderline for a unitized system to be developed and make sense is around 5.000 m2. For less than that, stick systems tend to be preferred as they will be more economically viable. Midtown Sports Complex, Tel Aviv, Israel 2- Repetition degree. When the height of the floor is constant and the distance between the mullions repetitive -what is called in our field as the “typical floor”-, it is sensible to break the façade into units of similar size. Prefabrication at the factory will take place, trucks will be loaded and transported to the site, installation will be completed with glass, spandrel elements and gasket, at a much faster pace than proceeding one stick at a time. Ah don’t forget, without the need of scaffolding as well. An important advantage of unitized systems is that most of the work is carried out in the factory. This simply means better control and without possible environmental adverse conditions like wind, rain or  snow. As we all know, 80% of the mistakes, will happen on site. 3- The building planarity. If the project has flat and vertical walls, stick systems are easy to assemble. This is not the case with complicated slopes and 3-D shapes, where unitized take the lead. Unit prefabrication, assembled in the factory, sealed in the factory and interlock joints so you can allow for on-site adjustments. And when more brackets are required for external sunshades and fins, it is better to produce them in the factory as a unit system. 4- Dimensions and shapes. Unitized systems are better suited to be used in high buildings (above 6-storeys) due to the shorter required installation time. Larger panel and glass dimensions also favour unitized. This is not the case with low and extended buildings that offer an easy to access façade from outside. Actually, the vast majority of low to mid-rise curtain walls globally are installed with stick facades and there are very good reasons to do so. Karel De Grote University, Antwerp, Belgium 5- Building Location. Having worked in many international cities and markets, we have observed major cost differences that can affect the overall decision. Material costs present minor differences among countries or even continents. However, labour costs tend to vary heavily among countries and wages in  USA are several times multiple in comparison to wages in some Eastern European or Middle East countries. Value engineering exercises have shown us that a certain building can be more economical in USA with unitized system while an identical building in size, height, geometry and complexity can be more economical in e.g. Romania with a stick system. And by far. We have found differences –though in much smaller degree- even within the same country, for instance a tower in New York City has different building economies versus a mid-town tower in a typical US Southern state capital. Another issue to be addressed, is the availability and relevant expertise of façade subcontractors. It is a universal fact that the pool of subcontractors with stick curtain wall systems proven experience is much larger than the similar pool with unitized systems experience. In countries like USA, Arab Emirates or Germany, there will still be a reasonable number of bidders. But in other countries like my native Greece or Cyprus, there is no more than a handful or even none such subcontractor. Bottom line We believe that the use of unitized wall systems will increase in the coming years, mainly due to two main drivers. The one, is urbanization. Recent studies have shown that by 2050, 70% of global population will live in mega-cities. And since land in those cities is more or less for granted, we expect to see larger and taller buildings. The second, is the ever more complex shapes that we see in modern architecture in all parts of the world. As the number of city towers increases, so does the competition between the developers to attract the wealthier tenants and buyers. The more unique design architecture wins and the last years we have seen designs and structures that seemed impossible a few years back. Majdoul Tower, Riyadh, Saudi Arabia Cayan Tower, Dubai, Arab Emirates   Bibliography – Analysis and design of unitized curtain walls, Stefano Cascone 2016, Mediterranean University of Reggio Calabria, ResearchGate. – Abul Abdullah, Marius Ronnett, 2010. Explanation of Curtain Wall Solutions, Perkins + Will Research Journal, 2010, 2, 33-55. – Khoraskani Afghani R., 2015. Advanced Connection System for Architectural Glazing. Milano: Springer, 2015, 125p. – Mc Farquhar Dudley, 2012. The Role of Building Façade. Building Enclosure Technology & Environment Council (National Institute of Building Sciences), 2012. – Patterson Michael R. 2008. Structural Glass Facades: A Unique Building Technology. Ph.D Thesis, University of Southern California Faculty of the School of Architecture, 2008 – Taywade Pallavi, Shejhal Santosh, 2015. Structural Design of a Glass Façade. International Journal of Scientific and Research Publications, 2015, 5, pp 1-6. – Tillman Klein, 2013. Integral Façade Construction. Architecture and the Built Environment, 2013, 3. – Ignacio Fernandez Solla / Director, Arup. – Should I Use a Unitized Curtain Wall of Stick-Built System? W&W Glass

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