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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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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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Petko Pachev for Fire-Rated Windows

Blog, Europe /

Petko Pachev is a leading figure in the aluminium market of Bulgaria and an expert in all kinds of extruded products. He has more than 17 years of experience in the fields of business and product development of aluminium systems. Today, we are seeking for his experience in Fire Rated Systems for Windows and Doors. What are fire-rated systems? Those are systems that are used in fire protection and evacuation areas in buildings. The most common types are made of steel or aluminum. The steel systems are mostly used in places where the design and appearance are not the main goal while the case with aluminum solutions is the opposite. The Aluminum systems with FR glass fillings are much more aesthetic and add value to offices and residential buildings. What EI-60, EI90, EI120 etc. means? The EI means integrity and insulation. E – Integrity. This is the ability of the system to stop fire from spreading to an unexposed side as a result of penetration of flames or smoke. I – Insulation. This is the ability of the system to restrict the temperature rise of the non-heated side to below specified levels during the fire. All the above-mentioned symbols are followed by as a time limit in minutes. The number after a given symbol shows the time the performance criteria is fulfilled during a standardized fire test.      Ex: EI30, EI60, EI90 etc. Do such systems need special equipment / knowledge by subcontractors? The production of aluminum fire-rated systems is almost the same as the solutions with non-FR classes yet there are some very specific machining, assembly and installation processes that are far more complex and require specialized knowledge and accreditation. The main differences are the following: The fire-rated systems are much heavier than the standard ones therefore special equipment for handling and transportation is required. It takes more time for machining and assembly of the fire-rated systems. Is there anything else subcontractors should have in mind concerning fire-rated solutions? It is very often that I see inquiries for very big dimensions of fire-rated glasses and subcontractors should have in mind the heavy weight of the fire-rated glass. For example: EI60 glass weight is around 45kg/m², EI90 glass is around 50kg/m², EI120 glass is around 60kg/m². Decision makers should think about situations when a glass need to be replaced when the building is operational. In cases where aesthetics is a must I advise my partners to use fire-rated solution with silicon gap on vertical instead of aluminum profiles. I also recommend to subcontractors to choose fire-rated glass with the longest warranty period as the glass cost is among the most significant in the final product. Finally, and not least importantly, the decisions about fire-rated systems should be taken always having in mind that those solutions are intended to save lives.

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Fire Safety

Fire Safety and Fire Strategies by Abhishek Chhabra

Blog, Middle East /

Abhishek Chhabra is an Engineer and a Post Graduate Diploma holder in Finance. He advocates the need for compliance to standards for improved Fire Safety and Quality across industries for most of the last two decades. He has vast experience of promoting conformity assessment in several industries. He has worked on several Standards and Codes development initiatives, specifically with Bureau of Indian Standards (BIS), ASTM, UAE Fire & Life Safety Code of Practice and Saudi Standards, Metrology and Quality Organization (SASO). He joined Thomas Bell-Wright International Consultants in 2013 and has been the driving force behind the expansion of the Fire Compliance activities. He also owns and drives a blog and a LinkedIn group called Gurus of Testing, Inspection and Certification (www.tic.guru) aimed at expanding the understanding of conformity across the world. What is the critical factor in determining the fire-safety of a glass façade? The starting point to answer this question is the occupancy type of the building which has a glass facade. The type of building (mall / school / hospital / residential tower / office complex, etc.) is what dictates the readiness of the people whose lives in would be in danger in case of a fire and what else might be at risk of the fire. These are among the several key factors that form the basis of Fire-Safety strategy or plan. They help formulate building regulations or guideline documents (Building codes) which are used in more evolved regions in the world. A glass facade like most of the facades have replaced what used to be traditional load-bearing walls more than 50 years ago. They used to undertake several functions as in the image 01 here.  These functions as often undertaken by several components. The key fire safety strategy (of passive fire protection) is implemented by compartmentalizing a fire within the place where it originates. When the building has a glass façade the most important considerations in ensuring fire safety is compartmentation. This is realized at the floor to wall joint (spandrel section) to ensure that the fire can be contained within the floor and does not break into the floors above or below. Fire propagation across the fascia of a pure glass facade is only a matter of concern when there are other elements across the glass facade that could carry a flame or a fire. In certain occupancy types the glass facade also needs to act as the fire containment wall and here these is a fire rated glazing system. We know that the permutations and combinations of raw materials or components that build up a glass facade can be really large. So it becomes critical that assurance mechanisms of the supply of raw materials and components as well as workmanship of installers are very stringent! What is the individual rating of the components of a typical glass facade, i.e. glass, aluminium, silicone etc.? The individual response of components like Glass, Aluminium (Grade), Silicone, etc. in a fire or a scenario that could create a fire is very important (For Glass facades and not for other cladding types). But these individual (reaction to fire or resistance to fire) ratings are meaningless without the assessment of a system behavior. This is part of the steep learning curve that industry and governments have been imbibing in recent times. Reading further from the initial question’s answer then, the real proof of performance of these components for Fire Safety lies only in how they behaved when they are part of a system. The tests would typically be Fire Resistance test used for evaluating compartmentation (ASTM E2307, ASTM 2874, EN 1364-3, EN 1364-4, etc.). The small-scale reaction to fire classifications like as per EN 13501-1 or ASTM E84 then are only indicative of how they could contribute or react to a fire or fire like environment. Does the paint on aluminium contribute on fire? And what about anodization? Pure solid metals when used a facade material are very harmless from a Fire Safety perspective as they are non-combustible. But coatings and paints take these into a different direction. Any organic compound used would have a propensity to contribute to a fire due to its chemical composition. Hence Solid Metal Facade Materials initially thought to be very safe started being reconsidered as they were getting tested for reaction to Fire Classifications. I can share that just because of the what is on a Solid Metal Cladding Sheet, the Reaction to Fire properties could be class B or C or worse even. Refer to Image 02 for better understanding of these Classifications. As for anodization the answer is straight: as long as no organic compound is coming on-to a metal; we are ok. We see that countries have many different fire regulations. Does it happen that a particular assembly / product achieves the highest rating in one country but is rejected in another? Unfortunately, the answer is no. And that is mainly because there is not world-wide agreement on what is highest rating! Can you tell us a few things on full scale fire tests? What is the difference between e.g. NFPA 285 and BS 8414? This is a tough to try in a small post as they are completely different approaches to evaluate fire propagation performance. To start with the geometry and mock-up configuration are completely different. The list continues on mock-up methodology, type of ignition source; measurement methodologies as well as assessment of pass or fail. But this is the case with 20 plus test methods that have been evolving around the world. And unfortunately, more are evolving and getting published. While both these methods have been revised recently, I must share that the BS 8414 Test Methods are only Test Methods. They utilize another published document BR 135 to assess the results of the test method to give an opinion on weather the mock-up system should be considered safe or not. This document, the BR 135 (Fire performance of External Thermal Insulation for Walls of Multi-storey buildings)

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Powder Coating with Khalid Shamlawi

America, Blog, Middle East /

Khalid Shamlawi is the Specifications Manager for Jotun Powder Coatings and looks after UAE region as well as Oman, Kuwait, Bahrain, and Egypt. Among his duties is to establish and maintain strong relationships with key upstream clients and project owners to influence specification decision-making at the project management cycle. He’s a keynote speaker for all events in the region with expertise in Powder Coating. Jotun has been developing paints since 1926 and is now one of the world’s largest paint companies. Today, the group comprises of 67 companies and 40 production facilities across the world and employs more than 10.200 dedicated employees. Which type of paint you consider better, powder coating or PVDF? They are both good options, no question on that. For me, it is powder due to the following reasons. VOC contents are negligible for powder, while it is moderate to high for PVDF. You can achieve the required result with powder with a single coat, while you will need up to 3 to 4-coats for PVDF. Colour consistency is easier to control with powder, with PVDF is much harder to control. Easier process for the user. There are a much larger large number of approved applicators for powder coating. Guarantee comes at 25-30 years for all colours of powder, for PVDF is quite vague as it depends a lot on specifications. There is a richer finish on powder. What about anodization? Anodization used to be dominant in our industry but these days belong to the past as its share constantly declines. Main reason is the inconsistency of colour, it is very difficult to control. This is due to variance of metal constituents, temper, anodizing tank chemistry, shape geometry and material load size. As the world becomes more environmentally conscious, we are moving towards healthier practices. Anodizing has low friendliness, there are concentrated acid baths (vapour concerns) and waste disposal concerns. Further reasons that anodizing market shares continues to decline is the very limited colour and finish choices and the high resource consumption. What is the optimum paint thickness for powder coating?   We measure dry film thickness as per Qualicoat standards. In the final assessment, none of the measured values shall be less than 80% of the specified minimum value otherwise the thickness test as a whole will be considered unsatisfactory. The results shall be assessed as shown by four typical examples (minimum thickness for coatings of 60 μm): Example 1: Measured values in μm : 82, 68, 75, 93, 86 average: 81 Rating: This sample is satisfactory. Example 2: Measured values in μm : 75, 68, 63, 66, 56 average: 66 Rating: This sample is good because the average thickness is more than 60 μm and because no value measured is less than 48 μm (80% of 60 μm). Example 3: Measured values in μm : 57, 60, 59, 62, 53 average: 58 Rating: This sample is unsatisfactory and comes under the heading “rejected samples. Example 4: Measured values in μm : 85, 67, 71, 64, 44 average: 66 Rating: This sample is unsatisfactory although the average thickness is more than 60 μm. The inspection is unsatisfactory because the measured value of 44 μm is below the tolerance limit of 80% (48 μm). Across different markets and climates, the choices of material for windows varies. In Northern Europe PVC is dominant, while as we move to Mediterranean countries and Middle East, aluminium takes over.   There is no question, aluminium is a far better material than uPVC. I can sum up advantages as below. Much more durable. An aluminium window has lifecycle of more than 60 years while uPVC is approximately 25-40 years. Maintenance. Aluminium does not crack, peel or rot and there is ease to change a broken glass by removing the glazing beads. uPVC on the contrary is a very soft material that can easily get scratched while you have to exchange the whole vent frame if glass is glued in for stability. Aluminium has high stability due to great strength to weight ratio and high wind as well as burglary resistance. uPVC needs steel or aluminium reinforcement steel to reach the same stability in same sizes. There is great colour variety in aluminium through powder, liquid or anodizing. On the other hand, there are only limited shades of whites, greys and browns and not all uPVC is UV resistant which leads to colour fading. There is lot of discussion lately for fire safety and regulation. This debate is global since there are several incidents with fires in building. Does paint contribute to fire performance and how much? We need to be able to interpret the fire classification test results. The latest Dubai Civil Defense Regulation has adopted European Standard EN 13501-1. A typical classification comes as e.g. B – s1- do. Let’s see what this means. First digit is the reaction to fire classification which determines how much (if any) a building material contributes to the spread of fire. Class A1 – A2     = non-combustible materials. Class B, C, D        = ranges from very limited to medium contribution to fire. Class E, F             = high contribution to fire. The “s” part relates to the total smoke propagation, during the first 10 minutes of exposure. These determine a “smoke” index: s1 = little or no smoke. s2 = quite a lot of smoke s3 = substantial smoke. The “d” part relates to the flaming droplets and particles, during the first 10 minutes of exposure. d0 = none. d1 = some. d2 = quite a lot. According to EN 13501-1, Jotun Super Durable paint fall under A2-s1,d0 category, while Jotun Durasol is plain A1.

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