Building Enclosure Consulting

Facade Doctor

Glass Experts

Introduction. If you arrived here, it means you probably need help with your architectural glass. Whether the glass is still in the design stage, or it’s installed in an existing building, or the glass has been damaged, we can help you. Pick the topics of interest from the list below. Feel free to contact us at or one of our telephone numbers listed on our contact list.

foggy glass

Glass and Glazing. We specialize in architectural glazing: architectural glass, curtain walls, sloped glazing, skylights, windows, storefronts, sliding glazed doors, fully glazed balustrades, etc.

For practical purposes, we divide our services in three phases: 1) design, 2) construction, and 3) forensic investigations. In addition to these services, we also provide education for architects, engineers, and building enclosure consultants.

1) Design Stage . In the design stage, we contribute our experience to peer reviews of construction documents. It’s enough to say that we have yet to see a correct architectural construction documentation set with respect to glass and glazing.We review documentation for constructability, compliance with applicable codes and standards, and the current level of building science knowledge. We produce glazing specification. We also provide computer simulations and engineering to determine the best performing glass for your application, including structural glass applications, and double curvatures.

2) Construction Stage. In the construction stage, we assist during physical tests, and monitor installation in the field, respond to RFIs, and assist parties of construction process in understanding technical aspects of glass and glazing. We also verify code requirements applying in a specific jurisdiction. We also provide computer simulation and testing to contractors.

3) Forensic Investigations. In this phase, we investigate the existing conditions of glass and glazing, conduct diagnostic testing, review available documentation, conduct computer simulations, and document our observations and findings. We specialize in high-rise facades characterized by a challenging access. The most typical cases involve cause and origin investigations of scratches, welding damages, collapse, and breakage. We also analyze glass quality and compare observed blemishes with acceptability criteria (architectural specification). We verify code compliance, and technical parameters, such as solar heat gain coefficient (SHGC), visible light transmittance (VLT), and thermal transmittance (U value). We verify entire assemblies with water and air permeability testing. We also conduct computer simulations of failures and damage. We also provide repair and replacement design and specification.

Glass Breakage Investigations. We determine cause and origin of glass breakage, including approximate dating. This is useful for e.g., insurance adjusters veryfing glass breakage claims.

Glass Matching. Glass breaks. In some hurricane-prone areas, like Florida it happens quite often. But seldom all glass on a facade is gone. Therefore, the same questions inevitably arises: how to find a matching glass? Is the expensive replacement of the whole wall necessary to get the matching appearance? Your building official would tell you that you would need a new framing as well, in order to comply with the new building code, and your insurer is going to deny your bill by saying the replacement wasn’t necessary. Some owners get a local glazing service contractor, and the results are telling (see the video below and the picture to the right).

You can save hundreds of thousands of dollars which would otherwise be spent on replacement of the intact old glass not matching the new replacement glass. Careful identification of glass would help you maintain a consistent look of your facade.

We conduct spectrophotometric measurements and simulations to find the closest match for the replacement of an aged damaged glass. See the video below (3MB) describing the service.

Article About Foggy Glass Disease. Looking Through Hazy Windows. Is your window foggy? If so, welcome to the growing club of unhappy owners of the hazy glazing. The “foggy glass disease” can be described as a white discoloration and loss of transparency. This article was written to respond to typical questions posed by those affected by the disease, and is intended to instruct the reader on how to check their glass, sheds some light on reasons why the glass became foggy, and gives some practical solutions. It’s directed to owners, managers, and maintenance crew of large buildings and focuses on an architectural rehabilitation as opposed to new design and construction. Insurance adjusters may find the article useful in separation of damage from preexisting conditions and gradual deterioration.

Link to the full article available free fo charge for your download. (PDF, 8 pages, size 1.44MB). The links allow to download and open selected articles free of charge. However, we need you to leave us your email address in order to download them. Your contact info is safe with us, our privacy policy is here.

Laminated Glass Fogging. If you start seeing some growing whitish spots on your glass, and you are in Florida, you are probably a victim of glass delamination. One of the most prevalent glass defects in Florida is the failure of the glass laminate interlayer, manifested in localized “fogging,” which may be described as a white discoloration and loss of transparency, typically at edges. See also the article above.

foggy glass disease

Severe glass delamination observed at Miccosukee Casino in Miami, FL.

Insulated Glass Fogging. If you start seeing some growing whitish spots on your glass, and you are farther North, you are probably a victim of IGU seal failure. This is normally expected after approximately 10 years due to the production limits. If it happens prematurely, you may be covered under manufacturer’s warranty. See also the article above.

Failed IGU

Condensation inside insulated glass units (IGU) in Cleveland, OH.

Warm Glass Fogging. Do you have trouble looking through your windows, because of the exterior condensation? This is easy enough to identify. Either you have old windows in the South, or you spent far too much on the warm windows installed in the cold or mixed climate.

Failed IGU

Severe exterior glass condensation observed at FLL Airport, in Fort Lauderdale, FL.

Solar Heat Gain and Glare. Do you get sun tan at your desk? Do you need light artificial lighting in a middle of a day because your shades are drawn? Do your eyes hurt because the background is much brighter than your computer screen? Is a building next door sending a “ray of death” into your window? The daylight and glare should be analyzed early in the design stage and addressed by the design. Solar Heat Gain Coefficient (SHGC) of glass should be coordinated with the architectural and mechanical design. The Visible Light Transmittance (VLT) of glass should be tuned to the daylighting; therefore, its specification should be preceeded by daylight and glare analysis of the adjacent spaces. The mechanical design should be tuned to the SHGC and thermal resistance (U factor) of glass. One of the most important and ironically the least known characteristicts of the modern glass is its coolness. The coolness is expressed as the ratio of Visible Light Transmittance (VLT) to SHGC. The best glass approaches the theoretical limit of glass coolness 2. Ask your architect if these analysis were performed. We provide VLT and SHGC measurements in the field, as well as daylight factor, glare, and spectrophotometric glass makeup simulations. Contact us and one of our representatives would be happy to contact you.

Glass Scratches and Other Localized Blemishes:

For Owners of New Glass: Architectural glazing is often the most expensive component of the building envelope. However, certain sizes and configurations of glass blemishes are typically acceptable under the common industry standards. If you are not satisfied with your brand new glazing, we would gladly compare your glass with the architectural specification. Contact us and one of our representatives would be happy to contact you.

For Owners of Old Glass: Glass blemishes are often challenging to fix, and in majority of cases they are simply irreparable. Please verify the glass type you have first (by stamp in the corner, or specialized tools). Heat treated glass and coatings are seldom repairable. If you attempted an unsuccessful removal of blemishes, such as scratches, pits, etc. by a glass service contractor, you probably are ready to contact us for diagnosis. One of our representatives would be happy to contact you.

For Insurance Adjusters: If you are interested in cause and origin of glass damage, such as scratches and breakage, we offer a specialized glass analysis service for insurance adjusters and attorneys. Contact us for a brochure.

Education. We provide AEC education to architects, engineers, and fellow consultants. We have four different seminars dealing with glass and glazing. We also offer our publications free of charge.Read More…

glass seminar

Computer Simulations. We provide engineering and simulations of glazing. Read More…

Therm software

Prediction of thermal behavior of glazing detail.


Prediction of structural behavior of a typical four side supported glass pane. Also a good test to verify competence of your consultant. Just point to a window glass and ask: where peak stresses are generated within the glass? We tested some famous self-professed “glass experts” and they failed the test – they pointed out to the center of the glass and categorically denied when asked about corners.

Why is it important: glass irregularities (e.g. scratches or pits) in the tension areas would be more detrimental to its integrity than in neutral or compressed regions.

glass mismatch

Individual Window – Priceless! Miami Beach, FL


Trivia: Which apartments in this building are unoccupied? Miami, FL


Pyrolitic glass coating fails quickly when subjected to washout from certain cladding materials.


Unusual spontaneous breakage of a fully tempered, heat soaked glass. Heat soaking is supposed to weed out this kind of defect. Columbia University, New York City, NY.


AAMA 501.2 water testing of a unit skylight. New Orleans, LA


Our services – page from the 2006 brochure.


Sample Reports

Although not all our work results are documented in writing, reports generally give a good example of what we do:

All identifying information was blacked out.

Comments Off on Sample Reports

Visual Light Transmittance (VLT) Testing for Turtle Codes in Florida

turtle codes VLT testing

turtle codes VLT testing

Artificial lighting leads young sea turtles away from water, resulting in their demise. Therefore, many jurisdictions in Florida have adopted a Turtle Nesting Protection Ordinance. The intention of this ordinance is to protect sea turtles and other nocturnal animals along the coastline during the nesting season by reducing light pollution. One of the associated requirements is use of a dark vision glass.

How do you know whether your vision glazing is dark enough? You need to test it.

Building Enclosure Consulting, LLC is an independent diagnostic shop, which specializes in  architectural glazing of building facades. We conduct bench and field testing, as well as computer simulations.

We provide field-testing services of beachfront glazing in order to determine the Visual Light Transmittance (VLT 45) as required by Sea Turtle Protection Ordinances. The code requires all glazing facing beaches to be dark enough to avoid wildlife confusion. In practice, the typical old glazing would not meet the requirement, and require darkening. This can be accomplished by many different methods, including installation of permanent insect screens, meshes, nets, storm windows, or replacing the glass. Laminate films are generally not recommended due to deleterious effect they may have on the existing glazing, and their use would typically void the original glass warranty.

Comments Off on Visual Light Transmittance (VLT) Testing for Turtle Codes in Florida

Façade Engineering With Glass – Canned Seminar on 2 DVDs – Coming Soon!

Duration:  4 hrs although your mileage may vary.  The educational seminar runs for approx.  4 hours running time plus introductions and presentations. The original source seminar consisted of 652 slides.

Comments:  seminar about architectural glass, which addresses the typical architectural questions: how to use the glass to achieve the desired architectural goals, and what advances in technology help to shape the modern architecture. Kaz talks about spectrally selective coatings, insulative glass, acoustic glass, security glass, self‐cleaning glass, photo voltaic arrays, anti‐reflective glass, switchable glass, and low‐iron glass, and structural characteristics of glass. He also discusses what old challenges remain, such as misaligned performance expectations, obsolete codes and standards, production size limits, dimensional tolerances, energy and security misconceptions, glare, and life expectancy. He will also discuss challenges that emerged recently, such as cladding two‐directionally curved facades. Proper glass specification that helps avoid surprises in the field would be discussed as well. Daylight and Solar Heat Gain simulation software will be discussed.

Audience: Architects.

Learning objectives:

  1. Participants will be able to categorize fundamental safety considerations though example details and case studies for use in developing their fenestration design.
  2. Participants will be able to identify factors leading to condensation though example details and charts so they can be addressed in detailing fenestration.
  3. Participants will be able to identify the structural aspects of fenestration design though example details and case studies leading for use in coordinating with manufacturers and consultants.
  4. Participants will be able to target areas subject to thermal movement through example details for use in coordinating expansion room with adjacent construction.
  5. Participants will be able to identify key components in curtain wall systems via review of product details for use in properly specifying application of these products in a project.
  6. Participants will be able to identify key components in storefront systems via review of product details for use in properly specifying application of these products in a project.
  7. Participants will be able to identify types of operable windows via review of product details for use in selecting optimal product selection to achieve desired project design and/or programmatic goals.
  8. Participants will be able to identify limitations of doors via review of product details for use in mitigating water, air, and sound infiltration/exfiltration.
  9. Participants will be able to identify reasons for curtain wall collapse via use of case studies so these deficiencies can be averted in future projects.
  10. Participants will be able to identify factors leading to glass blemishes via use of case studies so proper specification is used in future projects.
  11. Participants will be able to identify factors leading to glass breakage via use of case studies to aid in future review of submittals and field conditons.
  12. Participants will be able to identify factors leading to skylight collapse via use of case studies to so these conditions can be averted in future projects.
  13. Participants will be able to identify critical interface areas of parapets via use of case studies and project details so these conditions can be averted in future projects.
  14. Participants will be able to identify critical interface areas of curtain wall-eave transitions
  15. Participants will be able to identify critical interface areas of AC duct-curtain wall transitions
  16. Participants will be able to calculate solar heat gain coefficients via use of site gathered data for use in efficiently designing building improvements.

Table of contents includes:

DESIGN ASPECTS (234 slides)

Transparency – Slides –



adversary forces

energy quiz



Thermal Movements



Fire and Smoke

Sources of info


ASSEMBLIES (152 slides)

fenestration vs skylights

Curtain walls








(BAD) Glass Tower

Curtain Wall Collapse

Glass Blemishes


Skylight Collapse




Wind Pressure Damage

Specification Errors – Heat Resistance


PROCESS (89 slides)

Glazing Schedule

Design Data and Performance Reqs

Challenges of Delegated Design

Tracing Envelopes

Facade Tectonics

Interface Details

Testing Specs

Risk by Location


CASE STUDIES (88 slides)

Parapet Design

CW/Eave Transition

AC Duct/ CW Transitions

How to back-estimate SHGC

GENERAL DESCRIPTION: The seminars focus on areas typically overlooked by architects and engineers in process of building envelope design. The topics are chosen on basis of observations derived from both forensic investigations of failed assemblies and peer reviews of architectural documentation.

Version.  This DVD has not been produced yet. Email us so we can gauge the interest.

Packaging:  May vary. We will probably switch to cardboard sleeves soon.

How Can I get it? We  sell them directly via the form below, as well as they will be available through third-party re-sellers soon.

Price: TBD. We also encourage a purchase of several DVDs at a discount.

fenestration DVD


Leave a Comment

Give Them the Second Life – A Call for Glass Samples

glass samples


Are you planning to dispose of architectural glass samples? The ridiculously heavy, 1 foot by 1 foot squares from the long-forgotten projects, which still take up the precious space in your office? Rather than sending them to a landfill, give them to us.

I grew up in a small communist country behind the iron curtain, and I still remember  a huge drum where all broken glass was duly collected in the corner of our local glazier’s shop for recycling.  I have not found such a drum in America yet.  When I had my window replaced, I learned that i’s nearly impossible to recycle window glass.  All the energy and resources embedded in these samples just end up in waste fields.  Architectural glass is seldom recycled. 

We need over 100 glass samples for an adaptive reuse project, where we will use them to glaze a brand new house. If you are in the South Florida area and have more than 50 of them, we can come and pick them up. Also, if you are further north and have sufficiently large quantity, reach out to us, we may be able to pick them up. Your name will be placed on the list of  donors displayed prominently on site.

Obviously, since I am an architectural glass freak, I prefer interesting glass samples, so I can play with them in my spare time… However, I know these samples you would rather keep for yourself anyway.  We prefer insulated AND laminated glass samples, as well as triple insulated samples, but ANY glass samples, as long as they are 1 foot by 1 foot size are OK.

Now, if you plan to follow our example, here are the details of the project: it’s a house of 100 windows, where glass samples are set directly in masonry openings to create a large scale mosaic effect. We will follow with photographs.

Thanks for your help!

I would like to thank the following firms: Arquitectonica, McHarry Associates, and Fergusson Glasgow Schuster Soto, Inc. for their donations of glass samples!

Leave a Comment

Fenestration Symposium in Raleigh, NC

I will speak this Thursday 4/24/2014 at the BEC Fenestration Symposium in Raleigh, NC.

All those who plan to come, please read this article about fenestration. It’s my old article about Glass Coolness published in The Construction Specifier in April 2013. We will talk about this stuff!

See you there!


Literature pertinent to the topics:

IBC Chapter 24 Glass and Glazing
AAMA Structural Properties of Glass (ca 1984)
ASHRAE Handbook of Fundamentals – Chapter 15 – Fenestration
ASTM C1036 Quality
ASTM C1300 Strength
ASTM C1172 Laminated
ASTM C1376 Coatings
ASTM E773 and E994 IGU tightness
Technical Publications by Manufacturers: Pilkington, Viracon, Oldcastle, AGC, etc.
Warranties which come with architectural glass products.

Here are the links you requested, not necessarily relevant to fenestration:


More links are in the widget titled “Links” at the bottom right corner when you scroll the page down.

The website with the Polish windows of 0.1 U value (no endorsement in any way):

My Publications:

(I just realized that neither the new nor the old website offer the complete selection, as I haven’t really updated much for almost two years.) Here is one from my old website:, the new one sorted by tags: and the new one sorted by categories:

More reading related to glass (warning – marketing content):

Some related photos downloaded online;



Leave a Comment

DIY- Reglazing with Polycarbonate

Single hung aluminum window reglazed with polycarbonate glass

Over one year ago I purchased a dilapidated house in Miami. Among many items that required repair, were broken windows. Seeing neighborhood kids throwing rocks at my windows, I realized that the ordinary glass wouldn’t do. I paid extra and reglazed them with polycarbonate glass. It’s something that I recommend to everyone: for approximately $100, you can make your window impact resistant by reglazing it with polycarbonate glass, and supplementing perimeter fastening. It won’t meet the official criteria of opening protection, but it would be in many respects better than a brand new, certified impact-resistant fenestration. For example: it won’t break when a kid throws a rock at it. (Read the rest of this entry…)

Leave a Comment

Movements And Tolerances In Curtain Wall And Cladding Design

Movements and Tolerances in Curtain Walls and Cladding

As difficult as it is to imagine, buildings move. Introduction of curtain walls gave the buildings even more freedom to move. The peaceful rigidity of bulky bearing walls and relatively short spans of oversized structural members belong to the past. Today’s buildings move a lot more.

In fact, the biggest single difference between curtain walls and windows punched in the load-bearing walls lies in the mechanisms that have to be implemented in curtain walls to accommodate the movements between both a cladding and a main building structure and among the cladding components themselves.

The movements are induced by same live load as in the past: users, wind, seismic, temperature and moisture fluctuations, with possible exception for mechanically (HVAC, elevators, etc) induced pressure differentials. The components of a modern building respond differently for several reasons. The material usage became more economical, yielding higher deflections; a thermal insulation isolated cladding from a body of the building yielding higher temperature differentials, the materials (metals and plastics) became more volatile themselves.

 Please fill the form below to receive this free PDF (It contains 21 figures, and 10 pages,  size 1.7 MB).

If you experience difficulties downloading this publication from here, you may try our old website download link.

[email-download download_id=”3″ contact_form_id=”501″]

Update: Thank you for your kind feedback. There are some texts  (I.e. the discussion of Spearin doctrine) which seem to be favorite among our dear readers. This article seems to be liked by architects to the degree I heard it was used as a textbook in architectural college. You can help other readers by adding comments and recommending the best ones. It’s awkward for me to make this determination.

Leave a Comment

In Support of Glazed Curtain Walls

In Support of Glazed Curtain Walls

Curtain wall supports are important to understand because they have a large impact on crucial architectural dimensions and perimeter transitions. (Read the rest of this entry…)

Leave a Comment

Sloped Glazing Consulting

Sloped Glazing Leak

We specialize in the architectural glazing. Skylights and sloped glazing are the primary examples where the source of leak may be obvious; however, you still need an expert to identify the REASON of the leak and come up with a working remedial design….

(Read the rest of this entry…)

Leave a Comment

Curtain Wall Consulting – Design Phase

Measure Twice, Cut Once.

Measure Twice, Cut Once. The bespoke unitized curtain wall mullion intersection model built by Kaz for the UPenn Hospital project designed by Rafael Vinoly Architects.
The white extrusions were printed in 3D printer. The IGUs are the true low-E glass samples of the type chosen by the architect, courtessy of Guardian.

We established enviable reputation in curtain wall design and engineering. We analyze the architectural design against client’s performance objectives, and match with systems available on the markets. We also optimize an existing design or engineer a new system from a scratch if necessary to meet project requirements. (Read the rest of this entry…)

Leave a Comment

Winter Window Condensation

What did you first notice on this photograph? If you are a sad individual like me, you noticed the condensation on the glass, which obstructs the view of the yellow wings and the black belly of the tit outside. This photo shows two environments inhabited by the tropical bird one one side, and the winter bird staring at each other, separated by the architectural glazing. A small miracle caused by the human intervention in the nature, and on the engineering side by the mechanical system delivering heat and the building envelope containing the heat.  The glazed partition conducts heat well, which warms the bird on the exterior, but chills the bird on the interior at the same time. Water condenses on the cool interior surface of the glass, dehumidifying the air adjacent to the window. Such a condensation inside is one of the most common problems with building enclosures in a winter. It wouldn’t have happened if the window was specified correctly and verified by simulations or testing.

Leave a Comment

What is Glass (Glazing)?

deterioration of laminated type of glass in window in Miami, FL

Deterioration of laminated glass in windows of the Miccosukee Resort and Gaming in Miami.

Glass is one of the strongest material known to man, although few would probably guess it, because of the common perception of fragility and brittleness. It has a great compressive strength, and in a sufficiently small scale (think fiberglass) it has also tremendous tensile strength (~10 times more than the ordinary structural steel).

HOW TO MAKE GLASS. If you grab a handful of sand and melt it with your acetylene torch, you would get glass. The process is called vitrification. But it wouldn’t look very pretty: just a glob of shiny substance. But if you poured this melt onto something flat, such as a molten tin, you would get a pretty flat glass sheet, resembling a window glass pane. This float method is relatively new, and prior to 1950’s, glass was formed by blowing and rolling, which produced awkward distortions.

SODA-LIME. In architectural applications we typically use the sode-lime glass, which simply means soda and lime (and some other additives) were added to the sand, in order to make it easier on the manufacturer. There are endless other formulations of glass, allowing for its use in such demanding applications as windows of space shuttles and smartphone and tablet touchscreens.

INSULATED GLASS. The average window glass pane today is manufactured by the float method, and then fabricated into insulated glass units (IGU), which is simply doubling glass plies with a cavity in-between, in order to reduce heat loss. If you, like me, tried to fabricate one yourself, be wary: it’s very challenging to permanently eliminate moisture from the cavity; therefore condensation forms inside the cavity, preventing clear vision.

LAMINATED GLASS. Glass breaks easily because in the architectural scale, its tensile strength is 100 times smaller. Therefore, it’s easy to get hurt by shards of glass, or fall from height through a broken glass ballustrade, or get hit by a windborne projectile (think a bird hitting your windshield). This is why before we place glass on walls, we glue two sheets of glass together in a process called lamination. The laminated glass comes with many benefits, but is relatively short-living.

DURABILITY. Glass is very durable. Absent few deteriorating (water+alkali) factors, it can last forever. The oldest known window glass is 270 years old. However, you noted the challenge I mentioned above: the average IGU spacer leaks steadily, and therefore the condensation would creep inside after 10 to 20 years. Also, the laminate layer in the laminated glass typically lasts only 5 to 10 years, particularly in the hot-and-humid climate, where it’s used the most for opening protection against hurricane missiles.

LOW E. Sun can easily turn your car or building into a frying pan. Not if you shield it with a sheet of metal. The trick is to make the sheet thin enough to become (almost) invisible, and prevent its corrosion and abrasion. Therefore, the average insulated glass unit has a thin layer of noble metal (i.e silver) deposited on the face of the glass facing the air cavity. It reduces the radiation, and makes your life easier, if you happen to have a window seat.

TOUGHENED GLASS. Glass can be toughened like steel, doubling or quadrupling its strength. The additional benefit is the reduction of size of the glass shards, which makes it less injurious. There are some drawbacks: Heat strenghtening requires placing glass in a furnace; therefore, glass size is limited by the size of the furnace (the typical 7 x12 ft limit), glass cannot be cut or drilled afterwards, and the fully tempered (FT) glass may break spontaneously due to nickel sulfide inclusion.

GLAZING. Glazing for windows or curtain walls, is the process of installation of glass panes in frames and sashes. The noun is also used interchangeably with glass, and so used in some building codes.

GLASS HOUSES. Many are fascinated by the idea of glass houses, popularized in the beginning of the 20th century. Architects, such as Ludwig Mies Von Der Rohe, benefitting from expanded production size capabilities, introduced full-height, wide glazed expanses into the modern architecture. In the 21st century, we are still slowly getting there, by using the strength of the glass to support the building structure; therefore eliminating any remaining visual obstructions. Have you walked on a glass floor or glass staircase (i.e. in flagship Apple stores)? These are examples of glass used in structural capacity, introduced by facade engineers such as Dewhurst Macfarlane & Partners.

Leave a Comment

3D Static Structural Engineering Simulations

3D Static Structural Engineering Simulations are performed for verification of stresses in the material or assembly.

Below is an example of an exaggerated deflection of the curtain wall mullion receiving reaction from the roof above.
3 D static von Mises

Using 3D Thermal Modeling to Improve Performance Requirements by Mr. Karol Kazmierczak – JBED 2/2010


Leave a Comment

2-Dimensional Steady State Thermal Analysis

2-Dimensional Steady State Thermal Analysis is performed on simple assemblies to identify the thermal transmittance (U value) and assess the condensation risk.  What is the thermal transmittance? It’s composed of the three modes of heat transfer: thermal heat conductivity, thermal heat conductivity, and radiation thermal.   It’s often expressed as U values (for windows, curtain walls, skylights, and other glazing).

2-Dimensional Steady State Thermal Analysis

These NFRC-compliant simulations are nationally accepted as an alternative of the expensive laboratory testing of fenestration. Also, this type of analysis can yield SHGC of the fenestration (measure of solar direct gain in windows) , with the popular software we use.


Leave a Comment

Daylight and Illumination Studies

Would it be too dark in the working spaces? Would prison guards be blinded by glare from windows precisely when inmates are out?

We never loose the primary function of glazing from sight: letting the natural light in.We perform daylight simulations and illumination studies to verify the daylight factor. Particularly useful in verification of compliance with the LEED credit 8.1 requirement.

Sample daylight studies.

Make your green building more sustainable! Optimize use of natural day-lighting to increase comfort, and minimize artificial lighting!

Leave a Comment

Spectrophotometric Simulations

Glass is seldom matched properly, as seen on the photos below, and therefore owners often require a blanket glass replacement, after only few pieces have been broken or scratched.

Glass is seldom matched properly, as seen on the photo

Save hundreds of thousands of dollars which would otherwise be spent on replacement of the intact old glass not matching the new replacement glass. (Read the rest of this entry…)

Leave a Comment

Seminar “Façade Engineering With Glass”

Façade Engineering With Glass How to use the glass to achieve the desired architectural goals, and what advances in technology help to shape the modern architecture

Glass is the design medium of the today’s architecture and it will may easily become the material of choice of tomorrow. Kaz developed a new seminar about the architectural glass, which addresses the typical architectural questions: how to use the glass to achieve the desired architectural goals, and what advances in technology help to shape the modern architecture.

(Read the rest of this entry…)

Leave a Comment

Sloped Glazing – Problems and Solutions

This is the BEST3 Conference paper. The DVD will follow soon. Its working title is  “Skylight 101, or what you have always wanted to learn about sloped glazing.” It presents typical challenges and solutions associated with sloped glazing and skylights, (Read the rest of this entry…)

Leave a Comment

Glass Coolness – Additional Clarification

This is a follow-up to the post titled “Glass Collness.”

In response to my critique of the FBC  insulated glass requirement in the South Florida, we received a question from an architect, who wrote: “Surely you would not claim that double glazing with a low-e coating on the #2 surface would cause more energy use in the building than single glazing, would you?” (Read the rest of this entry…)

Comments (2)

Glass Coolness

Windows are as old as buildings, the word itself derived from the ancient Norse language in times when Vikings raided North Europe. How to design a window? How should an architectural glass be chosen?  Vikings are long gone, and we found the knowledge remains common among architects in the North Europe, but has not spread much ever since, judging by some familiar examples. Nowhere else so much could be wasted by so few: the glazing is the most advanced and the most expensive part of many facades; therefore, it warrants a good, more than a skin-deep design.

In this article, titled “When You Need a Window – Solar Design” Kaz attempts to shed some light on two elementary aspects of glass engineering: visible light and solar transmittance. Their combination is called  the coolness factor and happens to be the the most important solar glass benchmark and part of the historical quest to bring the natural light deeper into the buildings while avoiding perimeter discomfort.

The link allows to download and open selected articles free of charge. However, we need you to leave us your email address in order to download them. Your contact info is safe with us, according to our privacy policy .

General Comment from Kaz: Dear Readers, Thank you for your emails and comments typed in the download form. These are very valuable and I appreciate them, and will answer every question, as the time permits. However, the purpose of this blog is the education of the general public. Therefore, I would appreciate if you could  kindly post your questions publicly, clicking on “Leave a Comment” above. This way both questions and answers will benefit everyone. Please, also keep in mind that unless you contracted our consulting services, we reserve the right to post your questions and our answers publicly anyway because the purpose of this blog is the education of the general public.

07/18/2011. Additional Clarification by Kaz is posted Here.


In April 2013, my article was printed by The Constuction Specifier under the title “Solar Design for Windows” and is available free of charge here.



Comments (1)