Feedback about the value of LBNL windows software tools

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D. Charlie Curcija/LBNL

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Jul 11, 2024, 4:42:30 PM7/11/24
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Dear WINDOW and THERM users, 

We are looking for your feedback about the value of LBNL windows software tools. How do they help you in your everyday work/practice? Any interesting outcomes from using our tools that you would like to share? Also, please let us know how your work would be affected if our windows software tools were no longer developed and maintained?

We greatly appreciate if you can share your experience and feedback

archi...@gmail.com

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Aug 2, 2024, 9:57:48 AM8/2/24
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Hello Charlie,

I can say that for me THERM is an unparalleled software for educational and professional uses.
I personally use it almost daily in my work as an architect specializing in energy-efficient building envelopes, and the possibility that its development could be discontinued would be dramatic news in my opinion.
By the way, this is an excellent opportunity to thank all the developers of the THERM and WINDOW software.

Ciao
Fabrizio

Chieh Chih Chiang

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Aug 2, 2024, 10:59:11 AM8/2/24
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LBNL software is absolutely critical to our work. Granted, it can be a painful process at times (Antiquated UI, difficulty integrating into automation workflows, lack of built-in alignments to standards outside North America) but without LBNL, we'd have to turn to commercial products for thermal analysis. Hope you're not thinking of discontinuing LBNL software!

Robin Mitchell

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Aug 2, 2024, 2:34:12 PM8/2/24
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Fabrizio

Thank you for your comments about your use of THERM, which we will pass along to our U.S. Department of Energy funders !

And thank you once again for all the great support that you lend to other THERM users on this forum. Your knowledge about how THERM is used far exceeds ours and it is wonderful that you, and others, take the time to help your fellow THERM users. 

Have a great weekend !

Robin 

Robin Mitchell

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Aug 2, 2024, 2:37:39 PM8/2/24
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@cchiang -- Thank you for your comment about THERM. 

We are hoping that comments such as yours, about the importance of the software to your work, will allow our software team to continue to receive funding from the U.S. Department of Energy, to develop THERM, even with it's antiquated interface : <. which we are very much aware of !!

Robin

Dan Bettenhausen

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Aug 2, 2024, 3:29:31 PM8/2/24
to Robin Mitchell, THERM
Robin,

I drafted a letter on behalf of Enclos. It is attached. These products have been a great benefit to us over the years.

Dan

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Dan Bettenhausen
(612) 819-9674



THERM and WINDOW Memo for LBNL.pdf

Robin Mitchell

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Aug 2, 2024, 6:00:25 PM8/2/24
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Dan

Thank you so much for your letter of support. We will provide it to our U.S. Department of Energy funders. 

Robin

David Collins

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Aug 2, 2024, 7:37:52 PM8/2/24
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I like the interface.  It makes me nostalgic for the 90's.

Warm Regards,

- David Collins

Robin Mitchell

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Aug 2, 2024, 7:53:59 PM8/2/24
to David Collins, THERM
Ha!!🙃

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Reichard, Georg

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Aug 3, 2024, 9:07:04 AM8/3/24
to Robin Mitchell, THERM

I can easily provide a letter from Virginia Tech, speaking for the construction side.

 

But I’d also be happy to bring this up with the SBSE board if they’d be willing to support a letter or petition, which may speak for more schools and across the A/E/C domains to support the project in DOE/LBNL.

 

Best,

Georg

Robin Mitchell

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Aug 3, 2024, 4:11:59 PM8/3/24
to Reichard, Georg, THERM
Georg

It would actually be great if you could do both !!

Thank you so much !

Robin
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Robin Mitchell
Building Technology and Urban Systems Division
Energy Technologies Area
Lawrence Berkeley National Laboratory

WARM Low Energy Building

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Aug 14, 2024, 12:50:36 PM8/14/24
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We have used THERM extensively in the past for the calculation of Psi-values for building details. Whilst we generally use a commercial package now for in-house calculations, we offer a course in how to use THERM for this purpose:
There is at least one other company in the UK offering a similar course to ours. All of them cater to professionals who value the insights the software gives them in achieving low energy junction details and in highlighting the potential for condensation based on the fRsi.

It would be a great shame if the team who maintain the software were to lose their funding.

Best wishes and thank you to LBNL!

Liam McDonagh-Greaves
WARM: Low Energy Building Practice and Coaction Training.

Robin Mitchell

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Aug 14, 2024, 12:58:22 PM8/14/24
to WARM Low Energy Building, THERM
Thank you very much for your support of our software!

Robin

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Rebecca Powles

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Aug 15, 2024, 11:51:35 AM8/15/24
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Hi Charlie,
LBNL tools are an integral part of the Australian building physics and energy performance landscape.  They are seen as the gold standard for the up to date and scientifically credible evaluation of the thermal and optical performance of building materials in research and industry practice.  They are integral to the Australian energy rating programs for windows, doors and window coverings, and it would be extremely challenging to replace them in those roles if they were no longer developed.  
Best regards,
Rebecca

----------
I am also passing on this message and attached magazine article from Nayan Das who is not a member of this group:

 --------

LBNL software tools such as THERM and WINDOW play a vital role in evaluating the energy performance of glazing systems and engineering appropriate glazing solutions. These approved tools under Australia’s WERS rating scheme ensure that designs meet energy rating requirements under the National Construction Code. This highlights the significant role these tools play not only in the glazing industry but also in the broader building sector. For instance, THERM's capability to model thermal bridging impacts is highly valued by architects and other building professionals.

 

Attached is an article from a magazine that further demonstrates the application of such thermal models. In this instance, the model shows the impact of concrete slab edge insulation.

 

Thank you for the continued development and maintenance of these valuable tools.

 

Hope this is useful.

 

Kind regards,

 

Nayan Das

Product Engineering Manager


 

Dowell Windows Pty Ltd  

312 Woodpark Road, Smithfield NSW 2164

W dowell.com.au


Magazine Artcile.jfif

WARM Low Energy Building

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Aug 16, 2024, 5:37:20 AM8/16/24
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Hi Charlie and Robin,

We would be keen to post about this on LinkedIn, with a link to this forum page. It would probably generate a lot of traffic and resulting statements of support. However, I notice LBNL have not already posted about it on LinkedIn and wanted to ask if there is some reason for this. If we post on LinkedIn, is there anything we need to be aware of/not mention, politically? We are keen to help out!

Kind regards,

Liam McDonagh-Greaves
WARM: Low Energy Building Practice

Speckel

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Aug 18, 2024, 7:01:33 PM8/18/24
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All,

Therm is also critical to my work as a building physics consultant and has been for over 15 years.

I am not alone.

Students and professionals alike use Therm as a backbone to their understanding of building physics in design and application.

If the team at LBNL need further support, I and many in this forum would happily provide it to ensure development and maintenance is maintained. 

Thanks

Darren

On Friday 12 July 2024 at 06:42:30 UTC+10 D. Charlie Curcija/LBNL wrote:

k.ros...@gmail.com

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Aug 19, 2024, 3:52:31 AM8/19/24
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It's an invaluable software that I and my students regularly use for research and education. If THERM was no longer available/maintained, teaching about thermal bridges, and reducing thermal bridges in construction would require buying expensive licences of similar proprietary software. I would need to change my teaching practices entirely.

Paul Caicedo

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Aug 19, 2024, 11:27:08 AM8/19/24
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THERM is a great tool that we use intermittently at a commercial level. The main use for us is linear thermal bridging for specific details. It is a perfect fit because there could be a couple of months where we don't complete this type of analysis, but it also happens that we use it heavily for a few weeks. We were excited to know that the hygrothermal calculation is in process, understanding the limitations of the engine at the moment, but hoping that it could be used like WUFI at some point. After many years of development, it would be very sad to see the cancellation of the funding. There could be some scenarios like making it free for academic and research purposes, offering competitive prices for commercial use (compared to Flixo, etc.), providing perpetual licenses for major versions,  monthly subscriptions, etc. These are just some ideas to sustain the development of the tool.  

Steve Zhou

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Aug 19, 2024, 10:21:53 PM8/19/24
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Dear THERM software developers, LBNL staff and DOE officials,

I have been using THERM software for two decades and have also tried the other thermal simulation tools for some time. From my point of view, OPTICS, WINDOW and THERM (short for "THERM") are the greatest thermal simulation software ever.

Since the oil shortages of the 1970s, people have been actively discussing the future of the planet and looking for sustainable solutions. Later, it was recognized that the building envelope, which separates the unconditioned outdoor environment from the conditioned indoor environment, is one of the most important factors affecting a building's energy use and carbon emissions. Soon, countries were establishing their own regulations to ensure energy efficient buildings.

The design requirements usually specify limits for U-value, Solar Heat Gain Coefficient (SHGC), and Light Transmittance (LT). It is the daily work of designers and engineers to work together to make sure these requirements are met for the project. Sometimes they have to fight for that second or even third decimal in these parameters to prove that their design is energy efficient so that it can be approved for construction.

The mission is impossible without THERM because the entire building industry, including material manufacturers, architects and engineers, fabricators and contractors, have been using THERM for three decades. There are other commercially available simulation tools, however, THERM is believed to have the largest number of users worldwide. This confidence has been built because THERM's features, knowledge base, technical support, and commitment to developing and improving are second to none.

According to the roadmaps of the countries that signed the Paris Agreement, reducing U-value is the way to go. Taking fenestration as an example, we know that Stage #1: reducing U-value (IP unit) from 1.2 to 0.6 was easy; Stage #2: reducing U-value to 0.3 takes some effort; Stage #3: further reducing U-value to 0.15 will be challenging. At the moment, most of us are at stage #2. THERM has done a very good job so far, but needs to do even better as we move towards Stage #3. Continued development and improvement of the THERM software is key to our success in reducing carbon emissions.

Last but not least, I would like to take this opportunity to thank Dr. Charlie Curcija, Robin Mitchell for hosting the forum, and the enthusiastic contributors from whom I always learn something.

All the best,

Steve

Claire Wu

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Aug 20, 2024, 2:11:59 AM8/20/24
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Hi Dr  Curcija and LBNL staff,
It's integral to our day-to-day work here in Australia, and it is a huge part of our facade industry. There is a lot of feedback that I can provide to make the user experience better, but it sounds like that would be for a separate post. 

Luca Caruso

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Aug 20, 2024, 12:54:20 PM8/20/24
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Dear LBNL THERM Team,

I am sharing with you one of my recent peer-reviewed papers, showing the importance of software like Therm for complex 2d FEM simulations.


The Double C Block Project: Thermal Performance of an Innovative Concrete Masonry Unit with Embedded Insulation
Abstract
The Double C Block (DCB) is an innovative composite Concrete Masonry Unit (CMU) developed to offer enhanced thermal performance over standard hollow core blocks (HCBs). The DCB features an original design consisting of a polyurethane (PUR) foam inserted between two concrete c-shaped layers, thus acting as the insulating layer and the binding agent of the two concrete elements simultaneously. The purpose of this research is to describe the results obtained when assessing the thermal transmittance (UDCB and UHCB) of these blocks using three different methodologies: theoretical steady-state U-value calculations, numerical simulation using a Finite Element Method (FEM), and in situ monitoring of the U-value by means of the Heat Flow method (HFM). The results obtained show that the three methodologies corroborated each other within their inherent limitations. The DCB showed a performance gap of 52.1% between the predicted FEM simulation (UDCB was 0.71 W/(m2K)) and the values measured via HFM, which converged at 1.47 W/(m2K). Similarly, a gap of 19.9% was observed when assessing the HCB. The theoretical value via FEM of UHCB was 1.93 W/(m2K) and the measured one converged at 2.41 W/(m2K). Notwithstanding this, the DCB showed superior thermal performance over the traditional block thanks to a lower U-value, and it complies with the Maltese building energy code. Further improvements are envisaged.

And I am looking forward to testing the version 8 ready for dynamic hygrothermal FEM.

Regards

LC

Robin Mitchell

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Aug 20, 2024, 12:57:29 PM8/20/24
to Claire Wu, THERM
Claire

We are always interested in hearing feedback about how to improve the program, although our resources are limited. But I do keep a giant list of issues we would like to address in our software. 

Feel free to start another thread about this, that others could also chime in on !

Robin

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Robin Mitchell

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Aug 20, 2024, 12:58:59 PM8/20/24
to Luca Caruso, THERM
Thank you to everyone who has shared how they use THERM and WINDOW. It is incredibly valuable to get this information and we are compiling it to present to our program managers at the US Department of Energy. 

Thanks again !

Robin 

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Elliot Glassman

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Aug 20, 2024, 1:27:28 PM8/20/24
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Hi,

I have used THERM a lot but seldomly in the native environment.

On many projects I have used the Ladybug Tool's component developed by Chris Mackey to connect Grasshopper for Rhino to THERM. This not only makes drafting much easier than native THERM, but has allow me to parametrize the details... I can iterate on assemblies much quicker than the conventional workflows. See an example here: https://youtu.be/ttTotnox2FY

A great outcome of this process on one project was we were able to iterate enough to find a solution on a project that not only performed better but cost less to build. Not sure if we would have identified that solution if we hadn't been able to iterate as much.

This component only works on Rhino 6 and THERM 7.6.1 I believe, so it has not been updated for a while. Happy to dust off my older versions to do this process, but it would be great if that LBNL and Ladybug tools partnership that created this first version could be updated to the latest versions occasionally as it has proved very useful.  

Gina Windley, Architecta

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Aug 23, 2024, 2:54:26 PM8/23/24
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Hi,

I am writing to express my strong support for the continued funding of the THERM software. As an architect who specialises in sustainable design, THERM is an invaluable tool that allows us as designers to assess and optimise building performance at an early stage in the process. It provides crucial insights into thermal bridging, enabling us to make informed decisions on our retrofit projects. Its accessibility as a free tool has made it possible for small practices like ours to engage with these essential calculations without the financial barrier of costly software packages.

The potential loss of funding for THERM is deeply concerning. Without it, like us many in the industry would lose a vital resource that contributes to the creation of healthier, more energy-efficient buildings. I urge the continuation of support for THERM and its development!

Best regards,

Gina Windley
Architect and Co-Founder, Architecta

Robin Mitchell

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Aug 23, 2024, 2:56:54 PM8/23/24
to Gina Windley, Architecta, THERM
Thank you Gina !

Robin

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Thomas Lodge

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Aug 29, 2024, 12:36:08 PM8/29/24
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I'd like to express my support and gratitude to the LBNL software, especially THERM creators. It has been crucial in my work to promote and explain thermal bridges to commercial clients and other colleagues. Without this free software, I would struggle to have the evidence to back up the detailed changes needed to ensure thermal bridge-free designs paramount to low energy and efficient buildings. THERM has been crucial in applying thermal bridge-free design to all clients without costing the business or client. Without funding to keep this software free, we will struggle to maintain this work.

Collin Robinson

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Aug 29, 2024, 11:12:11 PM8/29/24
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I use THERM and WINDOW primarily, in an architect and sustainability consultant role. I occasionally use AERC, Optics, and COMFEN. They I am very grateful these tools and the relevant databases IGDB and CGDB are kept updated and robust. In my role it’s vital to produce independent thermal and visual assessments in the design phase without relying on manufacturers who may not be awarded the project in the end. LBNL software is used and accepted universally in the technical building field, as I found repeatedly. Being able to speak that same language when the going gets tough has been vital. It’s a matter of patriotic pride that this kind of software is free and its results reliable. 

One of the most valuable ways of using the software has been testing ideas I’ve read about, or conventional wisdom on a subject. For example, I developed my understanding of low-e coatings’ dramatic impact by testing different scenarios in the software, probing the limits by iteration. Another example is being able to independently test window frame by drawing them in Therm, and with its error correction on frame sections get usable results on window assemblies. Having Window at my disposal is particularly vital in getting architects to pay attention to and work with assembly u-values, since they would prefer to just look at center-of-glass data. With Window (and free access to NFRC standards thanks) I can quickly show the assembly values while decisions are being made. 

Recently I was able to provide a new service looking at a particularly odd detail and evaluate condensation risk with reasonable confidence. Surprisingly, this task showed that a steel thermal break was less prone to condensation than anyone expected. I am very proud to be able to do this in-house at my architecture firm, quickly and inexpensively. That would not be possible without these software tools. Also vital is the robust BSDF functionality, when combined with layer data from manufacturers, and generated in the program. Doing annual daylight simulations with these custom XML files is relatively straightforward. This allows me to provide accurate results again backed up by the confidence LBNL tools command. 

Lastly, LBNL staff and other users respond to issues and continue to update functionality. If these software tools were no longer kept current, it would eventually have a very negative impact on my practice. That would a shame, right at a time when I feel like topics like thermal bridging and complex fenestration are growing in application among architects. 

Sincerely,
Collin Robinson
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