To find out what our users have been saying about DesignBuilder read on...

Paul Sentobe, Business Footprint Ltd: “I have been using DesignBuilder for non-domestic EPCs and compliance modelling since 2008. Having done many hundreds of models in DesignBuilder, I have been very pleased with the way the software has steadily evolved over the years. I briefly switched to using another UK Level 5 approved tool due to DesignBuilder not having approval for Level 5 DSM assessments at the time (it subsequently released L5 DSM in early 2017) but found it was more expensive and much more difficult to learn than DesignBuilder, and time-consuming to use; even after becoming relatively experienced using it. Switching back to DesignBuilder was therefore an easy choice. With the MEES legislation driving greater volumes of Level 5 DSM and simulation work, it is fantastic to be able to quickly and easily switch between SBEM and DSM modes in the same model to determine which gives the best rating for the MEES client (mostly DSM, but not always!). The service provided by the admin and technical support teams at DesignBuilder has also been first-class, with helpful staff responding quickly. I would thoroughly recommend DesignBuilder, particularly for UK Level 4 SBEM assessors wishing to ‘upgrade’ to Level 5 for DSM and MEES assessments which is a very straightforward process. Thanks to all at DesignBuilder, keep up the good work!"

Joe Davies BSc(Hons), JD Energy: “In my previous role as a technical consultant for the UK’s largest accreditation scheme, I had the privilege of using and regularly QA-checking models from all of the approved non-domestic EPC software tools. It is no coincidence that having left that role I have now chosen to use DesignBuilder for my own EPC, Part L and MEES work. I have always found DesignBuilder to be intuitive and easy to use, allowing the rapid and concise input any building from simple two zone shops to the large, complex and fiddly multi story monsters. I am far more productive than if I had stuck with iSBEM, there is no doubt that DesignBuilder is cost effective and it only takes a few EPCs to pay for itself. DesignBuilder’s SBEM and DSM training was blissfully straightforward and very good value, once I started using the software I very quickly picked up the finer points with assistance from the excellent free online video tutorials. If you aren’t fully satisfied with your existing software, I would have no hesitation in recommending DesignBuilder. "

Tejes Das: “DesignBuilder have just delivered two days of first-class bespoke simulation training for me. The training was based on my own priorities to help improve my knowledge in specific and more advanced modelling areas, and has undoubtedly fast-tracked me to become a more advanced user of the software. I would have no hesitation in recommending this form of training for those who are already using the software but who want to progress more quickly on advanced topics such as Parametric Analysis, Optimisation & EMS. Thanks to the DesignBuilder trainers and admin team for making this such a great experience!"

Prof. Malcolm Cook, Loughborough University, UK: “At a time when we are all busier than we would like to be, it is refreshing to do business with a company in tune with the needs and limitations of the academic sector. The level of customer service we have received from DesignBuilder during the testing, purchase and installation of the software has been exemplary and pain-free. Thank you."

Russell Pridgeon CEng LCEA MCIBSE MIET, Enquire Consulting: “I have used DesignBuilder for a number of years and regularly train Level 3 and 4 Energy Assessors for one of the leading NDEA training organisations. We transitioned to DesignBuilder for the training around a year ago, having used iSBEM for a number of years, and have had remarkably good results.

DesignBuilder’s intuitive interface has made it much easier for the trainees to pick up the software aspects of the training and that has enabled us to reduce the time we need to spend on software instruction by around a half. Even students with limited IT skills have been able to pick up DesignBuilder SBEM much more quickly than iSBEM due to DesignBuilder’s data management tools and the graphical interface that helps them to visualise their work much more easily.

We have seen a significant improvement in the quality of the work produced by the delegates, and we now have increased confidence in their competence to produce EPCs and BRUKL reports. There is clear evidence of this in the improvement in exam results since switching to DesignBuilder.

We would encourage anyone working in the Energy Assessment and Building Modelling areas to look seriously at how DesignBuilder can improve their results and save their time!"

Dave Bryan AIA, LEED AP, Third Level Design, Minneapolis
"I have used DesignBuilder for a number of years because I believe it is the best software package available for designing high performance buildings. It is easy to set up a model in early design. The model provides both an estimate of energy consumption and a 3-D visualization of the project that can be shared with clients. The same model can be continuously updated with more detail as the project evolves. <br
I recently attended the DesignBuilder training in Denver which reinforced just how quick to learn and easy to use DesignBuilder is compared to the other similar tools I’ve tried. I would be happy to recommend DesignBuilder software (and their training) as a way of helping modelers produce accurate results and outputs for loads/sizing and energy analysis. With the ability to also undertake daylighting and CFD analysis from the same model you use for loads and thermal simulations it seems DesignBuilder have all the capabilities most architectural and engineering firms would need in one efficient package. "

David Ellis PE, Virginia 22102, USA:
"I have watched the steady progression of DesignBuilder for the last 10 years or so, and having seen recent improvements in DesignBuilder’s HVAC and LEED modeling I decided to attend their training. I was both surprised and pleased to find how easy to use DesignBuilder is compared to the other similar tools I’ve tried, especially given the power and flexibility offered by the underlying EnergyPlus, Radiance and CFD engines. I’m really pleased that after a week’s training I feel ready to produce accurate results and outputs for loads and sizing calculations and energy analysis. The ability to also undertake fully-integrated daylighting and CFD analysis from the same model you use for loads and thermal simulations is also a very big plus point."

Dr Shahaboddin Resalati - Senior Lecturer in Sustainable Architecture and Building Physics Architectural Engineering Group, School of Architecture, Oxford Brookes University, UK:
"We have had a very positive experience with DesignBuilder this semester as it was the first year we shifted from our previous simulation software to DesignBuilder. Our students seem to spend less time on learning the software and more on actually understanding the results and being able to analyse them."

Alessandro Righi, architect and researcher at IUAV - Laboratory technical physics:
"The graphical user interface of DesignBuilder is comprehensive and intuitive, allowing us to model complex buildings simply and quickly. The data management structure (data hierarchy and inheritance) allows us to assign model data quickly and accurately, improving our efficiency. The power and flexibility of EnergyPlus, the underlying simulation engine, enables us to model a building in fine detail where required so that we can accurately analyse its performance. This is particularly helpful when calibrating the model with actual energy consumption to obtain a reliable close match when assessing potential improvements and energy conservation measures."

Iain Begg, Senior HVAC Engineer, Shell Projects and Technology Group, Aberdeen, Scotland:
"We utilised DesignBuilder software to carry out detailed natural ventilation assessments on buildings at our UK gas plants in order to demonstrate compliance with hazardous area regulations. First of all I would like to praise the initial support received from DesignBuilder staff, who were extremely knowledgeable and provided a welcoming point of contact for support and advice. Having used the majority of the alternative building simulation software packages on the market, I found without a doubt DesignBuilder the most user friendly and enjoyable to use. The modelling program itself is fantastically simple allowing even complex buildings to be developed quickly and easily. The user interface of the calculation part of the software is well thought out and the results outputs are graphical and concise. Within a few hours I had got to grips with the software and obtained the results I desired. It has allowed Shell to present compliance to regulating authorities, who were also impressed with the visualisation displays and graphical outputs. I fully endorse DesignBuilder, and in particular how easy it was to learn and use compared to similar building simulation software on the market. "

Professor Ljubomir Jankovic, Birmingham School of Architecture, Birmingham City University
: “DesignBuilder’s clear, well-structured layout and intuitive help system makes it a much simpler tool to learn and use, and compared to other simulation packages the creation of professional-looking geometry is much easier. The ease of use extends to other areas of the program such as thermal bridging analysis and setting up HVAC systems, and the capability to easily model adjacent ground conditions is very useful. A very important aspect of our work is optimisation, and DesignBuilder seems to be the only software that currently provides this functionality. We are encouraged that the development team have taken some of our functionality and user efficiency suggestions on board for the next release. We are already using DesignBuilder for research, and for the above reasons we think it is a tool that our students will find easier to use so we will be using it for teaching next academic year.” 


Warren Gray, Mechanical Engineer, Solid Green Consulting: "We decided to go out and measure some natural light levels in buildings that we have access to.... One building was our own office, and the other was a green building we worked on which will be tenanted in 2 weeks so we had a chance to take readings in the same environment for which we simulated. I am happy to say that the DesignBuilder results are very close to what we measured... What impresses me is that if we measure a value of 250 lux at 3m from the facade, DB returns similar values. This means that if we say that 40% of a building's usable area will have lux levels of 250 or above, then the measured results correlate with that. ... It certainly makes us confident in the results we give to clients."

Dr Manfred J. Zapka, University of Hawaii:
"First of all I would like to thank you very much for the outstanding online training that you made possible for our team. I was very happy that we could join with three people in an online training that offered us as an outstanding value. ... The course with DesignBuilder is going very well and we have some great feedback from the students.... Your data entry GUI makes it easy for students not only to “accept defaults” but to experiment. In addition your online help is extremely thorough and you present not only the theoretical background but also offer great links to the reference. You might not realize what a powerful learning tool this is; but it is. We think you have created something very valuable and we are looking forward very much to where your company goes from here... Thanks again for your great support. "  

Mark O’Neill, DM Hall LLP,
Glasgow, Scotland: "Gold stars all round .... Many thanks again for the high quality of customer service I receive from all at DesignBuilder, it is quite refreshing and a credit to your company."

Dr. Alex Friess Associate Professor, Rochester Institute of Technology Dubai, UAE: "I have been using DesignBuilder in the context of my Sustainable Energy Management graduate course in Mechanical Engineering since 2009. The driving factors in choosing DesignBuilder were the software’s extensive capabilities and EnergyPlus engine, coupled with an easy to use interface. Students have been able to very quickly learn to use and apply it as an experimental tool to explore the adequacy of energy management measures. It has allowed the introduction of an experiential learning component into the course that is invaluable in providing insight into the building energy balance and the effectiveness of energetic measures. I am highly satisfied with DesignBuilders capabilities and interface, and with the support and service received. Thank you very much."

Dr. Farshad Nasrollahi, Assistant Professor, Berlin University of Technology, Germany
I used DesignBuilder for the first time during my doctoral studies at the Berlin University of Technology. Since it uses EnergyPlus as its simulation engine, it is a very accurate and powerful simulation software tool and at the same time has a very easy to use interface. DesignBuilder has extensive capabilities that cover most of the features building energy simulation users need. Therefore it is a fantastic simulation software tool for all building simulation user groups, especially for architects and architecture students. I was so satisfied with the capabilities of DesignBuilder as well as with the high quality of customer service during my doctoral studies that I am using the software for my postgraduate sustainable design and simulation course at the Institute of Architecture at the Berlin University of Technology. Another reason for choosing DesignBuilder for education is the easy and quick to learn teaching process. The experiences from my course show me that students were able to learn how to use and apply DesignBuilder very quickly for simulation and optimization of building energy performance.


Jean Marais, Big-Gruppe, Berlin: "I’ve just discovered how the shading from other buildings was written out with transmission schedules to the EnergyPlus idf of the building that I’m currently simulating. I love the way this whole thing hangs together and again just want to compliment you and your team on a cracking job. From a total design point of view, I absolutely love this program. I find it very well thought out and I enjoy using it."

Roy Redhead, RJR Independent Energy Assessors, UK:
“I was looking for a way to improve accuracy and speed up production and found that DesignBuilder is capable of helping me do both. Complex roof structures and multi zone properties can be created so quickly it eliminates tedious and seemingly endless hours on area calculations for individual zones. Not only can I get to the end result more quickly but it makes running the recommendations back through the model simple and the information to the client much more valuable. No need for a calculator now, simplify adding offices to Portal frame buildings, saw tooth roofing with complex angles are so easy. Using templates of the types of building visited regularly in my area means I can enter entire project data sets in a single click”. 

Michael Reilly, Director of Operations, CADmeleon, Scotland:
  “…I looked at [another supplier] first as I had used this throughout my further education … however I was not entirely satisfied with the customer service that this company provided, it seemed every time you called in with a problem with the software… a cost was incurred, and a staffbase who take every opportunity to query the purchaser of their software’s intent. I then looked at DesignBuilder along with a few other software solutions to the iSBEM problem, DesignBuilder became the software of choice for CADmeleon, this also meant that the other company’s that we work with on large scale projects (Green Energy Partners and Dearle & Henderson) followed suit and chose DesignBuilder as our sole software for level 3 & 4 Buildings. By using DesignBuilder I estimate that our establishments can process certificates up to 3 times as fast compared to the iSBEM method, this has allowed us to excel in the Scottish market, enabling us to become well established as a major player in Energy Performance Certificates in Scotland. I have even held masterclasses with some of our clients showing them how to manipulate the data held in their models to improve their ratings which has involved them buying seats of DesignBuilder, East Ayrshire Council being one. I am also regularly tasked with travelling to the USA where our parent company operate, to assist them in working with clients requiring Technical Energy Analysis’ which will involve the EnergyPlus package. I hope to secure contracts within Michigan this month for over 200 buildings. Hope this explains why I am so happy with DesignBuilder.”

Miguel Bolivar, MSc Graduate, Southampton University, UK
: "DesignBuilder not only helped me to validate my results but allowed me to get in touch with an advanced building energy simulation tool and test some of its capabilities. As a mechanical engineer, the 3D interface when developing the graphics models is really easy to use and when setting materials, activities and HVAC properties the libraries and information available is really useful under a very user-friendly environment. The simulation speed is short which made easier the iteration process."

Paul James, Director eCubed Building Workshop, NZ:
"Just thought I'd drop you a line, I've been working with teams using modelling software for a number of years, and I would like to say how impressed I am with the responses and the development being achieved with design builder. The product is being developed with the design process in mind and this is fantastic from my perspective. Keep up the good work..."

Miguel Pelicano, MANVIA - MotaEngil group, Portugal:
"I am responsable for building the geometric model, simulate and determine the energy class of almost 100 supermarket stores from a big portuguese company. DesignBuilder is my "army knife", really a must! A great software from a great team! Thank you, great job! "

Stephen Dunn, Director, SDS Energy, UK
: "SDS Energy based in Northern Ireland have been using thermal simulation software for the last three years to demonstrate building compliance with Part F of the Northern Ireland Building Regulations, using SBEM and carrying out overheating calculations for new build projects. After assessing all the software tools available we adopted DesignBuilder in March 2008. Since then we have found the time required to produce EPC and carry out Building Regulation compliance checks has been much reduced boosting our productivity and profits. DesignBuilder has met all our requirements and expectations:

  • Cost of training, license and technical support are very competitive.
  • The software is intuitive and very easy to learn.
  • Speed - the software gets to grips with simple and complex models quickly. The software is easy to navigate especially when making changes to base models thus providing a fast response time to clients or Building Control departments
  • Technical support – it is vital that you have access to capable technical support by email or telephone and we have found this with DesignBuilder; you have a direct relationship with a dedicated software engineer who understands your business.
  • Visualisation – the building models can be displayed on screen and this helps the clients understanding of his building. Design changes and tweaks can be easily assessed visually in front of the client with great speed; we find this beneficial with hands on clients and architects.
  • Reliability – DesignBuilder has proved to be very stable and reliable, other software we had used in the past had a tendency to crash. "

Mark Buckley, MBA Engineers, Ireland: "Many thanks for all the help online, over the phone and in person. The software is very user friendly and is backed up by a great team who go out of their way to assist in any way they can."


Justyna Latarska, Masters Student, Warsaw University of Technology, Poland: I used DesignBuilder for my MA thesis. The purpose of the work was to carry out yearly energy simulations for several variants of an office building. DesignBuilder allowed me to clearly understand the impact of the details various parameters on energy use in the buildings under analysis. The program has a very accessible interface and many useful functions. Thanks to its intuitive design the program is useful not only for engineers or architects but also for students. A large library of materials, schedules and systems helped me to create the simulation models. A great advantage is the number of simulation results available, which enable efficient and multivariate performance of various energy analyzes.