Calculate Heat Loss to the Ground with Marc Rosenbaum

Marc Rosenbaum, Director of Engineering, South Mountain Company and one of HeatSpring’s expert instructors, taught a free live lecture to more than 200 architects and builders last week. His focus: demonstrate how buildings interact thermally with the ground and teach people how to calculate heat loss to the ground.

Access Full Lecture and Additional Resources Here

During the live lecture, Marc started with a 2D THERM model of a basement, reviewed the U factor that THERM calculates for the foundation assembly, and used that to calculate the design heat loss of the basement. He showed the attendees how to estimate the annual heat loss as well.


He then presented the simplified Los Alamos algorithms for calculating heat loss from basements and slab-on-grade foundations and used those to analyze the model and compare the result with the THERM calculation.


At the conclusion of the lecture, Marc discussed how to apply the algorithms to a walk-out basement condition and how to estimate design heat loss in the case where the insulation is in the frame floor over a basement.

Learning Takeaways

  • Learn about relative conductivity and heat capacity of soils vs. air
  • Learn about variations in soil temperature with time and depth
  • See the results of a 2D THERM model of a basement, including the temperature distribution, direction of heat flow, and heat loss rates
  • Learn about using the U factor calculated by THERM to estimate foundation heat loss
  • Learn how to do simplified heat loss calculations for basements, slab-on-grade, and walkout basement foundations
  • Learn how to estimate design heat loss through an insulated floor to a basement below

Marc Rosenbaum is the Director of Engineering, South Mountain Company. He uses an integrated systems design approach to help people create buildings and communities which connect us to the natural world, and support both personal and planetary health. He brings this vision, experience and commitment to a collaborative design process, with the goal of profoundly understanding the interconnections between people, place, and systems that generate the best solution for each unique project. Marc teaches a 10-week course,Zero Net Energy Homes, where students walk away with a comprehensive understanding of all of the key components of a zero net energy home, do a full design of a Zero Net Energy Home, and earn NESEA’s ‘Zero Net Energy Homes Professional Certificate.’ The next course starts on September 15th.

Read the full course outline of Zero Net Energy Homes and learn more here.
The course is capped at 50 students with 30 discounts.



Posted in Building Efficiency, Q+A | Leave a comment

HeatSpring Launches “Ask An Expert” Services

Today’s we’re launching a quick and simple but important addition to our extensive library of free articles, white-papers, tools and free courses, and it’s called HeatSpring’s Ask An Expert service. The Ask an Expert service is for both clean energy professionals and property owners that need help with a very specific situations related to clean energy.

Our industry certification and continuing education trainings have always provided the students of each course with direct contact with our instructors through forums, our message boards, and direct face to face contact. But what happens after the class is finished? What happens if you run into a specific problem while doing a site visit? If you have a question when writing a proposal, creating a design or during commissioning of a project? What happens if you’re brought into a project that is having trouble and your task is to determine what is wrong? We think our Ask An Expert portal will help you.

There is value in simplicity, speed, and curation. There’s a lot of information on the internet but a lot of the information does not fit YOUR SPECIFIC SITUATION. Many times it’s hard to find an answer for a complex problem and we want to use our community of readers, students, instructors, and partners to help each other all the time.

Our goal at HeatSpring is to provide renewable energy professionals and property owners with all the information you need to make money or save money using clean energy. We realize that sometimes professionals and property owners have specific questions that cannot be addressed in HeatSpring Magazine, in a industry certification training, or in a free course. For this reason, we created Heatspring’s Ask An Expert service. The service is both for professionals and property owners.

CLICK HERE if you are an INDUSTRY PROFESSIONAL – engineers, tradesman, salesperson, architect, executive – looking to ask a question.

  • The professional section is split up in technology sections, within each section, feel free to ask any question about marketing, sales, design, installation, project management, policy, and finance.
  • We’ll work to get you an answer within 48 hours.

CLICK HERE if you are a PROPERTY OWNER that is looking to ask a question related to the design, installation, policy, or financial implications of investing in clean energy.

  • The property owner section allows you to send us a specific question and we’ll respond to it within 48 hours. We didn’t feel it would make sense to make this information public because it can involve sharing private information about your home including addresses. etc.
Posted in Geothermal and Solar Design and Installation Tips, Geothermal Heat Pumps, Q+A, Solar and Geothermal Sales and Marketing Tips, Solar Photovoltaics, Solar Thermal | Leave a comment

Top Alternative Energy Articles of 2011: Companies Love Technology but want Sales

2011 was an amazing year for renewable energy. All industries had impressive growth, product innovation, and business model innovation.

Here are the top 10 posts from HeatSpring Magazine in 2011, based on the number of reads each post received, and our favorite posts. The data is skewed by two items. First, older posts clearly had more time to accumulate reads. Second, some posts were featured on our monthly newsletter which drastically increases hits.

Here’s what I’ve noticed about what’s most interesting to people. While the main challenge companies are facing is getting their first sales or increasing sales and maintaining profitability, readers seem more interested in articles about technology. This makes sense. In order to be confident about selling and creating an efficient sales process, you must understand how a project is designed and installed.

Here are the Top 10 Posts

  1. Top 50 Most Efficient Geothermal Heat Pumps
  2. A Simple, 4 Step Guide to Designing Geothermal Systems
  3. Top 5 Ways to Spot a Bad Roof in a Solar Assessment
  4. Three Most Common Mistakes Made by Geothermal Designers
  5. Top 50 Most Efficient Solar Thermal Modules
  6. 11 Tips for Proper Manual J Calculations
  7. 10th Anniversary Geothermal Survival Kit
  8. Geothermal Powers the Statue of Liberty
  9. How to Overcome the Top 5 Objections in Selling Solar and Geothermal
  10. 3 Things you May Not Know About Solar PV Sales
Posted in Q+A | Leave a comment

Q+A with Solar Thermal Expert Bob Ramlow: Hard Water Issues, PV Powered Solar Thermal and Best Practices with Air Venting

Before, during, and after our trainings students ask our instructors many detailed and specific questions. These are questions that are useful to anyone who is involved in the design and installation of renewable energy systems. At HeatSpring, we’ve always felt it would be useful to spread this knowledge to others who could not have the benefit of attending the course.  However, until now, we have not found a way to efficiently spread this information.

For each course, we’ve created a closed forum that only students have access to, both before and after the training has finished. The forums give students direct contact with instructors in addition to the time they’ve spent together during the training.  They can use it ask the instructors very specific questions, share docuemnts and plans and schedule phone conversions if the email and forum’s are not helping them. From these interactions, we will be picking some of the best questions and sharing them with you.

In this issue, three questions will be addressing three question Bob Ramlow was asked.

  1. Is hardwater an issue with closed loop solar thermal systems?
  2. Are solar pv powered solar thermal systems cheaper and easier to operate then traditionals powered ones?
  3. What are the best practices for placement of automatic air vents in solar thermal systems?

Continue reading

Posted in Geothermal and Solar Design and Installation Tips, Q+A, Solar Thermal | Leave a comment