9 Principles Of Integrated Project Delivery by Positive Energy

Our mission at Positive Energy is simple - we want to change the way the built environment is delivered. Part of that transformation happens when we work through projects differently, emphasizing the strengths of each key player involved. It's not always easy, but it makes sense. And the AIA knows this too. They have a name for this process and have even laid out fundamental principles to move it along. 

It's important that we all know these principles, infuse them in our process, and use them to strengthen and benefit our projects. Our Integrated Mechanical Designs are performed with these principles woven into each decision made along the way. It's a no brainer. Here are the fundamental principles of Integrated Project Delivery as defined by the AIA (California Council). 

1. Mutual Respect & Trust. 

Mutual Respect & Trust. In an integrated project, owner, designer, consultants, constructor, subcontractors and suppliers understand the value of collaboration and are committed to working as a team in the best interests of the project. 

2. Mutual Benefit & Reward.

Mutual Benefit & Reward. All participants or team members benefit from IPD. Because the integrated process requires early involvement by more parties, IPD compensation structures recognize and reward early involvement. Compensation is based on the value added by an organization and it rewards “what’s best for project” behavior, such as by providing incentives tied to achieving project goals. Integrated projects use innovative business models to support collaboration and efficiency. 

3. Collaborative Innovation & Decision Making.

Collaborative Innovation & Decision Making. Innovation is stimulated when ideas are freely exchanged among all participants. In an integrated project, ideas are judged on their merits, not on the author’s role or status. Key decisions are evaluated by the project team and, to the greatest practical extent, made unanimously. 

4. Early Involvement of Key Participants.

Early Involvement of Key Participants. In an integrated project, the key participants are involved from the earliest practical moment. Decision making is improved by the influx of knowledge and expertise of all key participants. Their combined knowledge and expertise is most powerful during the project’s early stages where informed decisions have the greatest effect. 

5. Early Goal Definition.

Early Goal Definition. Project goals are developed early, agreed upon and respected by all participants. Insight from each participant is valued in a culture that promotes and drives innovation and outstanding performance, holding project outcomes at the center within a framework of individual participant objectives and values. 

6. Intensified Planning.

Intensified Planning. The IPD approach recognizes that increased effort in planning results in increased efficiency and savings during execution. Thus the thrust of the integrated approach is not to reduce design effort, but rather to greatly improve the design results, streamlining and shortening the much more expensive construction effort. 

7. Open Communication.

Open Communication. IPD’s focus on team performance is based on open, direct, and honest communication among all participants. Responsibilities are clearly defined in a no-blame culture leading to identification and resolution of problems, not determination of liability. Disputes are recognized as they occur and promptly resolved. 

8. Appropriate Technology.

Appropriate Technology. Integrated projects often rely on cutting edge technologies. Technologies are specified at project initiation to maximize functionality, generality and interoperability. Open and interoperable data exchanges based on disciplined and transparent data structures are essential to support IPD. Because open standards best enable communications among all participants, technology that is compliant with open standards is used whenever available. 

9. Organization & Leadership.

Organization & Leadership. The project team is an organization in its own right and all team members are committed to the project team’s goals and values. Leadership is taken by the team member most capable with regard to specific work and services. Often, design professionals and contractors lead in areas of their traditional competence with support from the entire team, however specific roles are necessarily determined on a project-by-project basis. Roles are clearly defined, without creating artificial barriers that chill open communication and risk taking.

Comfort With A View - Building Science Philosophical Society by Positive Energy

Greetings building science enthusiasts! 

Now that we're well into summer and it's scorching hot outside, we should talk about heat and windows. We've all seen those little stickers that come on new windows, but what do they mean? 

Join us Thursday July 28 at the offices of Building Exterior Solutions as architect Adam Pyrek of The University of Texas School of Architecture and CINCO Labs leads a discussion. We'll break down what NFRC window stickers mean, how your windows' U Factors are tested, how they affect you and your clients. We'll even have a live window testing hot box so you can come kick the tires (not literally, but you get it). 

You won't want to miss this one!

Comfort With A View - led by Adam Pyrek

3709 Promontory Point Drive, Suite 206 | Austin, TX 78744

Thursday, July 28, 2016
4:30 - 6:00PM

Because discussing the built environment is crucial!

Bring your own beer and an open mind for the best possible experience.


PHAUS Austin Chapter by Positive Energy

We are very proud of the efforts of the local PHAUS chapter here in Austin. Do yourself a favor and read a message from the president, Eric Griffin. You may recognize him because he's one of our very own here at Positive Energy! Check out the organization's website here

"Austin is an intelligent, thoughtful, vibrant and progressive city that in many ways has lead the nation in local energy efficiency standards and high performance construction.  However, engaging the community and creating a Passive House culture in a hot and humid climate has been a challenge. As conventional dialogue for high performance buildings has focused on heating dominated climates with minimal consideration of hot and humid climates with substantial cooling loads, the old Passive House standard was a non-starter for the design and construction leaders in our market.  Thankfully, PHIUS released the PHIUS+2015 building standard, which has reinvigorated our chapter. There's finally a climate zone appropriate, economically justified, performance based reason to re-think your perception of Passive House. We all understand that thoughtful design and implementation of building science principles is imperative for successful outcomes for owners and occupants in humid climates, finally there's a Passive House organization that does, too." 

Building Science Philosophical Society Meeting Announcement by Positive Energy

Our homes and buildings are complex systems of systems that have a significant impact on our lives -code requirements for their design and construction directly impact our health, our comfort, our safety and our bank accounts.  

Please join us for our next Building Science Philosophical society meeting next Thursday on 4/7, where the matter at hand turns to something we all have an opinion about - building codes*.

Strong, well-designed, effectively enforced building codes can save lives, save energy and reduce resource use. It's also true that building to code minimum standards leads to the worst building that can be legally built.

Complicating the question of Codes is that there are now a host of beyond-Code programs to choose from - see the icons below. Even assuming the "perfect" code, the elephant-in-the-room is effective enforcement. Beyond all this, how do shifting societal values and owner/occupant preferences affect this mix? 

Please join us for a lively and thoughtful discussion... It's even rumored that our local Austin Energy Code 'Czar' will be on hand to share his thoughts and opinions!



Thursday, 4/7/16 

Positive Energy

1206 B South 3rd

Austin, TX 78704

*The emphasis for this discussion will be on those building code provisions that specifically impact the long term performance (health, comfort, energy use, durability) of the building. 

Sustainability Through Integrated Design - COTE San Antonio Event! by Positive Energy


Integration Matters - Integrated Project Design and Delivery

Is “Integrated” the new Green? The term is appearing everywhere. What does it signify for the industry and what does it mean for you? Prominent in the modern architectural lexicon, Integrated project delivery (IPD), Integrated design process (IDP) and Integrated design teams (IDT), all have a common aspiration - achieving multiple simultaneous positive outcomes through a process of expanding the project team’s understanding of interlocking impacts.  

Applied to buildings, the core meaning of integrated points to two key categories of outcomes that represent the why we pursue and this approach. 

They are: (1) human factors - a healthy, safe, comfortable indoor environment to support the occupants productivity and well-being; and, (2) societal factors - reduced resource and energy impact to support the owners/operators desire for reduced maintenance and long terms cost of ownership (as well as societal goals as expressed by Codes). 

How we approach the project delivery process is to integrate desired outcomes from four interlocking aspects of the project: (1) the architectural vision for the building; (2) the human factors of health, comfort and well-being; (3) the design of the enclosure; and, (4) the strategy for climate zone appropriate mechanical systems. A mutual and sympathetic understanding of these four facets leads to success in achieving project goals. 

What we are integrating is a project delivery approach. Specifically a project delivery approach that harnesses the expertise and perspective of the entire team of stakeholders to optimize project outcomes so that they increase value to the owner and occupants, while reducing resource use through maximizing efficiency. 

Please join us for this workshop and discussion to learn about and share thoughts on building design and delivery.


2016 ACI National Home Performance Conference & Trade Show by Positive Energy

The 2016 ACI National Home Performance Conference and Trade Show is coming to Austin, TX April 4-7! Mark your calendar and make your plans to join us for an exciting experience, from the best educational agenda in home performance and weatherization to networking opportunities like none other. This conference is being held at the Hilton Austin in the heart of downtown.

Click here for more information.

There is also an offer to volunteer to staff the event and get a free admission(!). These volunteer slots are limited so act fast if you want one. If interested contact Bethany Dittmar.

Building Systems & Technology Group - February 25 by Positive Energy

Greetings building science enthusiasts!

We all have a real sense (at least we hope) of what we put into our bodies when we eat food. We know that fruits and vegetables are vastly more nutritious than a cheeseburger with fries. When we're in the built environment though, and especially the homes where we want to feel most safe, the damaging effects of harmful materials are still just as present and dangerous, yet somehow given less attention. The imperative to change that discourse falls to those who pay attention and care. 

Join us this Thursday, February 25th, as Wade Mullin, M.S., P.G. , IAC of the Building Services Department with the City of Austin leads us in a discussion on Lead & Asbestos in buildings. 

What: The Building Systems & Technology Group

When: Thursday, Feb 25, 4:30 - 6:00 PM

Where: Positive Energy's office, 1206 B South 3rd, Austin, TX 78704

What else: BYOB & an open mind and your own stories/ideas


BEC National Symposium Topics by Positive Energy

The BEC National Symposium has some great sessions lined up this year. Be sure to get your ticket now and head to Austin, TX in May.

Historical Perspectives on Enclosures
Larry Speck, FAIA


This session will examine some time-honored principles and practices regarding the design of building enclosures as well as options that often seem to disappear and re-appear in the guise of advancement. What are we not learning? What can we learn from the past that will carry us forward?

We will examine several enduring truths regarding designing enclosure that have been pervasive through history and will examine how different eras have dealt with them to their benefit or disadvantage.

A Building Scientist’s Perspective on the Building Enclosure
Dr. John Straube, Keynote

Project teams use their understanding of the enclosure to deliver good buildings to their clients. This understanding is based on the function of the assembly in relation to the climate, Codes and physical laws relating to heat, air and moisture flows across the enclosure. This seminar focuses heat transfer across the building enclosure. The mainstream understanding of heat flow across building assemblies is based on layers of simplifying assumptions. Do these simplifications distort our understanding of what is implicitly a complex, interconnected, three-dimensional process?

Think About This
Two-Guys on Your Head
1 LU

We evaluate, design, and construct environments that consist of complex building materials and systems, but are our thought processes inhibiting or enhancing our ability to make wise decisions? Do we have sufficient knowledge in how the environments we create affect the occupants and users of those environments? Understanding how we process information may assist us in deciding whether we continue delivering buildings the way we have always done it or do we join the voices that advocate for change.  In this session, Dr. Bob Duke and Dr. Art Markman, along with Rebecca McInroy, will give us insights into understanding how our brains work so that we may better manage our daily decision making and better manage changes in our industry.

Best Practices for Enclosure Design from the Perspective of Hygrothermal (heat &moisture) Analysis
Dr. Achilles Karagiozis
1.5 LU/HSW

Clients and owners are demanding building with enclosures that align with outcomes of high thermal comfort, reduced energy costs and increased durability. To achieve these goals, project teams must appreciate the importance of heat and moisture flow on the assemblies they design. With modern materials and increased expectations in the marketplace, avoiding thermal bridging and tightening air barriers is only part of the answer. This seminar will provide both an introduction to hygrothermal analysis and its application to real world assemblies.

Case study opportunity: Dedicated dehumidification using novel split system dehumidifier (Ultra Aire SD-12) by Positive Energy

Greetings building science enthusiasts,

Exciting opportunity to consider. UltraAire is looking to provide an SD-12 (http://ultra-airecontractor.com/ultra-aire-sd12.html) to one lucky home in Austin in return for access to the home, data from the project, client interviews and (probably) some pictures. Project goals will be to gauge the impact of the SD-12 on overall comfort, health, durability and energy use. 

The ideal house is in the 2500-3000SF range and will have a ducted HVAC system operating in a *single zone* configuration.

Send an email to: SD-12@positiveenergy.pro if interested in this opportunity. Act quickly, the project research team wants to get started! Only one home will be selected. 

March 2 BEC Meeting - Radiant Cooling & Heating Presentation By Messana by Positive Energy

Hydronic radiant cooling systems have been used worldwide for decades. Now they are gaining popularity  in North America and become an effective alternative to traditional all-air systems. New building codes and regulations demand for more energy efficient HVAC systems and radiant cooling is a proven and effective technology for cooling residential and commercial buildings. It is the preferred choice for designers to meet standards of Passive House, NetZero energy buildings, green and sustainable architecture. This presentation will address common questions and concerns and also analyze some of the benefits in terms of thermal comfort, wellbeing and productivity of occupants as well as substantial reduction of ductwork cross-sectional dimensions, operational and maintenance costs. Several case studies of radiant cooling projects will be presented.

Join us March 2, 2016 at the Austin AIA for the Building Enclosure Council meeting on Radiant Cooling & Heating Systems presented by Messana. 

801 W 12th St, Austin, TX 78701


January 14 Meeting of The Building Science Philosophical Society by Positive Energy

Join us Thursday, January 14th, 2016 for our inaugural meeting to discuss the notion of radiant cooling and heating panels in the marketplace and how the Messana Company out of Santa Cruz, California is meeting the emerging market demand. 


Thursday, January 14, 2016


4:30 - 6:00 PM 


Positive Energy's Office
1206 B South 3rd
Austin, TX 78704

Who To Bring? 

Yourself and anybody else who is interested in building science.

What To Bring?

Bring your mind and whatever your choice libation, we'll have cooler space


Building Science Panel Discussion Announcement by Positive Energy

Event: Historic homes, Modern Performance

  • Location: Austin AIA, 801 W. 12th St. Austin Texas 78701

  • Panel: 

    •      Andy Ask, P.E.

    •      Joe Pinnelli

    •      Jennifer Doyle, P.E.

  • Date/Time:  Tuesday, December 12/8/2015, 430-600pm

  • Schedule: Drinks, snacks and networking 430-5pm, panel discussion 5-600pm

  • AIA CEUs, 1 LU/HSW available

Panel Description:

A comfortable, durable, efficient home with excellent IAQ is the goal of every project team. Confidently achieving these performance dimensions in a historic home remodel requires working an integrated design process, based on building science principles that recognize and account for the interactions of the climate, the enclosure and the mechanical systems.  

Upgrading systems and assemblies in historic homes offer unique and often confounding challenges on both the enclosure and mechanical system sides and working in a hot-humid climate zone means the stakes are high to get it right. 

Please join us at AIA for a seminar on applying the basic principles of heating, cooling, dehumidification and ventilation to challenging historical homes projects. Opportunities to share a discussion with speakers that have this depth of experience are rare, don’t miss this one. 

Andy Äsk

Andy Äsk has been called ‘one of the best HVAC minds in the country’ and is the author of the seminal text on mechanical systems for moisture control “H2-No”. He is also an engaging speaker with a sense of humor and a broad building science based perspective on the industry. In his role as consulting engineer in Cape Coral, Florida, he specializes in diagnosing, remediating, and retrofitting of existing HVAC systems for the purpose of improving performance, energy efficiency, and Indoor Air Quality. His work requires a deep understanding of both mechanical system capabilities and their interaction with building enclosures and (typically) humid climates. His practice includes the preparation of MEP (Mechanical, Electrical, and Plumbing) design documents. He occasionally writes for trade publications.

Joe Pinnelli, CEO J Pinnelli Company LLC

Joe is a national treasure in the historic retrofit and high performance retrofit community. He is a 36-year veteran general contractor with vast experience in solving problems, suggesting cost effective pathways, coordinating with professionals, resourcing materials, subcontractors and suppliers. A leading authority on restoration protocols, Joe has dedicated his career to increasing the performance of historic structures. He passionately pioneered Green Building and Building Science in Austin by incorporating advanced building practices into all projects whether new construction, renovations, or restoration.

Jennifer Doyle 

Jennifer Doyle is the Principal Engineer, Roofing & Waterproofing Consultant at Engineered Exteriors, PLLC. She has previously owned JCD Consulting, Subconsultant to Jim Whitten Roof Consultants, LLC,  and worked as a staff engineer at Law Engineering and Environmental Services, Inc. 

Building Science Seminar Announcement with Andy Äsk by Positive Energy

Event: Building Codes & Moisture Control in Humid Climates

  • Location: Austin AIA, 801 W. 12th St. Austin Texas 78701

  • Date/Time:  Wednesday 12/9/2015, 12-1pm

  • Speaker: Andy Äsk, P.E., J.D.

  • AIA CEUs, 1 LU/HSW available

Course Description: 

The need for fresh air in a home is not new. Ever since man brought fire  inside we have recognized the need for ventilation. What is new is the industry commitment to build homes to codes that seek to fully isolate the great outdoors from the indoors. Reliable control layers have many performance benefits as well as many unintended consequences.  This session will address how modern energy and building codes can lead to moisture issues in homes and buildings, especially during part-load conditions, which exist the majority of the time.

Potential health, comfort, durability and sustainability issues with the implementation of code and beyond code practices will be discussed. The advantages and disadvantages of mechanical equipment options and control strategies, understanding the capabilities and limitations of the HVAC system, the benefits of a dedicated dehumidification and why it can be more cost effective than air conditioning alone are each key pieces of understanding for design and construction teams working in hot-humid and mixed-humid climates. 

Andy Äsk has been called ‘one of the best HVAC minds in the country’ and is the author of the seminal text on mechanical systems for moisture control “H2-No”. He is also an engaging speaker with a sense of humor and a broad building science based perspective on the industry. In his role as consulting engineer in Cape Coral, Florida, he specializes in diagnosing, remediating, and retrofitting of existing HVAC systems for the purpose of improving performance, energy efficiency, and Indoor Air Quality. His work requires a deep understanding of both mechanical system capabilities and their interaction with building enclosures and (typically) humid climates. His practice includes the preparation of MEP (Mechanical, Electrical, and Plumbing) design documents. He occasionally writes for trade publications.

The Neglected Blog! Positive Energy Updates! by Positive Energy

Building Science enthusiasts, please accept our humble apology for neglecting this little corner of the web! We've been quite busy here at Positive Energy, but there are a few items that we'd like to note. These are primarily company updates from the summer to keep you in the know with what we're up to.

Building Science Summer Camp 

Every summer (August 3-5, 2015), the best minds in the industry all gather in Westford, MA Annual Westford Symposium on Building Science. This year's meeting was absolutely fantastic and there was even a session called "How Sausage Actually Gets Made" Obviously, it was a wild time. Big thanks to The Building Science Corporation for hosting such a great summer camp.

Radiant Heating & Cooling

This update is pretty simple. We're happy to let the world know that we're working on our first Alpha test project for our developing design product, Radiant Heating & Cooling. Stay tuned for more pictures and updates as this project gets into full swing.

The Building Science Podcast

This is by far the most exciting new undertaking that we've taken on as a company and we're thrilled with the initial momentum that it's had. We've officially posted 8 episodes now and have planned out the next year's worth of content, topics, interviews, etc. 

PLEASE check it out on iTunes

New Conference Table

Not that it's of huge significance, but we got a pretty awesome new conference table and we're excited to sit around it to have our next meeting with you. 

Stay tuned for more updates and a few crunchier posts on building science topics. In the mean time, if you haven't checked out the podcast, please don't hesitate! Listen to it all you want! 

Windows & Comfort - Live Broadcast From The AIA Food For Thought Series by Positive Energy

Positive Energy, Tanteri + Associates, and Cardinal Glass are excited to announce this upcoming seminar to discuss one of the most impactful pieces of a design - glazing. Join us live at the Austin AIA headquarters for a thoughtful presentation and a few surprising demonstrations. Don't miss this incredible opportunity to establish yourself as an industry leader and contribute your voice to a rich dialogue. 


To view the video, tune in between the hours of 11:30 AM and 1:PM on Monday July 6. To view the event in Google or on YouTube, follow this link. For technical inquiries, contact Miguel Walker from Positive Energy at miguel@positiveenergy.pro

The Basics of Phase Change Materials by Positive Energy

Originally authored By Kristof Irwin, edited for blogging format

With our upcoming Building Science Happy Hour focusing the topic of phase change materials, we wanted to provide some information on the basics. This blog post will take a look at phase change materials (hereafter referred to as PCM) in lightweight building assemblies.

Performance testimonial of the effects of Phase Change Materials to an existing structure. Church personnel give their views of the positive effects that bioPCM can have on the energy savings of a structure. This is a product of Phase Change Energy Solutions.

PCM Technology Background Information

PCMs are latent heat storage materials. Unlike insulation, which only retards the flow of thermal energy through a structure, PCM absorbs heat and stores it in the molecular structure of the material. If this heat can later be shed passively to the exterior, building energy use can be decreased. PCM can also be used at interior surfaces to stabilize interior temperatures by absorbing and releasing heat as it stays in solid (frozen) state at room temperatures.

Research and development on the application of both active and passive PCM to the built environment has been ongoing for years. There are both organic and inorganic PCM products either available commercially or under development. Inorganic compounds include salts and salt hydrates and eutectics. Organic materials include paraffins, fatty acids and sugar alcohols. PCM selection depends on many factors, including: phase change temperature and transition characteristics, energy storage density, thermal conductivity, material stability, compatibility with construction materials and process, long lifetime, non- toxicity and inflammability, and pricing and availability.

Recent R&D work in organic PCMs based on proprietary mixtures and processing of organic extremely pure fatty acids has created a product with precise, controllable transition temperatures, natural fire suppression characteristics and a high energy/enthalpy storage density. The product also integrates easily with existing building techniques and is priced to make it cost effective, with reported ROIs of 2-4 years.

The candidate product currently under consideration is called BioPCM and is manufactured from a combination of soy and palm oil by Phase Change Energy Solutions Inc. The product has 3 lines of PCM with increasing energy storage densities. These are referred to as M-27, M-51 and M-91, where the “M-factor” is similar to R-value but include latent heat storage effects (these behave similarly to a mass effect, thus the “M”). M-27 is specified to store 27BTU of latent heat per square foot. In addition, each of these products can be specified with a phase transition temperature of 73, 76, 79 or 84° F, these are known as Q-values. Selection of M-factors and Q-values is based on building load characteristics, installation considerations, local diurnal temperature cycles and interior set point temperature. The M-27 and M-51 products with Q-values of 79 and 84 are the primary selections for local designs. These materials can be installed on any building envelope surface.

Improving Comfort & Performance

PCM acts to absorb heat flow through the building envelope and to stabilize interior temperatures, particularly surface temperatures. These effects improve building comfort and reduce the energy needed to run mechanical systems to heat/cool the building. By delaying and offsetting thermal load to the building, PCM also performs peak load shifting. Studies have shown energy savings of 20-50% relative to reference buildings without PCM. The chart below show the results of energy monitoring in a side-by-side study summertime study near Phoenix, Arizona. Note that Arizona typically has less humidity than central Texas typically and there for experiences a wider range of diurnal temperatures, which allow for full recharge of the PCM each night. Full recharge, physically re-freezing into solid form, of the PCM is a prime performance consideration in central Texas.

Measured energy consumption of identical buildings tested during summer conditions. The control has no PCM. (Ref: BioPCM manufacturer literature) 

Measured energy consumption of identical buildings tested during summer conditions. The control has no PCM. (Ref: BioPCM manufacturer literature) 

PCM & Modeled Energy Performance

Positive Energy is currently investigating the capacity of PCM to offset the increased cooling due to high SHGC values and radiant heating effects, most notably in the rooms with significant glazing loads, as these are dynamic and tend to dominate comfort during critical times of the day.

As a reminder, under the Performance Path the IECC2009 preserves three mandatory prescriptive requirements:

1. Envelope leakage (ACH50 < 7)
2. Duct leakage (8/12 CFM25 of leakage per 100 SF CFA)
3. Area-weighted SHGC of 0.5 (relaxed from 0.3 in Prescriptive Path).

The strategy for projects has been to show the ability for PCM to offset the glazing load by storing incident radiant energy and re-radiating this heat to the exterior.

In addition to reviewing the open literature on PCMs, we have been working with University building science labs to understand PCM function in our climate zone, and with energy modeling software vendors to model the impact of PCMs on energy use.

Consultations with PCM researchers at UT’s Cockrell School of Engineering offer confirmation of the effectiveness of the both the passive and active PCM scenarios, and that more quantitative research is needed to validate the passive PCM concept in our local climate zone (2A). One specific concern is the relation of the material transition temperature and local diurnal temperature swings. This concern is directly related to both the sharpness of the phase transition and the transition temperature. Based on local TMY data the Q-84 product will be able to recharge (re-freeze) during Austin summer conditions, where the highest night time low temperatures are typically near 79°F.

Repeated interactions with Architectural Energy Corporation (AEC) have led to the conclusion that their REM/Rate software can not accurately account for the latent storage of PCM. The recommended strategy has been to model PCM as additional R-value. Because the Treehouse envelope already has envelope R-value above R-21 in all non-glazed surface, the effect of additional R-value is extremely limited. We are hitting the flat part of the hockey stick curve as shown below. Because of this, the actual performance of PCM will exceed the modeled performance shown in the next section.

Chart showing the reduced impact of additional R-value for high-quality building envelopes&nbsp;

Chart showing the reduced impact of additional R-value for high-quality building envelopes