Passive House Energy Modeling: Project Boost
Boost your project comfort and efficiency with energy modeling. Balance high-performance building cost, Passive House principles, and budget.
Informed Decisions Meet Goals and Save Money
- Quantify the benefits of envelope upgrades
- Control diminishing returns, and avoid overspending
- Strategically identify products you actually need, and discard those you don’t
- Significantly reduce mechanical system size
- Balance initial investment with lifetime operational savings
- Balance your budget for the goals you prioritize (e.g., indoor air quality and comfort vs. energy efficiency)
What Is Passive House Energy Modeling?
Passive House energy modeling is a powerful process that helps predict how a building will perform before it’s built. It focuses on energy use, thermal performance, mechanical loads, and indoor environmental quality.
Whether you’re designing a custom home or a commercial project, passive building energy modeling allows you to make informed decisions about envelope assemblies, HVAC systems, and product selection. Unlike code-minimum checklists and simplified energy models, this approach provides actionable insight to drive budget decisions, real efficiency, and occupant comfort.
Building Performance: Focus on What Matters
Depending on the type of project, its location, climate zone, and overall performance goals, we determine the most important parameters to evaluate during the passive building energy modeling. Based on our professional experience, we select these parameters for what is going to be most impactful and insightful for the project. Consequently, we help teams focus on aspects of the building that are most meaningful and disregard what is just noise.
To list a few, parameters that we typically evaluate in the Passive House energy model, and that impact the results of a high-performance project, include:
- R-value Targeting – find the “sweet spot” for optimal insulation levels in the building envelope assemblies
- Selection of Windows + Exterior Doors
- Glass Solar Control – determine the best low-e coating to optimize the building for year-round performance (Summer + Winter)
- Building Airtightness
- Shading, e.g., overhang depth vs. adjustable interior or exterior shading
- Specific parameters for commercial buildings, as well as retrofit projects
- For the three main parameters considered in the Boost building analysis, we evaluate incremental levels of performance such as:
- Code-minimum compliance baseline
- Good
- Better
- Best
This gives us a clear response on how the building performs, and whether or not we need the higher level of performance.
Results of the Passive House Energy Analysis for a High-Performance Project
The combinations of the parameters listed above yield about 40–60 scenarios that get modeled for a single project. This process maps out the project performance under different key metrics, which gives teams the full picture for the further development of the project.
For each of the combinations described above, the Boost Report includes the following results:
- Energy savings for heating + cooling compared to the baseline*
- Reduction of PV system size to get to Net Zero compared to the baseline*
- Heating and cooling loads
*Baseline: building to code-minimum (for new buildings), or existing conditions (for retrofits).
Passive House Energy Modeling and Certification
- For projects seeking Passive House certification, building energy modeling is the first step in the process. With the support of the Passive House energy modeling process, the team develops the project to meet the stringent certification requirements.
- Ideally, passive building energy modeling is brought in at an early design stage (e.g., schematic design), before the construction details are finalized.
How Close Are We to Passive House Performance?
Among other results, the Boost Report includes the benchmarking of the building performance against the following Passive House standards:
- PHI Passive House
- Low Energy Building (new builds) or EnerPHit (retrofits), as applicable
Based on our Report on Building Standards, the PHI Low Energy Building standard performs similar to, and slightly better than, the Phius standard. For projects interested in Phius benchmarking, the PHI Low Energy Building standard is an accurate alternative.
Passive House Energy Modeling for Projects Not Seeking Certification
- Contrary to popular belief, 4 out of 5 teams that choose Emu’s Project Boost are not actually seeking Passive House certification. Passive House provides the advanced building science-based handrail for project teams to make informed decisions on high-performance goals, innovative products, and the associated budget decisions.
- Consequently, these teams use the results of the energy analysis to make informed decisions for their projects and meet their high-performance goals within their budget.
Aligning with Net Zero Goals
If your project aims for Net Zero, Passive House energy modeling provides a strong foundation. We help you:
- Lower demand so you don’t oversize renewables
- Evaluate the cost-effectiveness of efficiency upgrades vs. solar
- Set realistic energy targets aligned with climate and budget
Net Zero building energy modeling supports informed decision-making at every step.
Understand Your Building’s True Budget Drivers
Too often, teams either under- or overspec due to lack of accurate data. Too often, important design decisions are made by following prescriptive checklists (e.g., building code or “green building” checklists) that have little to do with the specifics of your project, your site, and your climate.
Passive building energy modeling isn’t just about performance—it’s about making informed decisions that affect your budget. Energy modeling early in the design of your high-performance building helps you:
- Avoid overspending on insulation or HVAC
- Optimize heating + cooling systems for right-sizing and low-load building performance
- Prioritize high-impact upgrades that deliver long-term value
Whether you’re managing a Passive House cost plan or working on a high-performance building budget, this step brings clarity to cost vs. performance trade-offs.
Make Informed Design Decisions That Save Money
At the schematic stage, design choices can make or break the project’s long-term value. We help you:
- Optimize performance targets for your climate (e.g., best R-values for building assemblies)
- Identify specifics for building components you need, including window package, ERV/HRV, HVAC, and others
- Understand the impact of design changes on project cost and energy use
- Avoid common pitfalls that lead to redesign or cost overruns
- Avoid picking products that won’t meet your project goals, and avoid being stuck with an underperforming building (including moisture issues, thermal discomfort, and low air quality)
- Avoid overspending on products that you don’t need or that would perform poorly in your climate
The budget planning for a high-performance building and Passive House starts with solid building science-based information—and we help you get it.
The Failure Of Prescriptive Methods
It’s fair to say that even “high-performance” prescriptive methods have little to do with your project. A prescriptive approach is like talking to someone that knows all the answers before you get to ask your questions. The value that can provide in real life is really limited.
In our Report On Building Standards, we evaluated 50 single family home projects across the US – the study is available for free download on our website.
In one section of the study, we selected 18 projects where a prescriptive approach (2021 Phius Prescriptive) would yield similar results to a performance-based one (PHI Low Energy Building). Using one standard or the other would result in similar energy performance, within a 20% difference margin.
Our market analysis demonstrated that:
- The prescriptive approach (2021 Phius) systematically over spec’d insulation, causing diminishing returns
- The performance-based approach (PHI Low Energy) allowed to significantly improve the building performance at virtually zero extra cost (e.g. selecting the right low-e coating on the glass)
- The performance-based approach allowed to eliminate in average over 800 cubic feet of insulation per project
- Even including the actual modeling fees of the Project Boosts we originally charged for those projects, using the performance-based method resulted in net savings of over $5,000 per project.
The report is available for free download on our website – look for the “Resource Efficiency” section of the report.
With Passive House energy modeling, you can:
- Quantify the benefits of envelope upgrades
- Control diminishing returns, and avoid overspending
- Strategically identify products you actually need, and discard those you don’t
- Significantly reduce mechanical system size
- Balance initial investment with lifetime operational savings
- Balance your budget for the goals you prioritize (e.g., indoor air quality and comfort vs. energy efficiency)
This helps control both Passive building cost and high-performance home budget with more precision.
Indoor Air Quality and Thermal Comfort
- Energy modeling isn’t just about BTUs and dollars—it’s about how the building feels to live or work in.
-
- Design for consistent indoor temperatures, no hot/cold zones
- Improve air quality with high-efficiency fresh air ventilation systems (ERV/HRV)
- Reduce allergens and contaminants through airtightness and air filtration
- Passive building optimization contributes to a healthier, more comfortable environment year-round.
Greater Indoor Air Quality Using Passive House Principles
- Implementing Passive House principles in any project can significantly improve the indoor air quality inside buildings:
-
- Protect from exterior pollutants (e.g., urban pollution, pollen, wildfire smoke)
- Remove interior pollutants (e.g., moisture, odors, CO2, VOCs, particulate matter from cooking, etc.)
- Provide a continuous supply of filtered fresh air to building occupants
- As a result, building occupants experience greater air quality inside the building, with a greater quality of life and satisfaction overall:
-
- Better sleep
- Greater productivity, energy, and focus
- Protection from seasonal allergens and urban pollution
- Protection from extreme pollution events (e.g., wildfire smoke)
- As part of the Project Boost, you’ll receive:
-
- A target air sealing goal for the project (ACH50 target)
- Detailed plans for the fresh air ventilation system (ERV/HRV) to be used for product pricing, consisting of:
-
- Fresh air supply/extraction register plan for each room of the building, including the associated airflow rates for each register
- System specifications including unit type and sizing (ERV or HRV, depending on climate), and subcomponents
- Air filtration strategy and recommendations
- Instructions on how to commission the system for it to perform as required
Passive Building Energy Modeling and Thermal Comfort
- Achieving high levels of thermal comfort is crucial for occupant satisfaction.
- Above all, many professionals underestimate the impact that windows and exterior doors have on interior surface temperatures inside a space, and their impact on thermal comfort.
- We utilize Passive House building science to analyze each individual window, exterior door, and skylight in the project (and doggy doors, too!). We assess their impacts on the energy balance and thermal comfort. In this analysis, we provide metrics for each window in the project on:
-
- Heat losses and thermal comfort
- Seasonal shading (incl. deciduous or evergreen vegetation, overhangs, etc.)
- Interior and exterior adjustable shading (depending on project specifics)
- Energy balance – Winter passive solar gains vs. Summer overheating risk
- As part of the Project Boost, you’ll receive:
-
- Recommendations on any significant changes needed for your window package and project design (i.e., any red flags we see)
- Detailed specifications for the window package to be used for pricing products, including:
-
- Target performance depending on your design and climate (i.e., phA, phB, or phC-grade products, incl. product lists)
- U-value, SHGC, and glass specs for optimal performance (Winter + Summer)
How the Passive Project Boost Works
- Submit your design – We review plans, elevations, and project goals
- Interview Call – We get together on a call and go over project goals, opportunities, constraints, and limitations
- Project-specific Estimate – Based on project size, type, and complexity, we issue a custom proposal for your project
- Energy model + analysis – We execute a full Passive House energy model of the project, based on your goals, our experience, and project- and climate-specific conditions
- Custom Boost Report – Includes detailed feedback on energy use, mechanical loads, and optimization strategies for your project
- Review Call – We get on a call to go over the project performance results together and review the recommendations on how to implement the most impactful changes into the design
Testimonials, FAQs, And Real Examples
- A client spent a few thousand dollars with Emu to run the Project Boost on their single family home project.
- We analyzed the early-stage concept design, and found that the assumed window package was only one of 3 options that would have met the client’s performance goals.
- By selecting the window package with the support of the Project Boost data, the client saved about $27,000 – which is considerably more than they spent on the Passive House energy modeling.
Emu’s Boost Report exceptionally detailed and informative. To be honest, I’ve not seen a report of this calibre before.
Anthony Jenkin, Outlier Studio
I’m ordering some windows for the first time and I’m scared. My project is not modeled and I feel like I’m just guessing. I hate that.
Owner-Builder
After honing in on an initial design, we decided to get expert input about the energy efficiency of the design. After much internet searching, we found Emu, and hired them for their Project Boost. One of the recommendations of the preliminary report was to simplify the geometry and move the mechanical room to the center of the home. We also simplified the geometry and surface area of the windows. We ended up with a better design in the end.
Matt Kirsch and Kerri Stroupe, Homeowners
Emu Boost Projects In North America
Our map of Project Boosts and Emu Pilot Projects shows all the places where we have analyzed projects for early-stage performance goal setting.
Ready to Optimize Your Building Design?
Whether you’re balancing Passive House cost goals, pursuing high performance on a budget, or aiming for Net Zero, the Passive Project Boost is a proven tool to guide better building decisions.
1.1k
American Pros Trained
95.4%
Passive House exam pass rate
4.7 / 5
Emu's training was relevant for participants' goals and responsibilities
4.8 / 5
Participants recommend Emu's Passive House Boot Camps