We will be honest—when someone mentions ASHRAE standards, most people’s eyes glaze over. Whereas here is the thing: after working on hundreds of HVAC projects, we have seen firsthand how getting these standards right (or wrong) can make or break a building’s performance. And more importantly, its profitability.
Last month, we reviewed a project where the team attempted to retrofit ASHRAE compliance after the fact. The result? A 40% cost overrun and a system that still doesn’t function properly. Compare that to a project we completed last year, where we integrated ASHRAE from day one, resulting in 24% energy savings, happy tenants, and the owner already planning their next building with us.
The difference? Timing and approach.
Two Projects That Changed How We Think About ASHRAE
The Oakland Office Tower That Got It Right
We were brought in early on a 12-story office project in Oakland. The architect was ambitious—LEED Gold, an aggressive budget, and a developer who had high utility bills had burned on previous projects. Instead of treating ASHRAE 90.1 and 62.1 as checkboxes, we utilized them as design tools.
The breakthrough came when we realized the building’s orientation and the owner’s plans for 24/7 operations meant traditional HVAC zoning wouldn’t work. By modeling energy recovery ventilators against the ASHRAE requirements early, we discovered a surprising finding: the “premium” energy recovery system costs less to operate than a conventional design.
The numbers do not lie: 24% energy cost reduction, LEED Gold certification, and the owner paid off the HVAC premium in 18 months through utility savings. But what mattered was walking through that building two years later and seeing people comfortable—no sweaters in summer, no complaints about stuffiness.
The Austin Science Building That Taught Us About Flexibility
University projects are challenging. Multiple space types, tight budgets, and occupancy patterns change every semester. This science wing presented an additional challenge: labs requiring precise environmental control were situated next to standard classrooms.
The game-changer was realizing that ASHRAE 55 and 62.1 do not have to work against each other. We designed a hybrid system with demand-controlled ventilation that treats each space type differently. Labs receive consistent air changes, and classrooms are equipped with smart controls that adjust based on actual occupancy.
The result? Thermal comfort is above 95% of the time, CO₂ levels that would make an IAQ consultant smile, and utility bills that do not give the facilities manager nightmares. More importantly, we learned that flexibility in ASHRAE compliance often matters more than perfect adherence to minimums.
Why ASHRAE Standards Matter (Beyond Compliance)
Here’s what we wish someone had told us earlier in our career: ASHRAE standards are not just regulatory hoops to jump through. They are the accumulated wisdom of thousands of engineers who’ve dealt with the same problems you are facing.
Take energy costs. In most retail buildings, HVAC systems account for 40-60% of total energy consumption. ASHRAE 90.1 is not just about meeting code—it is about keeping your client’s operating costs manageable for the next 20 years. I’ve seen too many buildings where the architect got rave reviews, but the owner is stuck with utility bills that make the building uneconomical to operate.
Indoor air quality hits differently now. Before 2020, indoor air quality (IAQ) was often an afterthought. Now, it is front and center, and insurance companies are asking questions. ASHRAE 62.1 compliance is not just good practice—it is liability protection. Additionally, there is growing evidence that proper ventilation can improve productivity enough to justify the associated energy costs.
The sustainability angle is becoming increasingly difficult to ignore. Whether it is local green building requirements or tenant demands, ASHRAE 189.1 is becoming table stakes for competitive projects. But here’s the twist: buildings that exceed these standards often command higher rents and have better tenant retention.
The Standards That Drive Design Decisions
ASHRAE 90.1: Your Energy Budget Reality Check
90.1 gets treated as a minimum standard, but innovative designers use it as an optimization tool. The standard essentially gives you an energy budget—how you spend it determines whether your building is a winner or a costly mistake.
The equipment efficiency requirements are just the starting point. The real value lies in system-level thinking. When you are forced to model energy performance early, you start to see interactions between the envelope, HVAC, and lighting that weren’t obvious before. I’ve had projects where meeting 90.1 requirements led us to rethink the building orientation and window design completely.
Pro tip: Do not wait for design development to run your 90.1 analysis. Running preliminary models during schematic design can shift your equipment budget toward higher-efficiency options that qualify for utility rebates. I’ve seen projects where the rebates covered 70% of the premium for high-efficiency equipment.
ASHRAE 62.1: Getting Ventilation Right Without Breaking the Bank
Here’s where many projects go wrong: they treat 62.1 as a minimum ventilation requirement and stop there. However, the standard is quite sophisticated in balancing air quality with energy consumption.
The key perspicuity is that outdoor air is expensive to condition. Every CFM of outdoor air in a hot climate adds to your cooling load. Every CFM in a cold environment adds to your heating load. The trick is giving people the fresh air they need without over-ventilating.
Demand-controlled ventilation is your friend here. CO₂ sensors are not just fancy gadgets—they are feedback systems that let you provide precisely the right amount of ventilation based on actual occupancy. I’ve measured reductions of 30-40% in ventilation energy on projects where we implemented proper demand control.
ASHRAE 55: Comfort That Works
Thermal comfort is a surprisingly personal experience, but ASHRAE 55 provides a framework that works for most people most of the time. The standard considers temperature, humidity, air movement, and radiant effects—basically everything that affects how comfortable people feel.
A common mistake we often see is designing for worst-case scenarios. You end up with oversized systems that can’t modulate properly, leading to temperature swings that make people uncomfortable. A better approach is to model comfort across various seasonal conditions and design systems that can adapt accordingly.
Here’s something interesting: buildings that consistently meet ASHRAE 55 comfort criteria have measurably higher tenant satisfaction scores. Happy tenants renew their leases, refer other tenants, and refrain from calling the facilities manager to complain about the temperature.
Making ASHRAE Work in Real Projects
Start Early, Really Early
The biggest mistake we see is treating ASHRAE compliance as a design development task. By then, you have already locked in major decisions about building orientation, window placement, and space programming. Changes become expensive and disruptive.
A better approach is to run preliminary ASHRAE analyses during the schematic design phase. It doesn’t need to be perfect when you’re looking for major problems and opportunities. Can you meet 90.1 requirements with standard equipment, or do you need to budget for high-efficiency options? Does your space programming create ventilation challenges that might drive up costs?
Model Early, Model Often
Energy modeling is not just about compliance—it is about understanding how your building performs. Tools like EnergyPlus and Trace 700 let you test different scenarios before committing to expensive equipment.
I’ve learned to run “what if” scenarios routinely. What if occupancy patterns change? What if utility rates increase? What if the owner decides they want LEED certification? Having models that can answer these questions quickly makes you a more valuable team member.
Think Systems, Not Components
ASHRAE standards work best when considering the interactions between systems. Your envelope design affects HVAC loads. Your HVAC design affects electrical loads. Your lighting design affects cooling loads. Everything connects.
The projects that work best are those where the architect, structural engineer, and MEP team communicate with each other from the beginning. ASHRAE compliance becomes easier when everyone understands how their decisions affect the whole building.
Technology That Makes ASHRAE Compliance Easier
Smart Controls That Work
The HVAC control systems accessible today are impressive compared to those we had just five years ago. AI-driven optimization, predictive maintenance, and integrated monitoring—these are no longer futuristic concepts. They are standard features that make ASHRAE compliance automatic rather than manual.
I recently worked on a project where the building automation system adjusts ventilation based on occupancy sensors, outdoor air quality, and weather forecasts. The system maintains ASHRAE 62.1 compliance while using 25% less energy than a conventional design. More importantly, it does this automatically—no need for constant manual adjustment.
VRF Systems: Flexibility That Pays Off
Variable Refrigerant Flow systems have become very effective at handling diverse thermal zones efficiently. For buildings with mixed-use or variable occupancy, VRF can provide the precise control needed for ASHRAE 55 compliance while often exceeding 90.1 efficiency requirements.
The control flexibility is what sells us on VRF for many projects. Each zone can be controlled independently, allowing you to optimize comfort and efficiency for different space types within the same building.
Heat Recovery: The Technology That Pays for Itself
Energy recovery ventilators and heat recovery systems are becoming no-brainers on most projects. They help you meet ASHRAE 62.1 ventilation requirements while reducing the energy penalty of outdoor air. Payback periods of 3-5 years are common, and the technology is reliable enough that maintenance is not a concern.
Common Pitfalls and How to Avoid Them
Over-Ventilation: More Is Not Always Better
I’ve seen too many projects where the design team thinks more ventilation is always better. It is not. Over-ventilation wastes energy and can create comfort problems by introducing unconditioned air at the wrong times.
The solution is proper controls and monitoring. Provide people with the ventilation they need when they need it, rather than maintaining maximum ventilation at all times.
Ignoring Interactions Between Standards
ASHRAE standards do not exist in isolation. Decisions you make for 90.1 compliance affect 62.1 implementation and conversely. The best approach is an integrated analysis that considers all applicable standards simultaneously.
Forgetting About Long-Term Performance
Systems that comply with ASHRAE standards on day one might not comply five years later without proper maintenance and monitoring. Design systems that can maintain performance over time and ensure owners understand what is required to keep them functioning correctly.
Practical Tools That Help
Software That Doesn’t Drive You Crazy
We rely on Trace 700 for most of our energy modeling projects. It is comprehensive without being overwhelming, and the interface makes sense. For more complex projects, EnergyPlus gives you a more detailed analysis, but the learning curve is steeper.
Carrier HAP is solid and reliable for load calculations. It integrates well with other tools and produces documentation that helps during design development.
Documentation That Works
ComCheck is your friend for ASHRAE 90.1 compliance documentation. It is free and officially produces reports that code officials accept. Do not overthink the documentation—clear, simple, and complete beats fancy and confusing.
What’s Coming Next
Electrification Reality Check
Heat pumps are getting better fast. New refrigerants, improved compressors, and intelligent controls enable heat pumps to meet ASHRAE efficiency requirements even in the most extreme climates. If you’re not already considering electrification, start now.
IAQ Is not Going Away
Enhanced filtration and increased outdoor air are becoming standard expectations, not special requirements. Plan for MERV 13 filters as a baseline and ensure your fan systems can handle the additional pressure drop.
Carbon Accounting
Building performance standards are being developed that will utilize ASHRAE baselines for carbon compliance. Buildings that exceed current ASHRAE requirements will have easier paths to compliance with future carbon regulations.
Making It Work for Your Projects
Here’s our practical advice for architects and contractors dealing with ASHRAE requirements:
Weeks 1-2 of any project: Determine the applicable ASHRAE standards and set performance goals. Do not wait for the MEP engineer to bring this up.
The schematic design phase: Preliminary energy models are developed. They do not have to be perfect, but they need to identify significant issues and opportunities.
Design development: Finalize equipment specifications and compliance strategies. Document everything clearly, and in the future, you will thank yourself.
Construction: Verify that installed equipment matches specifications. Test performance before occupancy. Train operators properly.
The bottom line: ASHRAE standards work when you work with them, not against them. They are tools for creating better buildings, not obstacles to overcome. The projects that get this right deliver better performance, lower operating costs, and happier occupants.
After 15 years of working in this field, we are convinced that ASHRAE compliance is one of the best investments you can make in a building’s long-term success. The standards might seem complex, but they represent decades of collective wisdom about what works in real buildings with real people.
The question is not whether to comply with ASHRAE standards—it is how to use them to create buildings that perform better than anyone expected.