- What CRD Means in Geothermal Design
- The Issuer and the Legacy Status
- What a Certified Residential Geothermal Designer Does
- The Nine Preparation Topic Areas
- What We Know (and Don't) About the Exam
- Renewal Mechanics for Active Holders
- CRD vs. the GRSD Transition Path
- Who Uses This Credential
- Sequencing Your Preparation by Topic
- Frequently Asked Questions
- CRD here means Certified Residential Geothermal Designer, issued by the International Ground Source Heat Pump Association (IGSHPA).
- CRD is now a legacy credential; IGSHPA offers legacy courses only case by case when a utility, state or provincial program requires them.
- Active holders can renew indefinitely with continuing education; lapsed legacy credentials cannot be reinstated.
- Renewal costs USD $75 per year for members or $225 per year for non-members, in one-, two- or three-year terms.
What CRD Means in Geothermal Design
Several unrelated credentials share the acronym "CRD," so precision matters. On this page, CRD means the Certified Residential Geothermal Designer credential from the International Ground Source Heat Pump Association (IGSHPA). It is a designation for people who size and lay out ground source heat pump (GSHP) systems for houses and other small residential-scale buildings. It is not related to any other certification that happens to abbreviate the same way.
If you landed here searching for a quick definition, our shorter explainers cover the basics: what CRD stands for, the CRD meaning, and what CRD is. This article goes deeper into how the credential works, where it stands today, and what it asks of the people who hold or pursue it.
The Issuer and the Legacy Status
IGSHPA documents the CRD identity explicitly in its white paper on sunsetting legacy training courses and certifications (White Paper 251229, revision 260114, dated January 14, 2026). That paper reports that normal legacy training was to be replaced by the end of 2025. Understanding what that sentence does and does not mean is the single most important thing a prospective candidate can do before spending money or time.
That framing shapes how we write about CRD. We do not advertise unrestricted enrollment, because it does not exist in the form it once did. What does exist is a population of active holders who maintain the credential, a set of historical preparation topics that remain sound design fundamentals, and a clearly defined transition route for people who want a current IGSHPA designation. For eligibility questions, see our guide to CRD requirements.
What a Certified Residential Geothermal Designer Does
A residential geothermal designer translates a building's heating and cooling needs into a ground loop and heat pump specification that will perform for decades. The work sits between the load calculation and the installation crew. A designer must decide how much heat the home loses and gains, which heat pump configuration fits, how much loop is required, how the site and soil will behave, and whether the economics justify the system.
The credential signals that a person has been trained in that chain of decisions rather than only in installation technique. That distinction is why utilities and state or provincial incentive programs have historically referenced designer certification when they set program requirements. If you are weighing career angles, our overview of CRD jobs and the CRD salary guide discuss the employment side qualitatively.
The Nine Preparation Topic Areas
IGSHPA's historical event listing for the CRD course, delivered online with HRAI, laid out nine preparation topics. They are unweighted headings drawn from that listing. They are not a current weighted examination blueprint, and they do not prove exhaustive exam coverage, so do not infer a "most heavily tested" domain from them. They do, however, map the knowledge a residential designer genuinely needs. For a fuller walkthrough, see our CRD exam domains guide.
Domain 1: Ground Source Heat Pump Benefits
The case for GSHP technology versus conventional equipment, framed for homeowners and decision-makers.
- Efficiency and operating-cost advantages of using the ground as a heat source and sink
- Comfort, equipment longevity and environmental arguments
- Being able to explain benefits accurately without overpromising
Domain 2: System Components
The physical pieces of a GSHP system and how they interact.
- Heat pump unit, ground loop piping, circulating pumps and fluid
- Distribution equipment inside the home
- How component choices influence reliability and serviceability
Domain 3: Heat Pump Types
Distinguishing the main configurations and what each implies for design.
- Water-to-air versus water-to-water equipment and their typical applications
- Open-loop versus closed-loop arrangements at a conceptual level
- Matching heat pump type to the distribution system and the building
Domain 4: Design Process
The sequence a designer follows from first site visit to final specification.
- Gathering building, site and owner information
- Sequencing load, equipment and loop decisions in the right order
- Documenting assumptions so the design can be checked and defended
Domain 5: Energy Requirements
Understanding how much energy the home uses and how the heat pump meets it.
- Annual heating and cooling energy versus peak demand
- Relating building characteristics to system energy use
- Why balanced heating and cooling influences the ground
Domain 6: Load Calculations
The foundation of every sound design: how much heating and cooling the building actually needs.
- Envelope, infiltration, ventilation and internal gain inputs
- Consequences of oversizing and undersizing equipment
- Producing numbers you can trace back to documented inputs
Domain 7: Parameters That Affect Heat Pump Performance, Site, Geology and Soil Conditions
How the site and the ground change what the system can deliver.
- Soil and rock thermal behavior and moisture influences
- Site constraints that limit loop options
- Operating conditions that change heat pump performance across seasons
Domain 8: Heat Pump and Pipe Design
Turning loads and site data into specified equipment and a loop that moves the needed energy.
- Selecting heat pump capacity against the calculated loads
- Pipe sizing, flow and pressure considerations
- Loop sizing logic tied to ground conditions
Domain 9: Economics of Design
Evaluating whether a design makes financial sense for the owner.
- Installed cost versus operating savings over time
- How design choices shift the cost and payback picture
- Presenting economics honestly, including uncertainty
What We Know (and Don't) About the Exam
IGSHPA's listing ties certification to passing the corresponding examination. Beyond that, we have not verified a current legacy-exam question count, time limit, passing mark or initial exam fee, and we will not guess at them. That is why you will not find invented numbers here. If you are researching difficulty or scoring, read our pages on how hard the CRD exam is, the CRD passing score and the CRD pass rate with that limitation in mind.
What you can say with confidence is that the content is applied rather than purely theoretical. The nine topic areas above revolve around calculation, selection and judgment: sizing loads, matching equipment, laying out piping and evaluating site conditions. Preparation therefore rewards working through realistic residential scenarios over memorizing isolated definitions.
Renewal Mechanics for Active Holders
For people who already hold the credential, the practical question is not "how do I take the exam" but "how do I keep what I have." IGSHPA's renewal policy (fee policy effective January 1, 2024) governs this, and the key facts are concrete.
| Renewal Item | Detail |
|---|---|
| Term options | One, two or three years |
| Member rate | USD $75 per year |
| Non-member rate | USD $225 per year |
| Continuing education | CEU documentation required for processing; IGSHPA describes eight CEU points per three-year cycle (points, not classroom hours) |
| Membership requirement | The membership term must cover the discounted certification-renewal term |
| Individual membership | USD $125 per year for currently employed professionals |
| Lapsed credentials | Cannot be reinstated, per the current FAQ |
These are renewal charges, not initial exam fees. Our CRD certification cost breakdown separates what is verified from what is not. A few practical notes follow from the table:
- Do the membership math. The member renewal rate is lower than the non-member rate, but you must hold membership that covers the discounted renewal term. If an eligible business, community or utility membership already covers you, a separate individual membership is unnecessary.
- Document CEUs as you earn them. Because documentation is required for processing, collect certificates and records throughout the cycle instead of reconstructing them at the deadline.
- Do not let it lapse. Because lapsed legacy credentials cannot be reinstated, a missed renewal is effectively permanent. Active holders may continue renewing indefinitely, so the credential's value rests on continuity.
Key Takeaway
For an active CRD holder, calendar discipline is worth more than any study technique. Set a renewal reminder well ahead of expiration, confirm your membership term covers the renewal term, and keep CEU records organized in one place.
CRD vs. the GRSD Transition Path
IGSHPA's white paper treats the GRSD examination as a separate, optional upgrade path. Taking it is not an automatic renaming or replacement of CRD. The two should be kept distinct in your planning.
| Question | CRD (Legacy) | GRSD Path |
|---|---|---|
| Status | Legacy credential; renewable by active holders | Separate examination, optional upgrade |
| New candidates | Verification hold; case-by-case legacy offerings tied to program requirements | Confirm current details directly with IGSHPA |
| Relationship | Not automatically renamed or replaced | Not an automatic conversion of CRD |
| Fees, timers, validity | Renewal fees verified; initial exam details not verified | Do not assume CRD figures apply |
If you hold CRD and wonder whether the upgrade is worthwhile, that is a business judgment about your market, your program requirements and your employer. Our analysis in is the CRD certification worth it frames the decision, and the plain-language overview at CRD certification covers the fundamentals.
Who Uses This Credential
The people who carry or look for this designation tend to fall into a few groups. Residential HVAC and geothermal contractors use it to show design competence on their own projects. Design-focused staff at installation firms use it to separate themselves from crews that only install. Utility and state or provincial program administrators have historically referenced IGSHPA designations when setting contractor or designer requirements, which is precisely why legacy courses remain available when a program calls for them.
Because incentive and program rules vary by jurisdiction, the credential's practical weight depends on where you work. Check the specific program you intend to serve before assuming a CRD is required, accepted or superseded.
Sequencing Your Preparation by Topic
If you are working through the historical CRD curriculum, whether for a program-required legacy offering or to build design fluency, order matters because the topics build on each other. Load calculations feed equipment selection, which feeds loop design, which feeds economics. A sequence that mirrors the design process keeps the material coherent. For a fuller plan, see the CRD study guide, and keep the CRD cheat sheet handy for quick review.
Orientation: Benefits, Components, Heat Pump Types
- Cover Domains 1 to 3 so the vocabulary is solid before any calculation
- Sketch a labeled diagram of a complete residential system from memory
Design Process and Energy Requirements
- Study Domains 4 and 5 and write out the design sequence in your own words
- Distinguish peak demand from annual energy use
Load Calculations
- Spend the most time on Domain 6; every later decision depends on it
- Work several full residential examples and check that inputs trace to your assumptions
Site Conditions and Heat Pump and Pipe Design
- Combine Domains 7 and 8 so ground behavior informs loop sizing
- Practice moving from a calculated load to a specified equipment and piping layout
Economics and Integrated Review
- Cover Domain 9, then run end-to-end design scenarios across all nine areas
- Use timed practice questions to find weak topics
The reasoning is simple: front-load vocabulary, put the heaviest calculation work in the middle when your focus is fresh, and finish by tying economics back to the design you built. Note that this sequence reflects the design workflow, not exam weighting, which is unverified. When you are ready to test yourself, our practice test site offers scenario-based questions, and the CRD exam dates page explains why scheduling depends on a verified legacy offering.
Frequently Asked Questions
It stands for Certified Residential Geothermal Designer, a credential from the International Ground Source Heat Pump Association (IGSHPA). It is unrelated to other credentials that share the acronym. See our explainer on what CRD certification is for more.
Enrollment is under a verification hold. IGSHPA says legacy courses are considered case by case and offered only when a utility, state or provincial program requires them. Confirm a specific current offering with IGSHPA before planning around it.
Current renewal products offer one-, two- or three-year terms at USD $75 per year for members and USD $225 per year for non-members. CEU documentation is required, and the membership term must cover the discounted renewal term. These are renewal charges, not initial exam fees.
IGSHPA's current FAQ says lapsed legacy credentials cannot be reinstated. Active holders may renew indefinitely with required continuing education, so staying current is essential.
No. The GRSD examination is a separate, optional upgrade path, not an automatic renaming or replacement of CRD. Its objectives, fees and rules are its own and should not be assumed to match CRD.
Whether you hold the credential, are weighing a program-required legacy course, or are building design skills from the historical curriculum, the core discipline is the same: understand the loads, respect the ground, and document every assumption. Start with the nine topic areas, confirm current availability and renewal terms directly with IGSHPA, and use targeted practice to turn the material into reliable design judgment.