For contractors hiring technicians into their own shop, not for homeowners looking for one.
Every one of these pages exists because of the same gap. You have a resume, a credential, and forty-five minutes, and none of the three tells you whether the person in front of you can diagnose a system they have not seen before. The credential says they are eligible. The resume says where they have been. The interview measures how well they talk about their work, which correlates with skill and correlates harder with confidence.
The guides below cover what to do about that, one trade at a time. All of them are free and none of them asks for an email address.
Three questions, three kinds of page
| Guide | What it covers | Use it when |
|---|---|---|
| Skills test | What to measure, how contractors evaluate technicians today and where each method breaks down, and how to weight the test by role | You have more applicants than you can ride along with and need to compare them on one scale |
| Interview questions | Questions by area, each with why you are asking, what a strong answer contains, and what a memorized one sounds like | You have the interview booked and want it to produce a signal rather than a formality |
| Credential verification | What the credential legally establishes, how to actually confirm it, and what it still does not tell you | A candidate has handed you a card or a license number and you want to know what it is worth |
Scroll sideways to see all three columns.
They are steps in a sequence rather than alternatives. A typical run is a phone screen, then a skills assessment, then an interview built around what that assessment surfaced, with the credential check somewhere before the offer.
HVAC
An EPA 608 card is a legal requirement, not a measure of ability: it never expires, and a technician who earned one in 2009 has demonstrated nothing about their diagnostic ability today. HVAC skills test covers what to measure instead, HVAC interview questions covers the conversation, and How to verify an EPA 608 certification covers the card itself, which has no national registry to search.
- HVAC skills test
- How to verify an EPA 608 certification
- HVAC interview questions
- Free HVAC interview scorecard
Electrical
An electrical license is a stronger credential than most in the trades, and it still does not tell you which kind of electrician you are getting. A journeyman with eight years of new construction rough-in and one with eight years of residential service hold the same license and do different jobs. Electrician skills assessment and Electrician interview questions are both built around finding out which one is sitting across from you.
Plumbing
Plumbing is the trade where the gap between a resume and reality is widest, because service, drain, new construction, and commercial are genuinely different jobs that all carry the same title. Plumber skills test and Plumber interview questions are weighted to tell those disciplines apart, which matters more here than in any other trade.
Score every applicant on the same scale.
TradeGrader sends candidates a role-specific assessment for their trade and returns a report you can compare across applicants. Free trial, no card required.
Start Free TrialWhat the alternative costs
Most contractors evaluate by hiring and finding out, and it is the most expensive option rather than the cheapest. The cost is not just the wage: it is the callbacks, the senior technician's diverted hours, the customer who does not book again, and the recruiting spend you get to repeat. The bad hire cost calculator turns your own numbers into that figure, itemized, with the formula and source behind every line.