When you start watching permit data, the first thing that hits you is how many types there are. A typical city files dozens of permit categories every day — building, electrical, plumbing, mechanical, demolition, roofing, solar, sign, fence, ADU. Most of them aren't relevant to you. The trick is knowing which two or three to actually watch.
Here's the breakdown by what the permit means for your business.
Commercial vs. residential — pick one to start
Commercial and residential permits live in mostly separate worlds. Different licensing, different scale, different sales cycles.
Commercial permits trend large: $500K to $50M, six- to eighteen-month projects, and a GC who probably has a preferred-sub list two years deep. Tenant improvements (TIs) are the exception — those are smaller buildouts when a new business moves in, often $50K-$500K, fast turnaround, and the GC may be hunting for subs in real time.
Residential permits are most of what you'll see by volume. Single-family, additions, ADUs, kitchen and bath remodels. Smaller jobs, faster decisions, more direct access to the homeowner — especially when no contractor is listed on the filing.
If you're a one- or two-truck operation, the residential firehose is where you start. Commercial TIs are the sweet spot for slightly bigger shops with relationships.
The specialty permits matter most
Most cities require a separate permit for trade-specific work. These are the ones to watch if you do that trade — they're a near-pure signal.
- Electrical — panel upgrades, service changes, EV chargers, solar interconnections. A panel upgrade often signals a bigger project (solar, ADU, addition) coming behind it.
- Plumbing — water heater replacements, repipes, sewer laterals. Re-pipes in older neighborhoods come in waves.
- Mechanical / HVAC — equipment replacements, new ductwork. These spike seasonally — heat waves and cold snaps both push them.
- Roofing — re-roofs, repairs, structural. Storm-damage clusters after a hailstorm are the gold rush of the trade.
- Demolition — almost always a leading indicator of new construction filed within 60-90 days. If you're a foundation or framing sub, demo permits are your prospect list.
A few fields tell you most of what you need
You don't need to read every column on a permit. The fields that actually predict opportunity:
| Field | Why it matters |
|---|---|
| Permit type | Filters out the 95% you don't care about. |
| Valuation | Ballpark project size. $5K vs. $500K is a totally different conversation. |
| Applicant | If it's the homeowner, no contractor is locked in yet. |
| Contractor | If it's a competitor, you're probably too late. If it's blank, you're not. |
| Status | "Filed" is earlier than "Issued." Earlier = more time to get in. |
What to ignore
Don't waste time on these unless you have a specific angle:
- Sign permits — almost always the property owner replacing branding. Not a construction lead.
- Fence permits — residential fence work is too small and too DIY-friendly to monetize through alerts.
- Re-roof permits under $3K — usually patch jobs, not full replacements.
- "Repair" permits with no description — too vague to act on.
A couple of habits that pay off
Once you know which permit types to watch, two patterns are worth building into your week:
- Check repeat applicants. Developers, property managers, and a handful of GCs file dozens of permits a year. If you build a relationship with one productive applicant, that's worth more than a hundred cold doorknocks.
- Watch the seasonality. HVAC peaks in July and January. Roofing peaks after the first storm of the season. Demo and grading peak in late spring. Pricing your outreach to the cycle beats fighting it.
Where to find this data
Cities publish permits through different platforms — Socrata (San Francisco, Austin, Chicago, LA), ArcGIS (Columbus, DC), CKAN (Boston, Pittsburgh), and a few custom portals. You can pull from each one yourself, or The Permit Sheet does it for 15+ cities and emails you only the permit types you care about.
Set up a free alert for one permit type in one city — no credit card. See what shows up in your feed for a week. You'll know within a few permits whether it's the right filter for your trade.