The word "waterproofing" on an estimate doesn't decide anything. The permits follow what the crew will actually do.
Match each piece of the job to its permit
Ask the contractor for a written scope that lists each of these separately, then check it against L&I's rules:
- Wall coatings, sealers, paint. L&I's Building Permit page lists painting and similar wall finishes, and repairs that are regular maintenance, among work that often needs no permit, as long as the property isn't on the Philadelphia Historic Registry.
- Cutting the floor, digging a sump pit or a perimeter trench. Building Permit, because it's basement excavation. L&I's FAQ makes the same point about contractors digging out a basement floor to gain ceiling height.
- New sump basin piping, check valve and discharge line. Plumbing Permit. L&I's rule covers installation, alteration, replacement and repair, and a licensed master plumber has to oversee the work.
- A new receptacle or circuit for the pump. Electrical Permit, done by a licensed electrical contractor, with a licensed third-party electrical inspection agency hired to inspect it. See our guide to Philadelphia electrical permits.
- Plugging a pump into an existing approved outlet. L&I's electrical page lists connecting approved portable equipment to an existing approved receptacle as work that may not need an Electrical Permit. That covers the plug, not the pit or the piping.
Replacing just the pump is the gray area
L&I's plumbing exemptions are narrow: minor repairs with the same material, such as replacing faucets, valves and parts, plus stopping leaks and clearing stoppages. The page doesn't name sump pumps. If a plumber says a straight pump swap in an existing pit needs no permit, ask which exemption they're relying on and get that in writing, or ask L&I through 311 before the work starts. Our guide to which plumbing jobs need an L&I permit covers the general rules.
Rowhome digging needs more care
Excavation deeper than 5 feet below adjacent grade has to be added to the building permit as a combination permit or covered by a separate Excavation Site Permit. If that deep digging is within 10 feet of a neighbor's building, L&I requires Protection of Property documents, including a pre-construction survey, a monitoring plan and the adjacent owner's acknowledgement. Neighbors must get written notice of excavation below a party wall, and underpinning needs a licensed special inspections engineer on site the whole time. If a proposal includes lowering the basement floor or underpinning, treat it as a structural project and ask whether a structural engineer has designed it.
Know which water you're fighting
A sump pump handles groundwater that seeps through walls and floors. It doesn't stop sewage coming up through a floor drain. The City's Guide to Flooding in Philadelphia treats those as separate problems:
- Water at the wall-floor joint or through cracks after long rain points to groundwater. The guide's fixes are sealing cracks, a sump pump, and grading soil away from the house.
- Dirty water rising from a floor drain, toilet or sink during heavy storms points to a sewer backup. The fix there is a backwater valve or drain plug, not a pump. The guide says to call the Philadelphia Water Department at 215-685-6300 to schedule an inspection before pumping that water out.
- You may qualify for a free backwater valve through PWD's Basement Protection Program (215-685-6069). If you install one on your own, the guide says to hire a licensed plumber who can get the L&I permit.
One more permit trigger from the same guide: since the City's 2019 Plumbing Code, adding any new plumbing fixture below your fresh air inlet requires a backwater valve. That matters if the waterproofing job is the first step toward a basement bathroom or laundry. For where the pump's discharge should go, see our sump discharge guide.
Questions to ask before you sign
- Which permits will you pull, under whose license, and will they be issued before work starts?
- Does the job include cutting the slab or digging, and how deep?
- Where will the discharge line end, and is that location part of the plumbing permit?
- Who schedules the inspections, and will I get the final approvals?
Applications go through L&I's eCLIPSE system online or by appointment at the Permit and License Center in the Municipal Services Building, 1401 John F. Kennedy Blvd. L&I says most plumbing applications without plans are processed within 5 business days and those with plans within 20, plus a day of pre-processing. To confirm a permit was actually issued, search your address in the City's Atlas tool or the L&I Property History lookup, or follow our steps for tracking a Philadelphia permit. City pages were checked November 3, 2026.