Lancaster County Wet Basement Guide (2026)

Updated October 29, 2026. General information only, not legal, engineering or geological advice. Rules and programs change, so confirm with the agency named before work starts.

Quick reference

Topic	What to know	Source
Contractor registration	Home improvement contractors register with the PA Attorney General; exemption below $5,000 in prior-year home improvement work	PA Attorney General
Contract	Written and signed for jobs over $500, with total price, start and end dates, description of work and a right-to-cancel notice	PA Attorney General
Right to cancel	Three days, using the notice wording the law specifies	PA Attorney General
Before digging	Dial 811 (PA One Call) at least three business days ahead; applies to homeowners	PA Public Utility Commission
Precipitation	About 44 inches a year; about 21 inches of snow (1991 to 2020 normals)	NOAA, via Wikipedia
Radon	About 40% of PA homes tested exceed 4 pCi/L	PA DEP
Indoor humidity	Below 60%, ideally 30% to 50%	U.S. EPA

What is under Lancaster County basements?

Much of the county's best-known farmland sits on soils that weathered out of limestone. The USDA's official description of the Hagerstown series notes that the series was established in Lancaster County, formed in residuum of hard gray limestone, and has a surface of silt loam or similar over a subsoil of silty clay, clay or silty clay loam, with hard limestone typically 40 to 84 inches or more down. It is classed as well drained with moderate permeability, but that clay-rich subsoil still slows water as it moves past a foundation, which is one reason basement walls stay wet for days after a soaking rain.

Below the soil, the limestone and dolomite dissolve slowly. A Pennsylvania guide on sinkholes explains that rainwater and soil gas form a weak carbonic acid that widens fractures in carbonate rock into underground drains, and that moving water is the main trigger for flushing soil into those drains. The Pennsylvania Geological Survey's report Sinkholes and Karst-Related Features of Lancaster County (W. E. Kochanov, 1990) maps sinkholes, surface depressions and caves across the county on 18 maps at 1:24,000 scale.

Why does that matter for waterproofing?

Because every waterproofing system moves water somewhere. Gutters, footing drains, interior drains and sump pumps all collect water from a wide area and release it at one outlet. The state's guidance names concentrated stormwater and leaking pipes as common sinkhole triggers, and Warwick Township tells residents that redirecting downspout runoff may be needed to stop a sinkhole from growing. A sensible plan in Lancaster County spreads discharge water over ground that slopes away, keeps it off the foundation, and avoids sending it all into one low spot year after year.

Warning signs listed in the state's sinkhole guidance include new cracks in walls or floors, sagging porches, doors that start to stick, depressions in the yard and leaning trees. If a hole opens up, keep people away from it, don't go into it, and call the gas company right away if a gas line could be involved. The same guidance suggests checking whether your homeowner's policy covers sinkholes and talking with your municipality about the bedrock under your property.

How old are the foundations?

Some of them are very old. The Hans Herr House in West Lampeter Township, built in 1719 of sandstone, is described as the oldest dwelling in Lancaster County, and the Johannes Harnish Farmstead nearby includes a stone farmhouse from 1774 and a late-18th-century stone springhouse. Lancaster city was laid out in 1734. Stone and brick cellars laid in lime mortar are common in the city, the boroughs and on farms, and they call for different repairs than poured concrete. See our stone foundation repair page.

What does Pennsylvania law say about the contract?

Pennsylvania's Home Improvement Consumer Protection Act applies when the total price of the work is more than $500. According to the Attorney General's office:

Contractors who do home improvement work in the state must register with the Attorney General and renew every two years, unless their home improvement work totaled less than $5,000 in the previous tax year. Out-of-state contractors working in Pennsylvania must comply too.
The contract must be in writing, signed by both you and the contractor, and include the total price, estimated start and completion dates, a description of the work and a notice of your right to cancel.
You have three days to cancel, and the notice has to use the wording the law specifies. If it doesn't, the contract may be voidable even after the three days pass.
For projects over $5,000, the law limits the down payment; the Attorney General points to one-third of the contract price, plus the cost of special-order materials.

You can look up a contractor's registration on the Attorney General's home improvement contractor site before you sign.

Do I need a permit?

Pennsylvania municipalities enforce the Uniform Construction Code. In Lancaster city, the Bureau of Building Code Administration reviews plans and issues residential building permits, and the Historical Architectural Review Board reviews exterior alterations in the Historic District. Outside the city, ask your township or borough, which may use its own staff or a third-party inspection agency. The contract should say whether a permit is needed and who will obtain it.

What about digging and discharge?

Exterior waterproofing and buried discharge lines mean digging near utilities. The Pennsylvania Public Utility Commission says homeowners and contractors must call 811 at least three business days before excavation. In Lancaster city, keep pump water out of the sewer: the city's combined sewer system carries sewage and stormwater together and can overflow into the Conestoga River in heavy rain, and the city is updating its overflow control plan under a 2018 consent decree with the U.S. EPA and Pennsylvania DEP.

What about radon and indoor air?

Pennsylvania DEP says about 40 percent of homes tested in the state have radon above the EPA action level of 4 pCi/L and recommends testing in the basement. The U.S. EPA recommends keeping indoor humidity below 60 percent, ideally 30 to 50 percent, and drying water-damaged materials within one to two days. Both are worth checking when you're already working on a basement.

What does waterproofing usually cost here?

We don't publish price ranges because we couldn't find a reliable local source for them, and the spread between a single crack and a full stone-cellar drainage job is enormous. Ask for a written, itemized proposal that separates drainage, pump, masonry and restoration work so you can compare companies line by line.

Questions to ask a waterproofing company

What is your Pennsylvania home improvement contractor registration number?
Where exactly is the water getting in, and how does your plan address that spot?
If my walls are stone, what mortar or coating will you use and why?
Where will drain and pump water discharge, and how will you keep it from concentrating in one spot?
Does the job need a permit, and who will get it?
How much is the deposit, and what does the payment schedule look like?
What does your written warranty cover, and does it transfer if I sell?

Common questions

Are sinkholes common in Lancaster County?

Yes, in areas over limestone and dolomite. The Pennsylvania Geological Survey has mapped sinkholes and karst features across the county, and Warwick Township says sinkholes are common where there is limestone soil.

How long do I have to cancel a home improvement contract in Pennsylvania?

Three days, under the Home Improvement Consumer Protection Act. The contract must include a cancellation notice worded the way the law requires.

Do I have to call 811 before digging in Pennsylvania?

Yes. The Pennsylvania Public Utility Commission says homeowners and contractors must contact PA One Call at least three business days before excavating.

Lancaster County, PA wet basement guide (2026)