A.J. Waterproofing, LLC

4.5 | 12 Verified Ratings
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3774 Kratz Road
Collegeville, PA 19426
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A.J. Waterproofing, LLC

We a family run waterproofing specialist company that has been owned and operated since 1976 by A.J. DiElsi. We have one crew, one truck and start and finish one job at a time. We are completely insured with general liability and workman's compensation. There is no charge for estimates and we take no deposits on any job. You pay us upon completion of the job. We do not have salesmen. A.J. is the gentleman that comes out to give each estimate and he is on each job. We do impeccable workmanship, and the jobs are always left cleaner than when we arrived. We give a lifetime guarantee on our French Drains and it is transferable to new homeowner. Please feel free to call with any questions 610-409-0888.


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Service Area

  • Philadelphia
  • Norristown
  • Valley Forge
  • Wayne
  • North Wales
  • Media
  • Eagleville
  • Harleysville
  • West Chester
  • Warminster
  • Spring House
  • Telford
  • Southeastern
  • Springfield
  • Conshohocken
  • Phoenixville
  • Doylestown
  • Collegeville
  • Exton
  • Pottstown
  • Audubon
  • Blue Bell
  • Warrington
  • Glenmoore
  • Dublin
  • Berwyn
  • Oaks
  • Bala Cynwyd
  • Flourtown
  • Gladwyne
  • Wynnewood
  • Bridgeport
  • Boyertown
  • Souderton
  • Chalfont
  • Wyncote
  • Narberth
  • Colmar
  • West Point
  • Villanova
  • Paoli
  • Schwenksville
  • Worcester
  • Broomall
  • Hatfield
  • Dresher
  • Cheltenham
  • Oreland
  • Merion Station
  • Skippack
  • Glenside
  • Elkins Park
  • Fairview Village
  • East Greenville
  • Bryn Mawr
  • Chester Springs
  • Sellersville
  • Spring City
  • Franconia
  • Jenkintown
  • Devon
  • Malvern
  • Fort Washington
  • Hilltown
  • Gwynedd Valley
  • Jamison
  • Lansdale
  • Hatboro
  • Havertown
  • Newtown Square
  • Gilbertsville
  • Clifton Heights
  • Horsham
  • Lansdowne
  • Elverson
  • Pennsburg
  • Abington
  • Quakertown
  • Haverford
  • Downingtown
  • King of Prussia
  • Royersford
  • Upper Darby
  • Silverdale
  • Lafayette Hill
  • Perkiomenville
  • Perkasie
  • Ambler
  • Douglassville
  • Plymouth Meeting
  • Fountainville
  • Montgomeryville
  • Ardmore
  • Salfordville
  • Drexel Hill
  • Willow Grove
  • See All >

Services Offered

  • Waterproofing Foundation or Basement

Areas of Expertise

  • Waterproofing

Quick Facts

Business Hours
(Please call to confirm)
  • Commercial
  • Free Estimates
  • Residential


In Business Since: 1976
State Licensing
Trade: Home Improvement Contractor
License #: PA054659
Expiration: 02-05-2022
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Ratings & Reviews
A.J. Waterproofing, LLC

Real feedback from real homeowners.
Learn more about this pro by reading the ratings and reviews below.
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Showing 1-10 of 12
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5.0   |  
Review by in Mohnton, PA
Project: Waterproof Inspection / Certification Service
We recently had work done by AJ Waterproofing and cannot say enough about their work. From the minute they arrived, AJ was like a maestro conducting his very capable crew to establish a containment area to prevent dust and debri from permeating the rest of the house. Every effort was made to cover furniture, speakers and carpet with plastic. From there, it only got better. AJ and crew made short work of jack hammering the floor, tunneling under the existing paneled wall without disturbing the paneling and trim. This alone saved me a few thousand dollars on repair and replacement. His crew continuously swept and discarded debri to ensure a clean work area.. Without even asking, his guys installed the drains for our furnace condensation line, softener and dehumidifier within the french drain system. The coup de gras was a meticulous cleanup, which included wiping down the floor and walls, making it cleaner than when he started! I highly recommend AJ for all your waterproofing needs. A true pro.
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5.0   |  
We recently used AJ's Waterproofing Services to fix our water issues in our basement and we couldn't be happier with the job him and his team did. It was very apparent from our consultation with him that he is the ultimate professional. He spent over an hour and a half with us explaining the issues at hand in our basement and the different options we could go with to remedy the situation. It never once felt like he was out to oversell us or take advantage of us. We knew very quickly he was the man for our job. The day of the French drain install, he sent us multiple updates throughout the day. After they were done for the day, they thoroughly cleaned the area. There were no traces of dust and debris from where they dug up the concrete. We just had a major rain storm and we had no water in the basement. I would highly recommend AJ's Waterproofing for all of your water issue needs.
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0.5   |  07-19-2019
These guys have no idea what they are doing. I hired them to remedy two leaking window wells. Both leaked in less than one year. He sent his son to fix one, the other one still leaks. I sent him photos and he had the nerve to ask me who put the PVC pipe so close to the foundation? Ummm, you guys did? This is your botched job. They should stick to boarding horses because waterproofing basements clearly is not what they are good at. Avoid this company.
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5.0   |  
Review by in Royersford, PA
Great service, professional, knowledgeable, affordable and fast and tidy. A crew came out on a holiday and took care of my issue post haste. Would definitely hire again.
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4.33   |  
Review by in Aldan Pa, PA
They were very professional and efficient!
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5.0   |  
Review by in Hatboro, PA
Quick service. Provided multiple options that would fit my budget.
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5.0   |  
Review by in Pottstown, PA
Water / dampness in basement - 1st appt with AJ was a walk thru and he shared recommendations on options he could or i can try to remediate. AJ checked in with us a week later to see how we made out. Our attempts minimally helped, but did not fix. AJ was aware of time constraints, team came in, hustled and completed in one day. super impressed with quality of work, professionalism and cleanup.
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5.0   |  
You're lucky if you get them.
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5.0   |  
AJ Waterproofing is a thoroughly professional waterproofing business. Clean, fast, top quality workmanship and friendly! I would definitely recommend them to anyone who is in need of water alleviation in their basement! Do it correctly the first time - hire AJ Waterproofing!
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4.0   |  
AJ didn't try to oversell me on unnecessary work proposed by other contractors. He removed a truckload of stuff from the basement room with the water problem at no extra cost. When they finished installing the interior & exterior drains and cleaned the floor the room was cleaner than when they started. After one rain there was some water on the floor but it dried before AJ could come out. We haven't had a heavy rainfall since to really test the system, but I'll increase the rating to 5 stars when it's had more of a test.
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Showing 1-10 of 12
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