Exterior Waterproofing for New and Old Basements and Foundations

Waterproofing basements and foundations almost always starts on the exterior of the wall.  Why? because the postive water pressure pushes any waterproofing material into the concrete and it doesn't have any place to go.  If we applied the same waterproofing materials on the inside of the foundation, water would move through the porous concrete and push the coatings off.  While drain tile systems under the basement floor might be useful, they are not waterproofing since your allowing the water inside and pumping it out, we call drain-tile sytems "water-management."  The most innovative waterproofing techniques are constantly being developed for exterior waterproofing



What's the Difference in Exterior Waterproofing and Dampproofing

Poured Basement Wall with Exposed Foundation Ties

On the inside, water is moving through the wall at the exposed foundation tie, there's also a vertical basement wall crack allowing a lot of water into the wet basement.  The black plastic is part of a drain-tile system but there's too much water so it flows over the plastic onto the floor.

Outside we see a different foundation tie, higher up on the basement. These metal bars average 1/4" x 1.5" and go from floor to ceiling about every 36."  When foundation ties are exposed to water they will start rusting like this one. 

Foundation ties also introduce stress points in the concrete and it's very common to see inside cracks starting at one of these, like we see in the previous photo, this will also let in a lot of basement water.

New Construction Using CETCO Bentonite Panels on Exterior Foundation Walls

This is old school bentonite waterproofing from CETCO, one of our suppliers.  Several years ago we'd buy these cardboard panels that had bentonite powder in the middle.  If water got through the outside the bentonite would swell and protect the building's foundation from water.  Bentonite for new construction is now available in rolls with a plastic barrier and different version that protect walls or under the basement floor.

CETCO improves bentonite exterior waterproofing every year.  There's a great article in Waterproofing Magazine talking about some of the new products for exterior waterproofing applications. https://www.waterproofmag.com/2015/04/active-hybrid-waterproofing-technologies/

See the black spots above the Ultraseal Membrane, it's CETCO Bentoseal, a real nasty material that's like axel grease.  This is smeared on the foundation walls where any imperfections are noticed in the basement wall and over the exposed foundation ties before the membrane is attached and the area backfilled.  This material is considered Real Waterproofing, it will stop water intrusion outside of the foundation.

Here's the Kuder on one of Great Lakes Waterproofing's Job Sites doing exterior basement waterproofing for new construction.  This underground storage bunker could not have any water going through the walls so the owner went with bentonite for Real Waterproofing!  Bentoseal is smeared on any imperfections like foundation ties and porous areas the concrete didn't fully fill.  Bentoseal is also smeared on the footing/wall junction and then a CETCO Hydrobar Tube (the small tubes sitting on the footing) are also placed in this area.  The wrapper holding the bentonite will "melt" when in contact with water activating the bentonite.  Many more steps include pinning the membrane to the wall and overlapping everything to insure this foundation stays dry forever.

Exterior Waterproofing for Apartment Buildings

Great Lakes Waterproofing loves waterproofing existing apartment buildings.  In almost all wet apartment situations, we do the waterproofing on the exterior so there's no need to move the tenant.  Our waterproofing process goes quick with very little disruption to the neighbors.

Most of the wet apartments we work on are garden level so the depth is usually around 4'-6'.  Exterior bentonite injections fills the voids and water pathways outside of the building, stopping the water for Real Waterproofing!

Waterproofing old Stone or Rubble Basement Wall

This wet elevator pit in Saint Paul needed waterproofing.  For Real Waterproofing from Great Lakes Waterproofing we pumped a slurry of bentonite either through the walls or outside around the perimeter of this elevator pit.  Bentonite is perfect for waterproofing old stone and rock foundation walls, it fills in the nooks, crannies and voids outside water is using as a pathway to get into your wet basement.

Other companies put up plastic sheets leading down to a collection system which allows the water to keep flowing and mold and mildew keep growing.  Before you consider any inside plastic wall panels for basement waterproofing, call Great Lakes Waterproofing for exterior waterproofing, stopping the water outside!

Bentonite Exterior Waterproofing for Old Stone Walls

It looks like Great Lakes Waterproofing has made a mess in this 150 year old wet basement but we call it "finding the sweet spot" one of the many holes in this basement wall leaking water.  The bentonite will thicken up and cork up this hole, a concrete patch will be applied on the inside of the basement wall and the homeowner can enjoy their walls without a silly plastic wall barrier put up.