Wednesday, October 3, 2012

Exterior Waterproofing on Historic Buildings

We're heading into the fall rainy season again and Great Lakes Waterproofing is leading the way with exterior waterproofing. While we work with most products and systems available, sealing the foundation from the exterior is our preferred method.  A lot of our Bentonite waterproofing projects involve older, maybe even historic, structures.  Bentonite (Hydroclay) Waterproofing works great because it fills in voids, follows the water and seals the passageways.  Once properly set up the foundation will have the time-tested proven properties of Bentonite.

Historic and older properties can be a little more difficult to address for exterior waterproofing, buildings were often built closer to sidewalks and parking lots.  If excavation were necessary the costs would go up tremendously.  Great Lakes Waterproofing addresses these issues by drilling small holes around the perimeter and pumping under the obstruction.  this building is typical of what you might find in the downtown district, construction is solid stone foundation and brick above grade with an asphalt patio area.  Water is coming in through this side so that's the area we'll do our exterior waterproofing.      

After drilling several small holes near the foundation, we pump our Bentonite sealing up this part of the wall.  In the photo is an injection wand, extending down around 8'-10', and hose that's connected to the pumping equipment.  Our industrial pumping equipment is capable of pumping long distances, this patio area was sealed off by a fence and we only had limited access, not only would excavating this area be difficult, most of it would have to be done by hand. 

The front side of this building also presented it's own challenges, even with the concrete all the way up to the foundation, this building had major water issues.  The solid stone walls were fine but over time some of the mortar joints opened up allowing free-flowing water to enter the building.  Since the water was entering above the floor and the wall was solid, the owner decided to go with exterior waterproofing.  Excavation and digging were cost prohibitive but Bentonite waterproofing seemed like the perfect product for this application.

After drilling small holes along the perimeter, Bentonite is pumped all the way down to the footings (basement floor level), this photo is neat because you can see the clay coming back up a hole that's over six feet away.  Once the Bentonite sets up, the water that used to flow in this "void" will not be able to pass through the Bentonite. 


Unknown said...

Thank you for all this great information about exterior waterproofing! I really like your point about how you can avoid higher costs by drilling small holes around the property. My husband and I just bought a home built in the 1800, so we might have look into these options.

Joana said...

Please make sure to inspect your drywall systems thoroughly if there are any issues with waterproofing.