The area where the leaks persisted were directly below the sidewalk where the concrete meets the asphalt driveway.  After inspecting the above ground conditions closely it was determined that the main source of the water intrusion were gutter downspouts. There were no drains installed to manage the directional flow of rainwater away from the structure.

Now that the source and path of water ingression had been established, polyurethane pressure injection of the affected areas was confirmed to be the correct solution to seal the leaks. 

The first areas that needed to be sealed were leaking beam pockets which had been previously filled with a mastic patch grout. Over a 30 year period there had been multiple previous attempts by various contractors to repair the leaking areas. No records were available on the various works that had been performed.

It was decided to inject through the wall to the back side of the structure to cut off any water before it could find its way into the beam pockets. This method combines void fill and permeation grouting as product is injected beyond the structure into a space that in this instance is confined by concrete / steel, asphalt and dirt. As the foam disperses under pressure injection and during expansion, it partially migrates / permeates also into the dirt further enhancing the ability to seal the void.

Using two strategically placed SealBoss Evolution 13-100 AL packers, the contractor injected 1510 Water Stop Foam, catalyzed with 10% 15x Accelerator,  at several intervals, permitting the resin to expand to a dense foam creating a seal and protecting the beam pocket from any water intrusion from behind the wall. 

The injection process was monitored from the inside and outside and the contractor stopped injection once air bubbles and water were observed coming up through the asphalt driveway. Expanding foam displaced water in the affected area. Injection was continued at a slow rate until water displacement  finished and increasing resistance indicated full penetration.

Next, the contractor injected all visible and leaking cracks some of which at one point had been injected with a structural / rigid epoxy which had failed. Reason of epoxy failure was determined as either lack of bond due to actively leaking cracks during epoxy injection and/or failure due to crack movement such as contraction and expansion. Polyurethane injection is the preferred method to address actively leaking and water bearing cracks, especially in areas where structural repairs are not necessary. The two foot thick wall was injected with 1510 leak-seal foam in intervals till the crack showed refusal of the resin.

Epoxy Versus Polyurethane Comparison – click here.

On-site support from knowledgeable and experienced technical reps is available upon request, I personally cover from North Dakota and Minnesota down through Texas.  Call us with any questions, we look forward to helping you find a solution.