Project Overview

A Brooklyn, NY homeowner needed help with a foundation wall that had several areas requiring repair and waterproofing. The problem included a pipe passing through the foundation wall, a below-grade window, damaged masonry, and an improperly installed house wrap around the rim joist.

Because several parts of the exterior wall were involved, simply sealing one area would not have addressed the entire problem.

Our team developed a repair plan that included excavation, foundation wall preparation, high-strength repair mortar, pipe sealing, liquid rubber waterproofing, a vapor barrier, rim joist waterproofing and proper backfilling. We also restored the brick wall, closed the below-grade window and rebuilt the exterior surface.

The goal was to repair the damaged foundation wall, seal vulnerable areas and restore the backyard area after the waterproofing work was completed.

The Problem: Damaged Foundation Wall and Multiple Water Entry Points

The foundation wall had several areas that needed attention.

One of the main concerns was a pipe passing through the foundation wall. The area around the pipe needed to be exposed so our team could properly inspect and seal the connection between the pipe and the foundation.

The foundation wall itself also had damaged and foreign material on its surface. This prevented us from properly applying a repair and waterproofing system without first preparing the masonry.

There was also an existing window below grade that needed to be closed off. The surrounding brick wall required cleaning and restoration.

Another concern was the rim joist. The existing house wrap had been improperly installed and did not provide the level of protection needed at this vulnerable area.

The combination of these conditions meant the repair needed to address the foundation wall, pipe penetration, below-grade window, rim joist and surrounding masonry as part of one coordinated project.

The Solution: Excavation, Foundation Repair and Waterproofing

Zavza Seal began by excavating along the affected foundation wall.

The excavation was taken deep enough to reach approximately 1 foot below the pipe. This gave our team access to the area around the pipe and the portion of the foundation that needed to be repaired and waterproofed.

For the additional work, we extended the excavation in a U-shaped area approximately 10 linear feet, with approximately 2 feet extending around each corner toward the adjacent walls.

This allowed us to address the surrounding foundation instead of treating only one small section.

Preparing the Foundation Wall

Once the affected area was exposed, our team thoroughly prepared the foundation surface.

We scarified and steel-brushed the wall to remove damaged and foreign materials. This exposed the bare stone and created a properly prepared surface for the repair mortar.

Proper surface preparation is an important part of masonry repair. Applying new material over loose or damaged material can compromise the repair.

After preparation, we applied approximately 1 inch of 6,500 PSI repair mortar to the exposed foundation surface.

The high-strength mortar helped restore the prepared section of the foundation wall and create a solid surface for the waterproofing system.

Sealing Around the Foundation Pipe

The area between the pipe and foundation wall was another important part of the repair.

Our team injected Sikawell S2 into the space between the pipe and the foundation.

The purpose was to seal the vulnerable joint where the pipe passed through the foundation wall.

Pipe penetrations can create potential pathways for water when the surrounding area is not properly sealed. Addressing this connection was therefore an important part of the overall waterproofing work.

Waterproofing the Foundation Wall

After the foundation surface was repaired and prepared, our team applied a heavy layer of waterproofing mortar to the affected areas.

We then applied liquid rubber over the prepared surface.

The waterproofed wall was subsequently covered with a 20-mil vapor barrier to provide another protective layer below grade.

The waterproofing system was designed to create a continuous barrier over the repaired foundation surface and protect the wall from moisture coming through the surrounding soil.

Closing the Below-Grade Window

The project also included an existing window located below grade.

Because the opening was part of the affected foundation area, our team installed cinder blocks to close off the window.

We then cleaned the remaining adjacent surfaces and prepared and restored the surrounding brick wall.

A heavy layer of 6,500 PSI waterproofing mortar was applied to the prepared surface, followed by a coat of liquid rubber.

This allowed the former window area and surrounding masonry to be incorporated into the overall waterproofing work rather than leaving an exposed weak point.

Repairing the Rim Joist Waterproofing

The foundation wall was not the only area that required attention.

Our team also found improperly installed house wrap around the rim joist.

We removed the existing house wrap and installed a new self-adhering membrane to waterproof and seal the rim joist.

This was an important part of the project because the rim joist sits where the foundation and framing meet. Protecting this transition helps reduce the risk of moisture entering through the joint.

Proper Backfilling and Drainage Base

After the waterproofing work was completed, we began restoring the excavated area.

Rather than simply filling the excavation all at once, the soil was backfilled and tamped in lift phases.

This helped compact the soil as the excavation was restored.

We also installed a gravel bedding and poured a new concrete base as part of the exterior restoration.

Proper backfilling is an important part of any foundation excavation project. Poorly compacted soil can settle later and create problems for the surface above.

Restoring the Exterior Surface

The work did not stop after the foundation was waterproofed.

Our team also restored the area above the completed foundation work.

We installed approximately 1 inch of bedding for large-format tile and prepared the surface for the final exterior finish.

An aluminum L flashing was installed behind the siding with a slope away from the house. This helped direct water away from the wall instead of allowing it to collect against the foundation.

Finally, the pavers were reinstalled to complete the restoration.

The goal was to leave the property with both the foundation repair and the surrounding exterior work completed.

The Result

The Brooklyn foundation repair project addressed several problems in one coordinated scope of work.

The damaged foundation wall was repaired and waterproofed. The space around the pipe was sealed, the below-grade window was closed, and the adjacent brickwork was restored.

The rim joist also received a new self-adhering waterproofing membrane after the improperly installed house wrap was removed.

Once the below-grade work was complete, the excavation was properly backfilled and compacted. The gravel bedding, concrete base, tile bedding, flashing and pavers were then installed to restore the exterior area.

The result was a repaired, sealed and waterproofed foundation wall with the surrounding exterior restored.

Need help with a foundation wall or waterproofing problem in Brooklyn? Contact Zavza Seal to schedule an inspection.