Waterproofing Service in Chicago, IL
Masonry Waterproofing and Sealing for Chicago Buildings
Waterproofing is how you protect the investment after the repair work is done. Tuckpointing seals the mortar joints. Brick replacement restores structural integrity. But without a breathable sealer on the masonry surface, moisture still absorbs into the brick and mortar, and the freeze-thaw cycle starts breaking things down again. We apply masonry waterproofing on buildings across Chicago every week, from residential greystones in Lincoln Park and two-flats in Bridgeport to commercial facades in the West Loop and condo buildings along Lakeview‘s lakefront.
North Shore Masonry has been waterproofing Chicago masonry since 1978. We use breathable, penetrating water repellents that soak into the brick and mortar to prevent moisture absorption while still allowing internal moisture vapor to escape outward. This distinction matters. Non-breathable coatings trap moisture inside the wall, which causes the same spalling damage the waterproofing was supposed to prevent. We also handle all related caulking and sealant work: expansion joints, window and door perimeters, coping joints, and flashing connections.
Whether you need a post-restoration seal on a newly tuckpointed wall in Logan Square, expansion joint caulking on a condo building in Streeterville, or a full waterproofing application on a CMU block building in Uptown, our crews handle projects of every scope. Call (847) 864-5990 to schedule a free evaluation.
How We Handle Masonry Waterproofing in Chicago
Waterproofing is the final step in protecting a masonry wall. But it only works if the wall is properly prepared first. Applying sealer over cracked mortar, open joints, or failed caulking is a waste of material and money.
We inspect the masonry surface for open mortar joints, cracked sealant, damaged flashing, and any active moisture entry points. Waterproofing seals the surface, but it cannot seal gaps in the mortar or failed caulking joints. If we find deteriorated mortar, we recommend tuckpointing before applying the sealer. On buildings in Wicker Park and Humboldt Park, we frequently find that prior waterproofing applications failed because the mortar joints were never addressed first.
The masonry surface must be clean and dry before sealer application. We remove dirt, efflorescence, biological growth, and any prior coatings that would prevent the sealer from penetrating properly. On heavily soiled surfaces, we use low-pressure washing or chemical cleaning to prepare the brick without damaging the mortar joints.
Before the masonry sealer goes on, we replace all failed caulking at expansion joints, window and door perimeters, coping joints, and any penetrations through the wall (pipes, vents, utility connections). These joints are the most common moisture entry points on Chicago buildings. We use polyurethane or hybrid sealants matched to the joint type and exposure conditions. On condo buildings in the South Loop and Streeterville, expansion joint failure is one of the primary drivers of tenant leak complaints.
We apply a professional-grade breathable water repellent by spray or roller, ensuring full saturation of the masonry surface. The sealer penetrates into the brick and mortar to form a hydrophobic barrier that repels water while allowing moisture vapor from inside the wall to escape outward. We select the sealer type based on the substrate: silane-based for deep penetration on dense brick, siloxane-based for porous surfaces, and specialized formulations for CMU block, limestone, and concrete.
After application, we verify coverage, check for any missed areas, and confirm the sealer is absorbing properly. We document the product used, application rate, and coverage area for the building’s maintenance records. Breathable masonry sealers typically last 5 to 10 years depending on exposure conditions. All waterproofing work is backed by our 2-year labor and material warranty.
Common Waterproofing Problems on Chicago Buildings
Moisture is the root cause of most masonry deterioration in Chicago. Here are the specific waterproofing failures we diagnose and correct across the city.
Most common issue
No waterproofing after tuckpointing or masonry repair
The most common waterproofing failure is not having any. A building gets tuckpointed, the brick gets replaced, the owner pays for the work, and then no sealer is applied. The fresh mortar and bare brick start absorbing moisture immediately. Within a few Chicago winters, the new mortar is already beginning to erode. Sealing the wall after repair is the most cost-effective way to extend the life of the work. We recommend it on every project, and many of our tuckpointing and brick repair customers add waterproofing as part of the same scope.
A previous contractor applied a film-forming sealer or elastomeric coating that sealed the surface but trapped moisture inside the wall. The brick cannot release internal moisture vapor, so it spalls from the inside. We see this on buildings in Hyde Park and Edgewater where a “waterproof” coating was applied without understanding the difference between breathable and non-breathable products.
Expansion joints allow the building to move with temperature changes. When the caulking in these joints fails, it creates a direct path for water to enter the wall cavity. This is one of the most common sources of persistent interior leaks on Chicago condo buildings, especially newer construction in Streeterville and the South Loop.
Failed sealant around window and door frames is a primary moisture entry point. Water runs down the wall face, enters at the frame, and shows up as interior staining or mold. Recaulking these joints with the correct sealant and proper backer rod installation stops the problem at the source.
Concrete masonry unit (CMU) block walls are more porous than brick and absorb water more readily. Split-face CMU, common on Chicago commercial and multi-unit buildings, is especially vulnerable. Without a breathable sealer, these walls saturate in heavy rain and transfer moisture to the interior. The sealer application often needs two coats on CMU due to higher absorption rates.
Signs Your Building Needs Waterproofing
Moisture problems in masonry are often visible before they become serious. Here is what to look for:
White salt deposits mean moisture is traveling through the wall and depositing minerals on the surface as it evaporates. The wall is absorbing and releasing water.
Moisture showing through on the inside wall, especially after rain. The exterior masonry is not keeping water out.
Persistent moisture behind the wall creates conditions for mold. Waterproofing the exterior stops the moisture source.
Visible gaps where caulking has separated from window frames, expansion joints, or coping stones. Each gap is an open path for water.
If the brick face gets noticeably darker when wet and takes hours to dry, the masonry is absorbing water. A breathable sealer prevents this absorption.
If you are seeing any of these signs, call (847) 864-5990 for a free evaluation. Waterproofing is one of the most cost-effective ways to protect your building’s masonry long-term.
Waterproofing for Homes and Commercial Buildings
Single-family homes, two-flats, and three-flats. Most residential waterproofing involves sealer application after tuckpointing or brick repair, caulking around windows and doors, and treating foundation walls that show moisture transfer. A typical residential waterproofing project takes one to two days. We protect windows, landscaping, and adjacent surfaces during application.
Condo buildings, commercial facades, and CMU block structures. Larger buildings often need full-elevation sealer application combined with comprehensive caulking replacement at all expansion joints, window perimeters, and coping connections. We work with property managers and condo boards on phased scoping and scheduling. For cost guidance, visit our pricing page.
Why Chicago Property Owners Trust Our Waterproofing
Certified Member of the Mason Contractor Association of America (MCAA)
"Committed to preserving and promoting the masonry industry by providing continuing education, advocating fair codes and standards, fostering a safe work environment." - MCAA
Where We Provide Waterproofing Around Chicago
Our waterproofing crews work throughout Chicago and surrounding Chicagoland communities. For full masonry services in your area, visit our Chicago masonry contractor page or select a location below.
Core Service Areas
Oak Park, IL
Berwyn, IL
Cicero, IL
Skokie, IL
Elmhurst, IL
Wilmette, IL
Highland Park, IL
Kenilworth, IL
Extended Coverage