Key takeaways
- Watch for horizontal or stair-step cracks, bowing walls, leaks and sticking doors.
- Water is the leading cause of foundation damage in NJ.
- Older Bernardsville homes often have stone or brick foundations that need repointing.
- Fixing grading and drainage prevents repairs from failing.
Many Bernardsville homes are decades or even a century old, built on stone, brick or block foundations, and set into the Somerset Hills where water runs downhill toward them. Foundation problems caught early are far easier and cheaper to fix.
Warning signs
- Horizontal cracks or stair-step cracks in block walls
- Cracks that are widening or wider than about 1/8 inch
- Bowing or bulging walls
- Water seeping through cracks or at the wall-floor joint
- Crumbling mortar in stone or brick foundations
- Sticking doors and windows, or new drywall cracks
What causes foundation damage
Water is the main culprit. Saturated soil pushes against walls, freeze-thaw cycles expand cracks, and poor grading or clogged gutters send roof water straight to the foundation. On hillside properties, uphill runoff adds even more pressure.
Repair approaches
- Crack sealing for leaking non-structural cracks
- Repointing stone and brick foundations with compatible mortar
- Rebuilding deteriorated block or masonry sections
- Parging to protect exterior foundation faces
- Drainage corrections: grading, downspouts, footing drains and waterproofing
Where significant movement is present, we recommend a structural engineer’s evaluation and build to their specifications.
See foundation repair and basement waterproofing.
Troubleshooting: common problems and fixes
Here’s how we diagnose and fix the issues we see most often on projects like this.
Aging estate driveways and motor courts
What you see: Long drives with raveling asphalt, broken Belgian block and settled areas.
Why it happens: Age, heavy service vehicles and runoff on hilly terrain.
How we fix it: Rebuilding failed sections, resetting or replacing Belgian block, and overlays or full replacement with heavier sections.
How to prevent it: Sealcoat and crack-seal regularly to protect a large investment.
Stone walls and pillars leaning or loose
What you see: Leaning dry-laid walls and loose caps on entrance pillars.
Why it happens: Frost movement, roots and missing footings.
How we fix it: Rebuild on proper footings, reset caps and repoint with compatible mortar.
How to prevent it: Keep plows and vehicles away from pillars.
Horizontal crack in a block wall
What you see: A horizontal crack along a mortar joint, often mid-height, sometimes with the wall bowing inward.
Why it happens: Soil pressure, often from saturated or frozen clay, pushing on the wall.
How we fix it: This needs prompt evaluation. Depending on severity, repair ranges from reinforcing and rebuilding the affected section to engineered solutions. We work to engineer specifications where required.
How to prevent it: Reduce water against the wall through grading, gutters and drainage.
Water at the wall-floor joint
What you see: A wet line around the edge of the basement floor after rain.
Why it happens: Hydrostatic pressure. Saturated soil pushes water through the cold joint between the footing, wall and slab.
How we fix it: An interior perimeter drain at the footing collects the water and sends it to a sump pump, relieving pressure.
How to prevent it: Manage roof water and grading so less water reaches the foundation.
Stair-step cracks
What you see: Cracks stepping diagonally through block mortar joints.
Why it happens: Differential settlement or soil pressure.
How we fix it: We repair and repoint, rebuild where blocks have moved, and address drainage and soil causes.
How to prevent it: Monitor cracks with dated pencil marks.
What affects the cost
- Type and severity of damage
- Wall material: poured, block, stone, brick
- Interior vs. exterior access
- Engineering where required
- Drainage corrections
- Interior vs. exterior approach
- Linear feet of drainage
Mistakes to avoid
- Caulking over a structural crack
- Ignoring water causes
- Using cement mortar on old stone
- Waiting until a wall bows
- Painting walls with waterproof paint and calling it fixed
- Ignoring gutters and grading
Seasonal care checklist
- Spring: Inspect walls after the thaw.
- Summer: Best season for exterior work.
- Fall: Fix gutters.
- Winter: Watch for new cracks and leaks.
Frequently asked questions
Are small foundation cracks normal?
Thin vertical shrinkage cracks are common, but horizontal, stair-step or widening cracks need professional evaluation.
Can old stone foundations be repaired?
Yes. Repointing and rebuilding with compatible mortar restores stone foundations.
How do I know if a foundation crack is serious?
Horizontal cracks, stair-step cracks in block, cracks wider than about 1/8 inch, or cracks that are growing should be evaluated promptly.
Will waterproof paint fix a wet basement?
Not on its own. Paint can’t hold back water pressure. The water needs to be managed with drainage, crack repair and grading.
Do I need a battery backup for my sump pump?
In New Jersey, yes. Storms that cause flooding often cause power outages too.
Planning a project? Old Irish Paving & Masonry is a family-owned, licensed and insured New Jersey contractor with 30+ years of experience. Call (908) 992-2345 or request a free estimate.