All 5 Boroughs · Licensed & Insured · LPC-Compliant

Masonry contractors in the Bronx

Brick, block, stone and concrete , repointing, sidewalks, stoops, chimneys, retaining walls and waterproofing. We work on Bronx one- and two-families, brownstones, walk-ups and small commercial buildings.

Get a free quote!

Masonry services across the Bronx

One crew, one point of contact, from a cracked sidewalk flag to a full parapet rebuild. Every job gets a written scope and a fixed price before anyone picks up a trowel.

BRICK , Pointing & repointing

Grinding out failed mortar and repacking joints with a mix matched to your existing wall , the fix for spalling brick, damp interiors and open head joints.

BRICK , Brick & block repair

Cracked, bulging or blown-out sections cut out and rebuilt. Lintel replacement, brick matching on older Bronx housing stock, and full wall rebuilds.

CONCRETE , Sidewalks & curbs

Flag replacement and full sidewalk pours to NYC DOT spec, including curb cuts, tree pit repair and trip-hazard grinding.

CONCRETE , Stoops & steps

Rebuilt front stoops, cellar steps and landings in brick, block, bluestone or poured concrete , with railings reset and pitched to drain.

CONCRETE , Driveways & patios

Poured concrete, stamped finishes and paver installs over a properly compacted base, so the slab doesn't sink through its first Bronx winter.

STRUCTURE , Retaining walls

Block, poured or segmental walls with drainage, geogrid and weeps built in. We straighten leaning walls and rebuild the ones past saving.

ROOFLINE , Chimneys & parapets

Crown repair, flue and liner work, chimney rebuilds above the roofline, and parapet coping resets that stop water tracking down the wall.

WATER , Waterproofing

Exterior membranes, cellar entrances, area-way drainage and foundation crack repair for basements that take on water every heavy rain.

STONE , Stone & bluestone

Natural and veneer stone facing, bluestone treads and caps, window sills, columns and garden walls cut and set on site.

NYC sidewalk violations, handled end to end

If DOT has flagged your sidewalk, the clock is running and the City can do the work itself and bill you for it. We measure the defective flags, price the repair, do the pour to City spec, and stay on it until the violation clears.

How a job runs

No surprise change orders. You’ll know the scope, the price and the schedule before we mobilize.

Call or send photos

Tell us what's failing. A few phone photos are usually enough for us to tell you the likely fix and rough range.

Site visit

We come out, measure, check the cause , not just the symptom , and look at drainage, flashing and grade.

Written estimate

An itemized scope with materials, quantities, timeline and a fixed price. Free, and yours to compare.

Build

Site protected, work done to schedule, debris hauled daily. You get progress photos if you're not home.

Walkthrough

We walk the finished work with you, clean the site down, and hand over care notes and your warranty terms.

How a job runs

No surprise change orders. You’ll know the scope, the price and the schedule before we mobilize.

Repointing · Williamsbridge

Sidewalk pour · Baychester

Stoop rebuild · Throggs Neck

Chimney rebuild · Morris Park

Paver driveway · Pelham Bay

Every corner of the Bronx

Based on Laconia Avenue in Williamsbridge, so most of the borough is a short drive. We also take work in lower Westchester.

Bronx ZIP codes: 10451 · 10452 · 10453 · 10454 · 10455 · 10456 · 10457 · 10458 · 10459 · 10460 · 10461 · 10462 · 10463 · 10464 · 10465 · 10466 · 10467 · 10468 · 10469 · 10470 · 10471 · 10472 · 10473 · 10474 · 10475
Also serving: Mount Vernon · Yonkers · Pelham · Pelham Manor · New Rochelle · Eastchester, NY

What NYC Homeowners Say

★★★★★
Our Park Slope brownstone had been repointed by a previous contractor with the wrong mortar and the facade was actively spalling. Keystone came out, explained exactly what had happened and why, matched our original stone color perfectly, and handled the LPC filing without us lifting a finger. The facade looks like it was built yesterday.
— M. Okafor
Park Slope, Brooklyn
★★★★★
We had a DOB violation for an unsafe parapet on our Harlem brownstone and were panicking about the timeline. Keystone handled everything — the emergency inspection, the repair scope, the DOB permit, the actual rebuilding work, and the final sign-off. From violation to clearance in six weeks. Incredibly professional.
— D. Santiago
Hamilton Heights, Manhattan
★★★★★
I got three quotes for brick pointing on our three-story rowhouse in Ridgewood. Keystone wasn't the cheapest, but they were the only contractor who told me what mortar type they'd use and why, showed me photos of similar projects, and put everything in writing. The other guys couldn't even tell me if we needed an LPC permit. Choose Keystone.
— T. Bernstein
Ridgewood, Queens
★★★★★
My stoop was crumbling and the sidewalk vault below was leaking into my basement every time it rained. Keystone restored the stoop, waterproofed the vault, and repointed the entire front facade. Completely dry basement ever since. I wish I'd called them before paying someone else $4,000 for a patch job that lasted two seasons.
— C. Williams
Crown Heights, Brooklyn
★★★★★
As a property manager overseeing 14 buildings across Brooklyn and the Bronx, I've worked with a lot of masonry contractors. Keystone is the only company I trust for historic brownstone work. Their LPC knowledge alone saves me weeks of headaches on every project.
— A. Russo
Property Manager, Brooklyn & Bronx
★★★★★
The chimney above our Riverdale co-op was deteriorating badly and leaking into the top-floor unit. Keystone rebuilt the chimney stack, replaced the flashing, repointed the entire roof-level brickwork, and had everything done in one week. Clean, professional, and exactly on the quoted price.
— K. Patel
Riverdale, The Bronx

Questions we get every week

Something not covered here? Call and ask , we’d rather talk it through than have you guess.

Yes. We repair or replace the cited flags to current NYC Department of Transportation specifications, including curb and tree-pit work where it's part of the notice. Send us a photo of the violation and we'll tell you what's involved before we come out.

It depends on the scope. Cosmetic repointing and flag replacement usually don't need a DOB permit, while structural work, facade work above a certain height, sidewalk sheds and anything touching the building envelope generally do. We tell you upfront which category your job falls into and pull what's needed.

Price comes down to square footage, access, how much demolition is involved, the material you choose, and whether we're fixing a symptom or the cause behind it. That's why we don't quote over the phone , you get a free on-site measure and an itemized written estimate you can hold us to.

If the brick faces are sound and it's the mortar joints that have eroded, repointing is the right call and far cheaper. Once brick is spalling, cracked through, or the wall is bulging, that section needs to be cut out and rebuilt. We'll show you which one you're looking at on the site visit.

As a rule of thumb, foot traffic after about 24–48 hours and vehicles after about seven days, though cold weather slows curing considerably. We give you exact timing for your pour and the weather that week, plus how to protect it through the first winter.

Yes, with precautions. Mortar and concrete need protection below roughly 40°F, so we use heated enclosures, blankets and cold-weather mixes when the job can't wait. If a job genuinely shouldn't be poured in February, we'll tell you that instead of taking the deposit.

Yes , we carry general liability and workers' compensation coverage, and we'll email certificates before work starts. Co-op and condo boards can have them sent directly to management.

Estimates are usually scheduled within a couple of days, and small repairs often get slotted in the same week. Larger rebuilds depend on the season and permitting. Emergency work , a loose parapet, a collapsed step, an active leak , moves to the front of the line.

Free estimates, 7 days a week

Let's look at the job

Call (347) 348-0283 and you’ll get a mason on the phone, not a call center. Or send the form and we’ll come back to you the same day.

Monday6:00 am – 8:00 pm
Tuesday6:00 am – 8:00 pm
Wednesday6:00 am – 8:00 pm
Thursday6:00 am – 8:00 pm
Friday6:00 am – 8:00 pm
Saturday6:00 am – 8:00 pm
Sunday6:00 am – 8:00 pm

Request an estimate

Tell us what’s going on. Photos help — you can send them by text to the same number.

NYC sidewalk repair, DOT violation removal & premium paver installation. Licensed, insured, and built to last.