All 5 Boroughs · Licensed & Insured · LPC-Compliant
From Park Slope stoops to Harlem facades, from Bed-Stuy brownstones to Riverdale brickwork — Keystone Restorations repairs, restores, and protects New York’s historic masonry the right way. No shortcuts. No wrong mortar. No permit headaches left for you to handle.
Who We Are
Keystone Brownstone Restoration has been preserving the architectural soul of New York City for over two decades. We know that a 130-year-old brownstone isn’t just a building — it’s a piece of the city’s identity. That’s why we treat every project with the craftsmanship, proper materials, and regulatory knowledge it demands.
Too many property owners have learned the hard way what happens when a contractor uses hard Portland cement on soft brownstone, or skips the LPC filing because “it’s just a small repair.” We’ve seen the cracks, the spalling, the water infiltration, the DOB violations. We exist to make sure that never happens to you.
Every project we take on — from a single stoop repoint in Staten Island to a full facade restoration on a landmarked Harlem townhouse — gets the same meticulous, code-compliant treatment.
Brownstone Facades Restored
Years Serving NYC
Boroughs Covered
LPC Filings Approved
We handle every aspect of your brownstone’s exterior — from the mortar joints between bricks to the ornamental cornice at the roofline. All work is performed to NYC DOB standards and Landmarks Preservation Commission guidelines.
Full assessment, color-matched patching, lime consolidant treatment, and pigmented coating restoration. We restore original sandstone facades to their historical character using materials compatible with the existing stone — no Portland cement shortcuts.
We remove deteriorated mortar to the proper depth (minimum ¾"), clean joints, and apply correctly formulated mortar matched to your brick's hardness and porosity. We use Type S or NHL lime mortars for historic buildings — never hard Portland cement that damages soft brick.
NYC stoops take tremendous wear. We rebuild deteriorating stoop walls, replace cracked treads and risers, restore handrails, and repair sidewalk vault waterproofing beneath the stoop — addressing root causes, not just surface symptoms.
If your property is in a NYC Historic District, we manage the entire Landmarks Preservation Commission process — from Certificate of No Effect (CNE) for in-kind repairs to Certificate of Appropriateness (CofA) for facade changes. You don't navigate the bureaucracy; we do.
Failing parapet walls are both a DOB violation and a genuine safety hazard. We rebuild, repoint, and waterproof parapet walls to bring them into full compliance, eliminating violations and protecting the people below from falling masonry.
Water is the single greatest threat to brownstone. After restoring your masonry, we apply breathable, penetrating sealers appropriate for historic sandstone and brick — protecting without trapping moisture inside the wall, which is a common cause of accelerated damage.
Chimneys are the first place water gets in. We repoint chimney crowns, replace deteriorated flashing, rebuild damaged caps, and restore the masonry from crown to firebox — preventing interior water damage before it starts.
Received a NYC Department of Buildings violation for unsafe facade conditions, failing brickwork, or parapet issues? We have an established track record of efficiently resolving violations — from inspection to repairs to official sign-off — including FISP (Local Law 11) compliance for larger buildings.
Not sure how serious the damage is? We perform thorough facade assessments — including sounding tests, moisture readings, and mortar analysis — to give you an honest, documented picture of your building's condition before any work begins.
No matter where your brownstone or brick building is located in New York City, Keystone Restorations brings the same standard of expertise, the same materials, and the same commitment to your property.
After two decades in this industry, we’ve repaired the damage done by other contractors more times than we can count. Here’s what separates us from contractors who say they do historic masonry but don’t truly understand it.
Portland cement is harder than the brownstone and historic brick it's placed against. It traps moisture, concentrates freeze-thaw stress at the mortar-stone interface, and causes accelerated spalling. We use NHL (Natural Hydraulic Lime) or Type S lime mortars — always matched to the existing masonry through analysis, not guesswork.
Many contractors leave the Landmarks Preservation Commission process entirely to you. We manage the full filing — from initial CNE or CofA application to test panel preparation and LPC inspection coordination. Our 100% LPC approval rate speaks for itself.
Cracks and spalling are symptoms. The cause is usually water infiltration — from a failed stoop waterproofing, a deteriorated cornice, or improper caulking at window surrounds. We fix what's causing the damage, so it doesn't come back.
High-pressure water is the number-one contractor error on brownstone. It destroys the surface layer of soft sandstone irreversibly. We use low-pressure chemical cleaning and hand methods only — techniques that clean without accelerating decay.
Your contract specifies exactly what work is being done, what mortar type and brand, what color-matching process, who handles permits, and your workmanship warranty terms. No vague scopes. No surprise charges. No "we thought you meant something else."
We stand behind every job with a written workmanship warranty. If something goes wrong due to our work or materials within the warranty period, we come back and fix it. Period.
Any contractor who says this about exterior work on a Landmarks-designated property is either uninformed or hoping you don't find out about the violation until after they've been paid. Unpermitted exterior work in a historic district can freeze your property sale, trigger stop-work orders, and require costly teardown and redo work at your expense.
A contractor who starts grinding joints without first testing what mortar is in there doesn't understand historic masonry. Original brownstone buildings used lime mortars. Repointing over them with a harder mortar mix destroys the stone, not just the joint.
"Repoint front facade" is not a scope of work. It doesn't say how deep the joints will be ground, what mortar will be used, whether scaffolding is included, what happens to ornamental details, or who is responsible for permits. Ambiguity is how you get substandard work with no recourse.
Already got a quote from another contractor? We'll review their scope of work and tell you honestly if it's appropriate for your building. No charge, no pressure. Call 646-919-4496.
Crew-wide certification
RRP Cert. #NAT-F213
Workers' Comp included
Every Keystone project follows the same proven sequence — designed to protect you from surprises and deliver results that last decades, not years.
We come to your property, walk the facade, sound the masonry, identify deterioration patterns, check for water infiltration sources, and review your Landmarks designation status.
You receive a line-by-line estimate: scope of work, mortar specification, materials, scaffolding costs, permit fees, timeline, and warranty terms. No surprise additions later.
For Landmarks properties, we file for your Certificate of No Effect or Certificate of Appropriateness and coordinate all DOB permits. You don't attend hearings or navigate agency websites.
Before full-scale work begins, we prepare test panels for mortar color and brownstone patch color approval — ensuring the restoration is invisible, not obvious.
Before full-scale work begins, we prepare test panels for mortar color and brownstone patch color approval — ensuring the restoration is invisible, not obvious.
We walk the completed work with you, address any questions, and provide your written workmanship warranty documentation. We also advise on a simple annual maintenance routine to extend the life of the restoration.
We believe in transparency. Here are honest price ranges for the most common work we do in New York City. Your exact cost depends on building size, condition, accessibility, and Landmarks requirements. We’ll give you a precise number after our free assessment.
| Service | Typical Range (2026) | Notes |
|---|---|---|
| Brick Pointing / Repointing | $15 – $35 per sq ft | Standard residential; 3-story brownstone front facade: $10,000 – $25,000 |
| Brownstone Facade Patching & Coating | $28,000 – $65,000 | Standard 20×40 rowhouse facade; includes color-matched pigmented finish |
| Full Brownstone Facade Restoration | $85,000 – $250,000+ | True stone replacement using quarried brownstone; ornamentation extra |
| Stoop Restoration / Rebuild | $18,000 – $60,000 | Includes vault waterproofing under stoop: add $12,000 – $35,000 |
| Parapet Wall Repair | $8,000 – $30,000 | Depends on run length, condition, and whether rebuilding is required |
| Chimney Repair & Crown | $2,500 – $15,000 | Full chimney rebuild from roof line: additional cost |
| LPC Filing & Permit Handling | Included in project scope | CNE (same-day) or CofA (3-6 month process for major changes) |
| DOB Violation Removal | Quote after inspection | Includes all repair work, inspections, and sign-off coordination |
Important: Any quote significantly lower than these ranges almost always indicates wrong mortar type, insufficient joint depth, missing permits, or cutting corners on material matching. We’re happy to review any other estimate you’ve received and tell you what’s missing from it.
Most of brownstone Brooklyn, Harlem, and many other NYC neighborhoods fall within designated Landmarks Historic Districts. This means any exterior repair — even repointing mortar joints — technically requires Landmarks Preservation Commission review before work begins.
Contractors who ignore this leave you exposed to stop-work orders, fines, and violations that can halt a property sale, complicate refinancing, and require costly removal of unpermitted work. We’ve seen it happen dozens of times.
Keystone Restorations has a dedicated process for LPC filings. We photograph the existing conditions, document material specifications, prepare test panels, and submit through the LPC’s Portico system on your behalf. Our submission record speaks for itself: 100% of our LPC applications have been approved.
Key NYC Historic Districts we regularly work in: Park Slope, Brooklyn Heights, Boerum Hill, Carroll Gardens, Clinton Hill, Cobble Hill, Crown Heights, Bedford-Stuyvesant, Fort Greene, Harlem, Hamilton Heights, Upper West Side, Upper East Side, Greenwich Village, NoHo, SoHo, Riverdale, and more.
Understanding which one your project needs prevents costly delays.
Portland cement is harder than the brownstone and historic brick it's placed against. It traps moisture, concentrates freeze-thaw stress at the mortar-stone interface, and causes accelerated spalling. We use NHL (Natural Hydraulic Lime) or Type S lime mortars — always matched to the existing masonry through analysis, not guesswork.
Small-scale alterations with minimal visibility impact. Faster than a full CofA hearing.
Required when changing facade materials, altering cornice profiles, resizing openings, or any visible change from original. Full Landmarks hearing; allow 3–6 months.
A standard repointing project on a 3-story brownstone takes 1–3 weeks on-site. Full facade restoration including LPC approval can take 2–6 months total (mostly waiting on LPC), with the actual construction portion taking 3–8 weeks depending on scope.
Repointing refers to removing old mortar and applying fresh mortar to joints. Tuckpointing is a specific finishing technique using two different mortar colors — a base mortar color matching the brick, with a thin line of contrasting mortar in the center. Both are offered by Keystone Restorations.
Call today for a free, no-pressure facade assessment. We’ll tell you exactly what your building needs, what it will cost, and what permits are required — before you commit to anything.
Keystone Brownstone Restoration Contractors & Brick Pointing NYC
Serving Manhattan · Brooklyn · Queens · Bronx · Staten Island
Licensed & Insured · LPC Landmark Specialists · Free Estimates
