Historic Stone and Marble Restoration & Repair Services

Historic stone and marble are among the most enduring materials found in American architecture, from carved limestone columns and sandstone facades to marble floors, statues, memorials, and decorative stonework spanning nearly every style and period. Over time, even the most durable stone deteriorates: surfaces stain, joints fail, sections crack, and decorative carvings erode. When that happens, the work demands a specialist.

John Canning & Co. has decades of experience in historic stone restoration, conservation, and repair. Our skilled artisans and tradesmen work across the full range of stone restoration services from straightforward stone surface cleaning to complex structural repairs using carving, casting, filling, and Dutchman replacement.

Our stone restoration services are among the best in the industry due to our team of educated tradesmen. The reputation we’ve built is in our experience on resolving complex restoration issues through a variety of safe stone restoration methods and techniques compliant with ASTM standards for stone conservation, making us a good fit for projects of all difficulty levels. We often pride ourselves on being the “preservation problem solvers” who have the resources to accomplish any requests.

Testimonials

“Canning understands materials and specifications, especially traditional materials and techniques, and understands and appreciates the benefits of a truly collaborative effort in design excellence. [WV Capitol Dome]”

— ELIZABETH A. MOSS, LEED AP, ARCHITECTURAL CONSERVATOR, SWANKE HAYDEN CONNELL ARCHITECTS, NEW YORK CITY

“The project included extensive repairs to the Library’s crowning architectural feature, a vaulted Guastavino tile ceiling. Canning & Co. provided exceptional craftsmanship, meticulous project management, and the highest level of respect and care for the Museum’s special environment. The results were spectacular. We applaud Canning & Co for a truly inspirational level of commitment to excellence in historic preservation.”

—DONNA D. CURTIN, PhD, EXECUTIVE DIRECTOR, PILGRIM HALL MUSEUM, PLYMOUTH, MASSACHUSETTS

“Canning’s craft and artistry take aspects of a design to absolute levels of refinement that bring new works to unexpected levels of delight. Visitors are amazed that such craft is still alive and well in our expedient world.”

— JOHN I. MEYER, AIA, MEYER & MEYER ARCHITECTURE AND INTERIORS, BOSTON, MASSACHUSETTS

“I have had the pleasure of working with artisans in many countries overseas. Canning truly ranks among the best in the world!”

— VIVEN P. WOOFTER, IIDA, CULTURAL HERITAGE OFFICER, OVERSEAS BUILDINGS OPERATIONS, US DEPARTMENT OF STATE

Our Process In Stone and Marble Restoration & Repair

Every stone restoration project is unique, but our approach follows a proven, structured process that ensures consistent, preservation-compliant results.

Step 1 — Investigation & Archival Research

Before any work begins, we research the history of the structure and the role its stone elements play within it. This typically starts with a historic stone analysis, a blend of on-site investigation and archival research to understand the original materials, construction methods, and any prior interventions. Simultaneously, we clarify project scope, budget, and stakeholder expectations to coordinate effectively with other trades from the start.

Step 2 — Structure Evaluation

Once the project is fully understood, we must evaluate the current structure in order to identify the type of stone used, stabilize the structure as necessary, document areas of stone deterioration or damage, test various cleaning solutions, and create an initial treatment proposal.

Step 3 — Stone Cleaning

Where cleaning is required, we always select the mildest solution capable of achieving the desired result without altering the stone's original color, texture, or surface integrity. Methods include hand-applied cleaning solutions using natural sponges, poultice treatments that draw impurities out of porous stone surfaces, and latex compound applications for highly detailed decorative elements. We never use aggressive methods that could cause irreversible damage.

This can be achieved through a number of best stone practices processes. A simpler course of action might be the application of a cleaning solution by hand using natural sponges. Other processes may include a variety of poultice methods designed to draw impurities out of the stone surface. For example, applying a latex (or other) compound to the surface encapsulates the debris and then pulls it away from the surface once dried. This method can be particularly effective on extremely detailed pieces. All of our techniques, however, ensure that no further damage or changes are made to the structure—retaining its integrity and color.

Step 4 — Stone Repair

When repair is needed, the specific method depends on the nature and extent of the damage. Common approaches include:

• Dutchman repairs, replacing damaged or deteriorated stone sections with precisely cut matching material, a traditional technique recognized in historic preservation practice
• Removal and resetting of existing stones
• Repointing, removing failed mortar from joints, and replacing it with new mortar matched to the original composition

Sourcing and installing matching stone; when original material is unavailable or cost-prohibitive, our craftsmen can replicate stone elements in scagliola or faux marble finishes.

Cost Factors in Historic Stone Restoration

Stone restoration costs vary from project to project. The key factors that drive pricing include:

• The type, condition, and rarity of the stone material
• The size, complexity, and overall scope of work
• Accessibility, particularly whether scaffolding, lifts, or specialty rigging is required
• Whether the underlying structural elements also need to be stabilized or repaired
• Scheduling requirements for public-facing buildings (business hours vs. off-hours work)

For a full breakdown of what drives restoration budgets, see our guide: 7 Things to Consider When Budgeting for Historic Stone Restoration. For a project-specific estimate, contact us directly. Every project is different, and an accurate assessment requires seeing the work firsthand.

SELECTED PROJECTS