Historic Plaster Conservation Services

The Global Standard for Conserving Historic Plaster

HPCS
  Historic Plaster Conservation Services
  Applied Science

Our knowledge and expertise in historic plaster conservation allows us to provide problem-solving solutions for even the most complex projects.

John Canning & Co. uses not only its knowledge and experience but also state-of-the-art technology to repair structural problems in fragile historic buildings.  As one of the few official installers for HPCS (Historic Plaster Conservation Services) we have access to a suite of products to use as additional tools on consolidation and fragile plaster projects.  John Canning & Co. implements the advanced technology of HPCS to save old plaster by addressing the problem at its root- where the plaster meets its substrate.

Plaster Consolidation is the long-term solution to the plaster problems that historic structures often encounter.  The HPCS treatment method dramatically strengthens and adheres plaster to its substrate, leaving the ceiling strong and maintenance free for a long time.  This HPCS treatment method of "plaster consolidation" effectively converts plaster and wood lath into a single unified system. 

John Canning & Co. can handle all stages of historic plaster conservation including plaster condition surveys/assessments, stabilization & reinforcement of fibrous plaster panels/coffers, plaster on masonry, consolidation of plaster on wood or wire lath, plaster restoration & stabilization as well as ornamental, flat, and acoustic plaster -restoration & replication.

Historic Plaster Conservation Services for each Stage of the Project

PLASTER CONDITIONS SURVEY

STABILIZATION & REINFORCEMENT OF FIBROUS PLASTER PANELS/COFFERS

CONSOLIDATION OF PLASTER ON WOOD LATH

PLASTER RESTORATION & STABILIZATION 

ORNAMENTAL, FLAT, AND ACOUSTIC PLASTER - RESTORATION & REPLICATION

 

HPCS PLASTER CONSERVATION PRODUCTS

 

Plaster Conservation Products

Tri-Funori
HPCS AD25
HPCS
HPCS CO
HPCS GR
HPCS
HPCS Re
HPCS En
HPCS

Case Study

Saint Agnes Parish, Reading MA

John Canning Co. was brought in to perform plaster stabilization of the ceilings at the nave, aisles, and sanctuary.

John Canning Co. started this plaster stabilization project by setting up temporary access, lighting and safety equipment.  After removal of broken plaster keys, plaster consolidate was applied to the wood lath from the attic space. Acrylic grout/caulk was injected/applied to reconnect plaster to the wood lath. Missing keys were recreated with grout/caulk and where required wood lath was reattached to furring with reinforced caulk.   In addition to the above ceiling ribs were mechanically fastened to the wood structure. A combination of the HPCS Co Consolidants and Ad Adhesive products were used for this project.

1887

Year Built

4

Products Used

9,500

Square Feet

St Agnes

Download a Copy of Our Brochure

Download a free copy of our brochure to learn more about each of the services provided by John Canning & Co.

It has been my pleasure to work with the John Canning Co. for over 15 years. Their talent and skill in execution is unique in the arena of historic restoration projects.

MICHAEL A. MACDONALD
DIRECTOR OF BUSINESS DEVELOPMENT, DOWNES CONSTRUCTION COMPANY, NEW BRITAIN, CONNECTICUT

Frequently Asked Questions

The HPCS conservation treatment technology strengthens original plaster in place and greatly extends the useful service life of the plaster.  We treat the entire plaster ceiling system as a whole. Other contractors use mechanical fasteners and spot injections that provide little more than a temporary fix.

The HPCS treatment method has been used for over the past 30 years.  The HPCS treatment method has been used to consolidate more than 100 ceilings in important buildings in the United States and Canada.

Yes, HPCS has developed a roster of plaster conservation products that not only consolidate plaster systems but address every conceivable challenge that fragile plaster presents.

There are many HPCS projects that are 25 - 35 years old and have never had a failure of any kind. In two specific cases we know the HPCS consolidated ceilings have survived severe water infiltration from roof leaks without any structural ill-effects. In short, we know of no reason to doubt that an HPCS consolidated ceiling will perform well for a hundred years or more.

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