If he could come back to life, 19th century industrialist Isaac Buchanan might not be too happy to see the condition of the garden walls which wind their way through his historic Auchmar Estate in Hamilton, Ont.
But, he would probably appreciate the efforts now underway to restore at least a portion of it.
Located on Hamilton Mountain directly across from Mohawk College, the four-hectare estate was the home of Buchanan, described by a City of Hamilton heritage report as "a leading Canadian merchant, political figure, and civic leader."
Extending approximately 356 metres (1,167 feet) through the property, the 48-metre-high (12-foot-high) stone walls lead to a two-storey manor house which was built in 1855 at the same time as the walls.
Despite many repairs over the decades, the walls are in a state of partial collapse, says Peter Stewart, a principal at Toronto-based George Robb Architect.
Now, however, a first phase restoration is proceeding and it’s expected to provide some solutions for restoring the entire wall, he says.
The $800,000 restoration of a 40-metre-long (131-foot) section at the south end of the property closest to public view began in June. Brantford-based Robertson Restoration is the general contractor and Ojdrovic Enginering Inc. is the structural engineer.
"This (the wall) significant cultural heritage resource is protected by an easement with the Ontario Heritage Trust and must be conserved," says Stewart.
A few years ago the deterioration reached the point that a security fence was erected in front of the walls to protect the public and avoid liability. The City of Hamilton, which first acquired the property in 1999, has conducted a number of engineering and landscape studies and even proposed a temporary dismantling of the walls a short-term solution.
"The Ontario Heritage Trust was having none of that (dismantling)."
In 2011 George Robb Architect was hired to evaluate a number of restoration methods based on those earlier studies (including one by Ojdrovic Engineering). The work now being conducted by the contractor is a test case to evaluate those conservation strategies, says Stewart.
Although Robertson Restoration is only dealing with a small stretch, this phase is actually divided into four distinct segments—although the work is being conducted more or less concurrently, he explains.
Shortly after arriving on site, the contractor labelled, dismantled, and moved the arches, columns, and other supporting stones of a carriage gate and two adjacent pedestrian gates so new footings could be built. Only about 50 per cent of the stones can be reused to rebuild the gates.
"But the contractor has been able to obtain new stone from a quarry in Owen Sound which is a perfect match."
A complete rebuild of a second section is required, while a third fairly stable piece is being stabilized with new concrete buttresses. "They won’t be out of character as buttresses have been used on parts of the wall."
On the last section, the contractor is utilizing custom designed Cintec anchors on a length of the most plumb wall. Overdrilled vertical holes will be cored through the depth of the wall into the foundation. The overdrilling allows stainless steel reinforcing to be installed from above in one piece, while the proprietary anchors are encased in a sock which is filled with grout after insertion into the wall. "As the grouted sock expands during grouting, it fills the irregularities over the height of the anchor and bonds to the existing masonry."
Although the contractor will be finished this fall, the project won’t be technically complete. An assessment of the masonry strategies will have to be conducted by George Robb Architect and a report submitted to the city, says Stewart.