Industrial Waterproofing and Masonry Facade Restoration at Merrill's Wharf

History
In 1884, the first structure of the present 100,000 SF Twitchell-Champlin Company building on Merrill Wharf in Portland, ME was constructed. After that, four more additions were added in 1886, 1896, 1904 & 1914-1924. It is the largest masonry structure built on the wharf, and was one of the last to not be used for industrial purposes. The building remained unaltered for 50 years until it was rehabilitated in 2011. This building holds significant historical value for the city of Portland, not only because it was one of the few buildings built in the 19th century to survive the great Portland fire, but also because it is located across from the Portland Waterfront Historic District. For these reasons, the owners requested that the boundaries of the Portland Waterfront Historic District be expanded to include this structure.

The property retains a high degree of desirability in regards to location, setting, design, feeling and integrity of materials and workmanship, which are in line with the Portland Historic District. Spanning more than 30 acres, the Historic District includes architecture examples of Federal, Greek Revival, Gothic Revival, Italianate, Second Empire, Romanesque Revival, and Queen Anne. Over the years, the building had been significantly neglected. The windows had been in-filled with concrete block, the roof was structurally unsound and leaking, many of the floors were sagging, and the exterior brick masonry façade was in desperate need of restoration to prevent sections of the walls from falling down.

Project Overview
One of the major issues with the structure was the separation of the outer course of brick from the inner wythes. Each year the freeze and thaw from water infiltration caused header bricks to breakdown, and also caused sections of the walls to bulge. Several sections of wall had previously fallen down and were rebuilt using brick and mortar that were incorrect in size and strength as well as historically incorrect.

Metric Construction awarded the masonry restoration and industrial waterproofing contract to Knowles Industrial Services of Gorham, ME. Becker Structural Engineers (BSE) provided plans, specifications and construction monitoring for this technically challenging project. The owner also hired a masonry expert, Building Envelope Consultants (BEC), to help Becker with some of the details as well as to monitor the quality of our work. Throughout the project, the Maine Historical Preservation and the National Parks Historic Preservation Societies became involved to help minimize changes to the construction techniques that were used during the original construction. Both entities required the use of original material types and installation practices in order to preserve the historic look of the building, which would in turn result in tax breaks for the owner.

Initial Efforts, Challenges & Concerns
During this project, all of the windows in the entire building were replaced with new energy efficient units. A completely new roof system was also installed. In addition, the GC was undertaking a full interior gutting and rebuilding of the top four floors to provide new office space for the legal firm of Pierce Atwood. These items of work were performed by other contractors hired directly by the GC. Complications and concerns included staging and scaffolding erection. Since the building is adjacent to the ocean, we were faced with nearly constant high winds and Winter construction required supplemental heat to protect the new masonry work from the freezing temperatures. During the project, unanticipated conditions arose as crews started removing deteriorated bricks. Some of these included completely deteriorated interior wythe mortar that had turned to sand, broken granite sills, and internal cracking caused by building movement during the construction process. Knowles worked closely with the owner, GC, BSE and BEC to provide practical restoration solutions and actually save the owner money on the overall project using some of the design changes we developed.

Innovation in Construction Techniques and Materials
Early on the project it was clear that the overall repointing and rebuilding of brick on a structure of this magnitude would make for a one of a kind project. The strengthening of the building cracks was performed using an innovative system of Helifix crack stitching stainless steel helical rods and epoxy paste, and cellular foam cement was used to grout the voids between the outer and inner wythe of brick.

Contribution to the Community

What has been described recently by some as an eyesore on the waterfront of Portland is once again a beautiful historic landmark contributing to the revitalization of Portland’s waterfront, as evidenced by recent stories in the Portland Press Herald (see attached articles highlighting how the renovated building is attracting business to Commercial Street). This was one of the last buildings in need of a facelift in order to compliment and improve the look of the Portland waterfront. The owners and neighbors are now proud of the building instead of having to apologize for it. Since the completion, the selling market for the remaining space has been high with most of the first floor now occupied.

The fishing fleet also enjoyed the benefit of new pier pilings, electrical hookup, lighting, water source and dedicated parking for their usage. It was very important for all involved to keep the maritime community intact and help improve the marine infrastructure while improving the adjacent building property for the new clients. Keeping Pierce Atwood in Portland was also a huge benefit to the city and community because it offered employment opportunities and a tax base that would stay in the city.