Roof Spec Inc.

Project Profiles

The Basilica of Saint Mary, Minneapolis, Minnesota
The Governor's Ceremonial Mansion, St. Paul, Minnesota
The James J. Hill House, St. Paul, Minnesota
The Saint Paul Cathedral, St. Paul, Minnesota
Plaza VII Office Tower, Minneapolis, Minnesota
Wells College, Aurora, New York

The Basilica of Saint Mary
Minneapolis, MN

Project Services:

Development of detail drawings to facilitate the restoration and refabrication of the copper roof assembly; creation of technical specification and project management.

Project Highlights:

The Basilica of St. Mary was built in 1912. Its copper roof was expected to last 100 years, but after 80 years it needed a complete overhaul. The copper roof replacement had to match the original design and intent of the historic structure as closely as possible.

Roof Spec developed detailed drawings to facilitate the restoration and refabrication of the copper roof assembly; developed technical specifications and acted as on-site representative to the Basilica's committee concerning not only the roofing but also installation of the domes and components, drainage, insulation and ventilation which would impact the 100 year performance design criteria.

"In total," explained project manager Verl Schmeichel, "the project involved 500 squares (or 50,000 square feet) of roof. There are upper and lower naves, the transept, apses (small half-circle and quarter-circle areas along the lower level) and the dome.

"Reroofing the dome was a unique challenge," explained Schmeichel. "It involved adding two layers of new plywood over the old dome to create a sound substrate to which the new roofing materials were attached. The inner and the outer dome are separate entities with a chimney effect to provide adequate ventilation."

Adequate ventilation was one of the old roof's major flaws. The temperature and weather extremes in Minnesota required special consideration. During the project, previously unknown voids were uncovered. The voids allowed water and cool air to enter the structure in unwanted areas, resulting in ice damming, freezing and splitting. The result was deterioration and disfigurement in many areas which Roof Spec helped to address. Now, with Roof Spec's assistance. the Basilica's goal of a roof system with a 100 year life cycle has been achieved.

return to top of page

The Governor's Ceremonial Mansion
St. Paul, Minnesota

return to top of page

The James J. Hill House
St. Paul, Minnesota

Roof Spec is just beginning work on the historic Hill House in St. Paul. The house, built by James J. Hill, was completed in 1891. Hill's fortune was built on his ownership in the Great Northern Railway and his many other pursuits including coal and iron ore mining, shipping, banking and finance, agriculture and milling.

His mansion was the largest, most expensive home in Minnesota. It contained 36,000 square feet on five floors including 13 bathrooms, 22 fireplaces, 16 crystal chandeliers, a two-story sky lit art gallery, and a 100-foot reception area featuring a profusion of elaborately carved oak and mahogany woodwork. Sophisticated technical systems in the home provided central heating, gas and electric lighting, plumbing, ventilation, security and communication. The final cost totaled $931,275.01 including construction, furnishing and landscaping for the three-acre estate.

Hill was very fussy about his home and who worked on it. He rejected stained-glass window designs by Tiffany and Company, saying they were "anything but what I want," and even replacing the architects when they ignored his orders to the stonecutters.

No doubt he would be pleased to know that Roof Spec has been retained to address ice-damming issues that pose a serious threat to the building now owned by the Minnesota Historical Society and recognized as a National Historic Landmark.

"We are just starting the evaluation process. When that is completed, we will begin the design portion, which will require that we maintain the building's historical correctness while incorporating state-of-the-art technology," remarks Roof Spec. "We will blend old-world, traditional look with 21st century engineering knowledge."

The project could take many years. Roof Spec is working on the project with the architectural firm of Miller Dunwiddie Associates.

return to top of page

The Saint Paul Cathedral
St. Paul, Minnesota

Built in the early 1900s, The Cathedral of Saint Paul is constructed in the Classical Renaissance style of architecture. It's crowning glory is it's stunning, copper clad dome accentuated by a cross visible to most of the city of St. Paul

RSI provided engineering, consulting and construction observation services for the restoration of the Cathedral of Saint Paul. Our Scope of Work included the redesign and replacement of the entire roof, including the copper dome, transept, apses, sacristy and various flat roof sections.

The new substrate for the dome was constructed as follows:

Two layers of 3/4" marine grade plywood secured with self tapping screws;
An initial layer of 40 mil self-adhering membrane (ice and water shield) applied for temporary protection;
An additional two plies of number 30 organic finishing felt (ASTM:D-226 Type II);
Prior to the installation of the new copper, a PyroKure 600 fire-retardant paper was installed to act as a slip sheet.

Much of the dome's exterior skin consisted of interlocking copper panels. As the interlocking sections approached the base of the lantern, the copper changed into a Bermuda-style panel. As the skin was replaced, the architectural copper sections that had been removed for restoration and repairs were reinstalled.

Cathedral Restoration Details

The copper columns are filled with over 28,000 board feet of polyurethane foam.
The restoration used over 1,500 pounds of solder.
The dome consists of 100,000 pounds of copper.
There are 42 miles of mortar joint repair.
Over 2000 rolls of ice and water shield and 30-lb. felt were used.
Over 1000 rolls of PyroKure 600 and/or red rosin sheet were used.

return to top of page

Plaza VII Office Tower
Minneapolis, Minnesota

Plaza VII Office Tower is a prestigious office facility located in the heart of downtown Minneapolis. The building was built in 1987, is 475 ft. tall, and consists of 37 stories of quality office space. The owner, Carlson Real Estate Company, is one of the top rated property management firms in the country.

On a yearly basis, Roof Spec, Inc. performs roof evaluations of all Plaza VII roof levels. Each roof assembly is evaluated to identify any deficiencies. Recommendations based on the condition of the roof assemblies, with budget forecasts for maintenance or replacement, are then supplied to the owner.

In 1998 and 1999, Roof Spec was instrumental in the design and construction administration of the 35th and 37th floor roof assemblies which total an approximate area of 14,000 sq.ft. The roof system designed and installed was a fully adhered EPDM roof membrane.

When asked to design the new roof assembly, we had to combat a long standing problem of high internal building pressure. This issue appeared to be the cause of the previous roof failure. To overcome the concern, we incorporated multiple functional layers into the roof system. After removal of the existing roof down to the poured in place concrete deck, we specified that a self adhering membrane be installed at the joint between the deck and the wall. A 1/2" Dens-deck was fastened to the concrete deck. One ply of self adhering membrane was installed continuously over the Dens-deck. The combination of Dens-deck and self adhering membrane provided a "pressure barrier" to eliminate the potential of "billowing" or detachment as had previously occurred. This was followed by the tapered isocyanurate insulation and a 5/8" thick OSB which was mechanically fastened to meet FM 1-120 requirements. A 60 mil EPDM membrane was then fully adhered.

Due to the tenant's extreme sensitivity to noise, all roofing work was accomplished during the night. To accomplish this, the contractor had to incorporate several light stands placed throughout the roof area to sufficiently view the work in progress.

Another hurdle that had to be overcome was removal of the existing roof debris. The facility was too tall to crane any material, so it all had to go through the building interior. Through coordination between Carlson Real Estate, Roof Spec, Inc., and the roofing contractor, we were able to protect the building interior on a nightly basis. Removal was performed every night without exception and the efficiency of the roof project was not compromised.

All of these factors, and the incorporation of a sound roof assembly design, led to a successful project completion. All parties involved in this project benefitted from proper planning and timely coordination to yield an effective roof system.

return to top of page

Main Hall
Wells College
Aurora, New York


Roof Spec's New York Office completed an almost $1 Million renovation project at Wells College in September 2001. The project took three years to complete because work was only performed during summer break due to its use as a dormitory.

Wells College is a small, well-respected private women's college in Aurora, New York. Main Hall was built in the late 1800s and houses dormitory, class and conference rooms. It is the centerpiece facility for the college and the site of various activities.

Main Hall's original roof was slate, but in the late 1970s a shingle roof was installed. During the initial design stage the college did not have the funds to re-roof with slate. Roof Spec specified an aesthetically suitable shingle system. During the bidding, a generous donation from an alumnus provided funds specifically for the purpose of re-roofing with slate to preserve the historic significance of the facility. Roof Spec, within a week, was able to revise the specifications and details for the installation of the slate.

Roof Spec wanted to design a roof that would provide a minimum of 50 years of service. The greatest cost involved in the project was access to the roof area and staging on the roof itself. The building is three and one half stories tall with a steep slope 12/12 pitch roof. Scaffolding alone had a cost of over $120,000. There was also 2,000 square feet of asbestos containing low slope roofing to be replaced.The dormers and breezeway roofs, approximately 2,200 square feet, were completed with flat seam lead-coated copper.

"Working on such a steep roof is slow and costly. These are costs that would be incurred whether it was a shingle or slate roof. It was our goal to design into the roof system the longest service life we could within the budgets available to avoid duplicating this cost to the owner as long as possible," said Roof Spec's Elmira, New York Office.

The installer was CFE of Elmira, New York.

return to top of page