Dorothy Lawrence

Dorothy possesses one of the finest minds in the industry. Her wisdom and sage advice over the years has been beneficial to scores of architects - including Frank Lloyd Wright - engineers, owners and Division 7 contractors. Her meeting with Frank Lloyd Wright during the construction of the Guggenheim in New York City (one of his most famous projects) in the late 1950s was quite memorable. Her waterproofing materials were applied on the below-grade sections of the building. When they met at the project meeting, Wright insisted that Dorothy remove her high-heel shoes since she was taller than he was. "He was an amazing man. But he could be difficult to work with," she says. "For instance, he felt that concrete waterproofs itself. This is an opinion that I do not share."

Mies van der Rohe was another famous architect with whom Dorothy has worked. Her waterproofing material is applied on three of his projects in Chicago including his famous 860 and 880 Lakeshore Drive high-rise designs, which were completed in the early 1980s. Over the past 50 years, Dorothy's roofing and waterproofing systems have been applied on a plethora of identifiable buildings, including the John Hancock Building in Chicago, the Empire State Building in New York, and at numerous airports and hospitals throughout the country. Dorothy was intimately involved with most of these projects and can still recite many of the most intricate details of each one. "I had to be present on these sites during construction because I was a woman material manufacturer and at that time I could not afford to have a problem," she explains.

Plaza waterproofing.

Earning Respect

Dorothy began working part-time during the summers in the accounting department, but it was not long before her insatiable curiosity took over. "Father had three daughters and had long given up the idea of having a son to take over his business," she explained. Fortunately, Dorothy, his oldest daughter, admits to being somewhat of a tom-boy and as she continued to work for the company, she grew to like the industry.

Dorothy would often leave the office to help load trucks and assemble materials and equipment for the projects. Her responsibilities grew and she eventually became a project manager, a position that provided her the opportunity to gain first-hand experience with actual field conditions.

Of course, her presence on the roofs was quite an anomaly in the 40s. "My father tried to keep the boys in line and told them not to curse in my presence, but I still heard all of the whistling and cute remarks," she recounts. "I would blow a kiss to the boys with the most clever lines." The men quickly found that her beauty was equally matched by her intelligence and determination. "I think I gained their respect the first time I jumped into a tractor trailer truck - in a skirt - and successfully backed the flatbed into position."

Upon her graduation from Ohio Wesleyan University in 1946 with a B.A. and minor in chemistry, Dorothy turned her attention to product development. Her first product - developed in 1946 - was "Glasfab," which is a woven glass fabric for roofing and waterproofing applications. The material was designed using a "yellow jacket" white resin, asphalt and coal tar pitch. It was developed in compliance with ASTM D 1668 and Federal Specification No. HH-C-466 a and b. She sold the Glasfab technology to Koppers Co. in 1966. The weave and coatings developed for this product are still used today.

While working as manager for the Lexington Supply Co. (founded by her father in 1944), Dorothy developed the design for the original "Lexsuco" insulation clip in 1948. She sold the clip technology and the company to Lexsuco in 1951.

She also designed and developed the first hot bitumen roofing tankers and systems for pumping and handling hot asphalt and coal tar pitch to the roof areas. Much of this technology is still used today.

Dorothy married Jack C. Lawrence in 1949 and the next year they formed the Twinsburg-Miller Corp. Twinsburg-Miller, or TWIN-MILL as it was known, manufactured and sold roofing and waterproofing products such as Glasfab to roofing and waterproofing contractors and distributors. When they sold the Glasfab technology to Koppers in 1966, Jack went to work for Koppers as Technical Director. At that time, Dorothy formed the Laurent Corp., which is still in the business of manufacturing and marketing Laurenco Waterproofing Systems and Laurenco Roofing Systems, in addition to private-label fabrics (glass, cotton, jute and polyester), felts (polyester and glass) and various coatings and adhesives for others serving the roofing and waterproofing industry.

Jack passed away in 1971 and Dorothy has continued to run a highly successful company while raising their two children, Caroline and Jonathan. Under Dorothy's strong guidance, the company has prospered despite economic setbacks, male bias, and a fire that destroyed the manufacturing plant in the early 1990s.

Jonathan Lawrence began work at Laurenco on a part time basis in 1977 and has worked full time since 1983. He has worked closely with his mother in product development and technical duties, and in 1994 he designed all of the present computerized manufacturing equipment in their Leavittsburg, Ohio, plant. Jonathan has also taken on the additional duties of project field inspections due to Dorothy's limited mobility on construction sites. However, if you send an as-built detail to Dorothy, she will happily chat you up on the phone and convey her comments, as she is still in the office every day.

Recognitions and Awards

Dorothy has also been a member of the American Concrete Institute since 1976. She served as chairman of Committee 515: Coatings from March 1986 through March 1990. She cites ACI and the Portland Cement Association as excellent sources of information regarding the study of concrete technology, which is particularly important in waterproofing applications. Dorothy said, "It is like the line in that old Protestant hymn, ‘You build your faith on rock, not sand.'"

Over the years she has also been a featured speaker for many industry associations and organizations, imparting her great knowledge on topics ranging from roofing and waterproofing design and material technology to "Waterproofing Nuclear and Fossil Fueled Generating Plants." Dorothy was well versed on the nuclear plant topic, since at the time in this country's history when we were still building nuclear plants, Laurenco was the only product commissioned to waterproof these highly sensitive structures. This is further testament to Dorothy's product development and technical capabilities because these structures absolutely cannot leak. These are also the projects that she looks back on with great personal satisfaction because of the technical challenges that they presented.

Sage Advice

Her background, experience and expertise are impressive regardless of the fact that she is a woman in an industry that is still male-dominated. She has managed to climb to the highest points in this industry in expertise and respect despite the objections of some men. She does not consider herself as a pioneer for women in this industry, but she is. When asked how the role of women in the industry has changed over the years, she quickly responded, "It is much nicer now and generally women are more accepted on construction sites."

Dorothy does not believe that gender should provide any undue privileges and cautions: A woman must still perform to be effective. "If a woman is capable of completing the task at hand, use her. If she is not capable, get her out the way. Of course, this is true of both men and women. If you get into this business you must know what you are doing."

Her advice to roofing and waterproofing contractors is also straightforward. She strongly believes that the key to a company's success is based on the skill level and quality of the crews. "When I worked for my father we had a key group of men that were good workers who could also be effective foremen," she explains. "We built crews around these men in the busier months and we combined them as a crew in the slower months. They worked year round and they stayed loyal to us for many years." Dorothy believes that intelligent foremen and superintendents are the key to a company's success: "Superintendents that work in the field are now rare birds." She feels that successful crews are made up of people that can be trained to do repetitive work at a consistently high quality.

She also feels that the best companies maintain their key personnel and do not get in the habit of hiring workers from the union halls on an as-needed, project-to-project basis because this does not build a long-term workforce. "When we look at potential applicators for our roofing and waterproofing systems, I rarely look at the status of the company other than if they can pay their bills," she says. "I always look at the experience level of the foremen and crews, their experience with application of similar systems and materials and how long they have been with the company. After all, these are the people that are actually installing the material."

Dorothy feels that the trade unions can play a bigger role in training the workers that are the future of this industry. She says, "The most important issue that I would like to see stressed in training is a discussion of why we complete details the way we do. If the applicator had a better understanding of why things are done a certain way, the overall effort would improve." In this regard, she feels that properly trained workers will be more effective and remain in the profession for the duration of their careers. These applicators could also help train the next generation of applicators. Dorothy remembers the way application techniques were passed along by the older generations. "On-the-job training by qualified journeymen to apprentices was the way that these trades were advanced for generations."

Dorothy also believes that "pride of equipment leads to pride in workmanship." She cringes when she arrives at a job site and sees dirty or broken-down equipment because it could give the false impression that the company is not committed to excellence. Her advice to contractors is to "maintain the equipment and clean the trucks prior to bringing them to the job site. Show the people that you are working for that you are proud of what you do. Always fix all broken equipment before it leaves the yard." The old adage that first impressions are lasting impressions holds true here.

Dorothy has also spent countless hours with architects, engineers and designers. Over the years, she has occasionally done some consulting work in the roofing and waterproofing industry giving appropriate design solutions on problems encountered by other manufacturers or design professionals. One issue that she has observed is that designers tend to design solutions that are one-sided and create other ancillary issues. She cites one below-grade waterproofing detail on a beam at grade in which the architect designed scuppers through the structural slab to allow for water run off. The slab was sloped to the scuppers, however, since the slab was located below grade, ground containments and debris plugged the scuppers and water was constantly ponded in this area. The final solution was to fill in the scuppers and waterproof the structural slab. Dorothy comments, "It does no good to solve one problem and create five others."

Material development and technology have been the lifeline of her career. In 1955 Dorothy attended Case Western Reserve University in Cleveland to supplement her education in chemistry and geology. These educational advancements proved to be beneficial as she was instrumental in developing cold process roofing and waterproofing materials. "The key to proper material development is that the developer must know what the materials do," she says. The biggest concerns she has regarding the material development industry at this time is that products are sales-driven and designed to solve only one problem. The technical people rarely go into the field to see how the materials perform in actual conditions.

In 1953, Dorothy designed the first waterproofing and roofing sheets to utilize rubber. These were the first modified bituminous systems. They were then manufactured with coal tar pitch and asphalt bases. In 1957, she modified the formulation for the only asphalt/synthetic rubber modifications that duplicated coal tar pitch. To this day, Laurenco products are manufactured in a similar manner. Dorothy still believes that cold process materials are the biggest advancements in this industry. After more than 50 years and millions of square feet of her applied roofing and waterproofing materials in some of the most critical facilities in the world, who is going to disagree with her?

In sum, Dorothy Lawrence has been directly responsible for some of the most important technological developments in the roofing and waterproofing industry. Her tireless effort over the past 60 years has been beneficial in the advancement of material technology and application techniques. Although she has been directly involved with some of the most famous projects and lists a litany of "firsts," her fondest achievement is that she has been able to help contractors succeed throughout the years. This is a testament of the true character of this phenomenal woman.

Side Bar: Not Just Another Pretty Face

A student at Georgian College in Barrie, Ontario, Michelle Ostergaard started her roofing career four years ago as a summer job working for her father, a subcontractor for Mac Tile Roofing. "When I was little I would go to work with my dad," she explains, so it seems only logical that she would help her dad out for real when she was old enough. He obliged by training her in bricklaying and tile.

When she's not on the roof, Ostergaard is studying hotel and resort operation. She will graduate this year, though she will probably continue working for Mac Tile for a year after she is done with school (to pay off school debt) and then move into her chosen field.

You may have noticed that Ostergaard is featured in some of Flexia's print ads. She will also appear in an instructional video for the company. According to Doug Ryan of Flexia Corp., Flexia's involvement with Mac Tile Roofing stems back 20 years. At the time, Jim McCormack, president of Mac Tile, was the general manager of Marley Roof Tile. This company, headquartered in England, was setting up a manufacturing facility in Milton, Ontario, and was accustomed to using synthetic underlayments. "Jim and his people worked closely with Flexia Corp. (Twinpak Inc.) in developing Tri-Flex 30," says Ryan. "Marley closed approximately five years ago and Jim opened up his own company with his son. They use Tri-Flex 30 today."

Ostergaard says that the new product, a UV-stabilized polypropylene roofing underlayment, is lighter to carry and easy to install. On a typical job, usually about 19 to 26 squares, she and another worker will follow behind her dad stapling as he lays down the roll. Mac Tile uses concrete tile products from UniCrete, Calgary, Alberta. The company has five crews.

"Using Michelle in our ad was just a coincidence. Our camera crew was at the site taking pictures for our new ad campaign and by chance Michelle happened to be on the crew doing that particular installation," explains Ryan. "We are also gathering footage for future use in films showing individual installation instruction for tile, slate, metal shingles, standing seam and asphalt shingles."

Of course, when you are a woman on the roof, you do tend to stand out. Ostergaard recalls that while working on a residential subdivision with a boardwalk in the front, people would stop and stare when they realized she was up there.

"People do look at you differently," she admits. "Then they say, ‘You do pretty good for a girl.'" She does do good work, of course, regardless of whether or not she is a girl. Her only limitations are in the amount of weight she can lift up to the roof.

No matter what, Ostergaard enjoys what she does. "I was sore at first, but your body gets used to it," she says. "Girls probably think that they can't do it. They can, but they can't be lazy." Her advice to other women is that roofing is similar to playing sports - you have to practice and put in the effort.

In the mean time, she believes that it shouldn't matter to people that she is a girl, but she accepts that it does, and it will, until they get used to it. --by Josephine A. DeLorenzo