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Robertson protected Metal Sheets

Few firms engaged in the manufacture of building materials have such a record of progress as have H. H. Robertson Co., Ellesmere Port, England, manufacturers of Robertson Protected Metal (“R.P.M.”) sheets and ventilators.

The policy of this company, since its inception, 25 years ago, has been to concentrate exclusively on the production of an inexpensive, permanent sheeting for the roofing and siding of commercial buildings. At the present day the H. H. Robertson Co. are operating large works in England. Canada and U.S.A., while branch offices and agencies are established in the main cities of the world.

R.P.M. sheets have the strength of galvanised steel sheets with none of their disadvantages. The annealed steel core of R.P.M. is enclosed under heat and pressure in a thick envelope of specially refined asphalte, which, in turn, is encased and bonded under pressure with a coat of heavy asbestos felt. The third and final treatment is the application of the tough waterproof sealing coat, which protects the sheet from mechanical abrasion and damage in fixing. The sheet steel core by reason of the three distinct sealing coats, is absolutely protected against corrosion under the most severe conditions obtainable.

The New Zealand Railways Department use R.P.N. extensively for covering the large structures housing the Department's rolling stock and machinery.

Ten years ago the H. H. Robertson Company commenced the study of ventilation in commercial buildings. Experiments and tests were carried out for a period of three years, during which time over fifty different types of ventilators were tested under working conditions.

A feature of the Robertson ventilator, is the patent suction band which enables the ventilator to exhaust at full capacity, irrespective of the direction of the wind. Moving parts, liable to choke and stop the action of the ventilator, have been entirely eliminated, making installation a very simple matter, requiring no expert supervision.