Coal Tar Pitch Roofing Handbook - 1896 - Pages 33 and 34
THE general use of Coal Tar Pitch and Tarred Felt for waterproofing cellars, foundation walls, vault arches, tunnels and underground structures generally, is of more recent origin than for roofing. Thirty years ago it was the exception to waterproof foundations while today it is the rule.
Within our experience, we have had opportunity and occasion to watch the growth and development of this important branch of the building industry, and to note the results of the various experiments which have been made with "asphalts" and other materials for this important work.
About 1872, the tunnel of the N. Y. C. & H. R. R. R. Co. above the Grand Central Station in New York City was built and waterproofed with Coal Tar Pitch and Tarred Felt with less materials and skill than is employed in similar work at the present time. A few months ago, work on the new terminal improvements for the Company now in progress, necessitated the demolition of the south end of the old tunnel, unearthing some of this thirty-three year old waterproofing, which can now be seen by anyone interested and which will be found to be absolutely unchanged in its waterproofing qualities.
- 33 -
LEADING Architects, Engineers and Waterproofing Contractors who have had occasion to note all that has been accomplished to date in this line, consider Coal Tar Pitch and Tarred Felt the standard materials for underground work for the simple reason that they have no equal in point of durability and economy for this important purpose, notwithstanding that each year brings its new crop of alleged improvements claiming to be better.
While we give no general specification for the application of Coal Tar Pitch and Tarred Felt for Waterproofing, for reasons which follow, we will state that even more important than in roofing is the employment of a waterproofing contractor whose experience and reputation for intelligent and honest work is assured. The mistakes of faulty waterproofing of underground construction are costly to rectify, particularly if a known water pressure is to be permanently resisted.
- 34 -