Masonry Magazine March 1970 Page. 18
PREFABRICATION...
... is it the coming thing?
Due to the intense interest of those attending the recent MCAA Annual Convention on the subject, Prefabrication-Is It the Coming Thing?, we are reprinting condensed versions of the addresses by M. H. Allen and Marlin Miller, Jr.
In addition we are including the talk, The Need for Industrialization of the Masonry Process, presented by John A. Dawson, P.E., at the annual meeting of the Canadian Masonry Contractors Association in Edmonton, Alberta, February 6, 1970.
M. H. ALLEN
Director, Structural Research
Structural Clay Products Institute
McLean, Virginia
If we confine our thinking and discussion today to merely the prefabrication and erection of masonry wall panels, we will be overlooking the real problem that will be facing the masonry industry, as we know it, in the years to come. We must be thinking in terms of industrialized building systems, and how best our products and services can fit into that concept of building. Prefabrication is only a part of the industrialized building system concept, although, admittedly, it is a most important part.
The construction industry generally in this country, and the masonry industry in particular, have been slow to recognize and accept the need for being concerned with this trend in construction. Our European friends have been at it since not too long after World War II, when the combination of critical shortages in housing and skilled construction workers forced them to seek relatively quick solutions to the problem. It is our present so-called "housing crisis," coupled with an increasing concern with what some call a "disastrous shortage" of skilled craftsmen in the construction trades, that has caused us, likewise, to finally look at industrialized building systems as the ultimate answer to the problem.
Poor track record for cost savings
One deterrent in the past to a more ready acceptance of industrialized construction has been the somewhat poor track record of prefabrication with respect to savings in cost. The cost savings that many feel are inherent in prefabricated housing, for example, have never been actually realized. Even today in such European countries as Denmark, where a high percentage of brick manufacturers have developed and are producing prefabricated wall panel systems, it is difficult to find one who can claim that his system can be put in place at less cost than a comparable wall laid by hand on the job. Some European building systems claim cost reductions of 10 to 20 per cent. It is significant, however, that such savings are usually claimed for large-scale projects involving, often, thousands of housing units. It is felt by many authorities in this field that such savings are the result of better field organization of construction operations, made possible by such large-scale projects, rather than by the production techniques per se.
Even so, the industrialization of buildings in this country is the "coming thing" and is unavoidable. While it will be evolutionary rather than revolutionary, we must concern ourselves with this trend and prepare ourselves to participate in it. By evolutionary, I mean that during the next decade, at least, there will be a mixture of industrialized and conventional field construction techniques used. I doubt that, within the working lifetime of most of us today, we will see industrialized building systems completely replace present methods of on-site construction. It is even more likely that such will never happen.
Therefore, we may have more lead time than some would try to make us believe. However, we should not let that lull us into a false sense of security. Research and development take time and money, and the sooner we get started the better prepared we will be for getting our share of whatever industrialized building systems market eventually develops.
Long-range thinking, planning needed
This preparation must involve more than just developing an efficient and economical method of fabricating a good brick wall panel. Such an approach, if pursued no further, could relegate our product to merely a skin or curtain wall material too easily replaced with something else. On the principle that we must crawl before we walk, and walk before we run, this is the obvious starting point, but it should not be the end point.
I'm happy to say that at least one SCPI member currently deeply involved in an "industrialized building system" activity has not let himself fall into that trap. This company is thinking in terms of a building "package," so to speak, in which prefabricated brick masonry wall panels are the important vertical structural elements in the overall system which involves not only the exterior building shell, but the interior partitions and walls, finishes and mechanical systems.
Lest there be any misunderstanding, let me say here that I am not suggesting that, before a brick manufacturer or a mason contractor embarks on a program of developing a prefabricated wall panel system, he must be prepared to go all the way with a complete industrialized system incorporating all parts of the completed structure. What I am suggesting is that he must recognize that his panel system must be able to be integrated with other elements in a building system.
If the panel is to be a loadbearing element, it should be remembered that the general concept of the contemporary bearing wall is the combined structural action between floor and roof systems and the walls. Therefore the connections between floor and roof systems and wall systems are very important and must be designed to