Prefabrication is by no means a new idea, but in the past, unimaginative uniformity in design, together with limited materials, led to natural distaste for this form of construction. Recent years, however, have produced a revolution in this field, as a result of new techniques, wider ranges of materials and a far more variety in the shapes and sizes of prefabricated units. In fact, nowadays, there remains very little in the world of building and civil engineering that cannot be constructed effectively and attractively by means of prefabricated units.
预制结构并非新构想，但是在过去，由于在设计上严重缺乏统一规格，再加上 材料有限，自然就使得这种施工方式不受欢迎。然而近年来，由于新技术的出现，材料 的选择范围更加广泛，以及预制构件的形状、型号多种多样，致使这一领域发生了一场革命。事实上，在今天的工业与民用建筑中，几乎所有的施工都能采用预制构件达到高 效而完美的效果。
Generally speaking, prefabricated construction in relation to building is divided into two classes. Where the prefabricated units are entirely or almost entirely produced in a factory and transported to the site, the method of construction is known as factory industrialized building or system building. On the other hand, if the component parts are mainly produced by the contractor in a yard adjacent to the site, it is known as on-site industrialized building.
-般来说，与建筑物相关的预制装配式结构分为两种。若预制构件完全或几乎 完全由工厂生产，并被运到施工现场，这种施工方式就是工业化建筑方式，或称为系统 建筑方式。另一方面，如果组装构件主要是由承包人在施工现场附近的场地制作出来的，这种方法被称为现场工业化建筑。
Many large building contractors have developed their own organizations of system building for houses and flats, and have often been successful in securing contracts in direct competition with traditional building.
The main advantage of factory industrialized building is that the prefabrication units can be produced to a very high standard of precision and a consistently high quality. Consequently, the tolerance margins, which are so necessary in traditional building methods, can be greatly reduced. Of course, careful planning and diligent supervision by the designer, together with the utmost standardization, are essential to attain these objectives. The working conditions in a factory are far more amenable than those on a site, and this permits continuous production. Since unskilled labor is mainly employed in the production of the units, construction should prove to be less costly.
To gain the maximum advantage from this system, there must always be clear liaison between the factory and site organizations. The units should be delivered precisely when they are required and site manpower and plant should be ready to incorporate them into the construction on their arrival. The failure of proper co-ordination only results in unnecessary delay, which defeats the principle object of this method.