Of all modern building techniques, the arch or portal frame seems the most naturally adapted to the average requirements for church design. Whether it be timber, steel or concrete, this form of structure gives a clean uninterrupted line to the interior of the church. Truss construction, with its inevitable angular product presents the age-old problem of ideal proportioning and tends to present a chillier, more austere interior, Furthermore, in order to achieve a psychologically satisfying auditorium, the rectangular form more often than not dictates proportionately greater height than arch construction, and consequently higher cost per square foot. The structure has to be expressed truthfully, not built into fake columns and brick piers. Like that of the theatre the church enclosure is used as a setting for a highly personal and usually emotional reaction on the part of the audience.
Visual stimulation is one of the most important design elements.
Structure, colour and the handling of light appears to be its chief components. The creators of the great Gothic churches were well aware of the psychological impact on the congregation when they introduced colour into churches. Even by present day standards, luminous colours can be an extremely moving design element, and therefore leads many to question the obsolescence of stained glass. There is no need however, to use elaborate stained glass windows, as economical coloured glass is available. White light is the most ticklish of all to handle as it has little or no emotional or symbolic content.