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Technically Speaking

One of the purposes of the Demonstration House was to explain to students contemporary methods of building. In most aspects, therefore, the construction system and materials used are in accordance with typical New Zealand practice. Several significant variations from these standards require some explanation.

The house has a concrete floor. This is reinforced with a steel mesh and poured over well-consolidated filling. It is surfaced with asphalt tile, and in the living-room, carpet over insulating board. This construction permits access from the house to the patio down only one step. Under-floor draughts are eliminated and the surfacing gives a warm and resilient finish. The problems of foundation dampness and vermin do not arise, and, what was important in this case, many additional yards of excavation were avoided.

With the exception of those opening on to the the patio, most of the windows are formed of sheet glass fixed directly into the frame, without the normal sash. Ample ventilation is provided through a solid pivoted panel over the windows. It is difficult to weatherproof a conventional type of window in such an exposed location. The system used allows controlled ventilation with complete weather resistance, and gives a larger uninterrupted area of glass.

The choice of a flat roof raises further questions of weather resistance. Provided that the initial installation is well done, and that the owner realises the importance of maintenance, this type of roof is quite satisfactory. By eliminating a parapet, and by dishing the roof to form its own gutter, the two major trouble points in flat roof construction have been avoided. Structurally a flat roof enables large economies in framing timber, is far more simply constructed and provides less earthquake risk than a tiled roof. From the designer s point of view it allows much more freedom in planning.

All the framing timber, and the exterior sheathing, is insignis pine treated against borer before erection. With the dwindling supply of native timbers, the use of exotic timbers of this type will become increasingly necessary. Insignis pine is light, easily worked, and has adequate strength for domestic construction. The panelling in the utility room shows that it is suitable for dressed surfaces.

The living-room fireplace differs from normal in that the flue is exposed to the room. It is constructed of steel plate with brick flue liners, and lagged with mineral insulation. This will permit a comfortable amount of radiation and consequent reduction in heat loss, together with improved draught.