Houses of the 1940s-60s typically had fairly small timber casement windows.

Typical 1940s-1950s houses had fairly small, multi-paned, timber-framed casement windows. Though aluminium windows were available from the late 1950s they were expensive and only rarely used.

Architect-designed houses tended to have larger areas of glazing.

Original details

Windows of the 1940s consisted almost entirely of two types. Units could be 54 x 24” (1350 x 600 mm), three-pane casements, or 39 x 24” (990 x 600 mm), two-pane casements (Figure 3).

Some were full side-opening casements, some were split-rail construction with a fixed bottom section and a top-hinged opening sash (Figure 4), and some were fully-fixed sashes.

Except for the toilet and bathroom, which were fitted with opaque glass, glazing typically consisted of 22 x 16” (550 x 400 mm) clear glass. Head flashings became standard over windows and doors.


Living rooms and bedrooms generally had three or four, three-pane units in a combination of fixed and opening casement sashes often combined using a split rail with an awning toplight.

Kitchen windows were generally made up of three or four, two-pane units, also in a combination of fixed and opening sashes with some  top hung or awning opening sashes.

The bathroom and laundry generally had a two-pane single or double unit consisting of a toplight and  a casement (side-opening) sash.

Sashes and frames

Sashes and frames were timber, generally rimu, redwood or western red cedar, but other native timbers such as miro and totara may also have been used early in the period. They were typically faced on the exterior with 4 x 1” (100 x 25 mm) facing boards (Figures 5 and 6).


Over the period the size of windows increased and the window elevations changed but timber remained the predominant material. A wider range of hardware for timber sashes became available.

Aluminium and steel windows

Anodised aluminium windows and louvred windows were available from the 1950s. However, aluminium windows were more expensive than timber frame windows they were not commonly installed.

Steel windows which had been available since the 1930s were sometimes used in buildings of the late 1950s and1960s, particularly where there was a local manufacturer, in locations such as Ranfurly.


Windows in late 1950s and 1960s houses often had pelmets, typically in the main living and bedrooms (Figure 7). Pelmets could be a plant-on unit constructed with a machined front face and solid ends or formed by packing out the wall framing above the window and lining it with plasterboard with a cantilevered bottom edge.

Architect-designed houses

Architect-designed houses had greater variety of window types and sizes than other housing of the 1940s-60s.  Especially during the 1960s, large areas of glazing became common in architect-designed houses, along with doors providing indoor-outdoor flow.

Cost savings were sometimes achieved by omitting window sashes. Although windows were large, as they were not all required to open, so instead of installing glass into sashes studs were sometimes rebated to receive fixed glass or adjustable louvres.

Window jamb details were often varied to avoid the use of facings. Instead the cladding was butted up to the window with a back flashing inserted into the  window frame behind the junction.

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Common modifications

In some houses, existing timber windows may have been replaced with new aluminium glazing (Figure 8), particularly where direct access to outdoor living spaces such as decks have also been installed.

Whether double glazing has been installed will generally depend on when the replacement windows were installed.

Where original windows remain, some maintenance work such as replacement of hinges and stays may have been carried out. Timber windows that have not been well maintained may be in poor condition.Any original sliding aluminium doors may have required maintenance or replacement as the sliding mechanisms wear out.

Indoor/outdoor flow

Indoor/outdoor flow is likely to have been incorporated into 1940s and 1950s houses that are privately owned by the installation of more or bigger doors, and the construction of decks or terraced areas.

Depending on when modifications were carried out, doors will be timber frame, glazed French doors, aluminium ‘ranch slider’ types doors, or aluminium hinged and/or bifolding doors.