Overview
The Bullock house is a system-built form of non-traditional housing developed during the late 1960s. Manufactured by D T Bullock & Co. Ltd, these properties reflect the construction methods and architectural priorities of the period, focusing on efficiency and cost-effective delivery.
Typical characteristics & construction
Bullock houses are typically two-storey semi-detached dwellings. Roofs are of medium pitch gable form and finished with interlocking concrete tiles. A flat-roofed entrance porch is a common identifying feature.
The primary structure uses a platform timber frame system with storey-height panels. External wall panels are sheathed in plywood, overlaid with bituminous felt, and finished with horizontal timber boarding. Internal linings consist of wallboard backed by a polyethylene vapour control layer, with polystyrene insulation between studs.
Gable walls are formed from storey-height lightweight concrete panels clad externally in brick and internally lined with plasterboard. Separating walls are lightweight concrete cavity walls lined with wallboard and insulated with glass fibre quilt.
| Element | Typical construction | Inspection focus |
|---|---|---|
| Substructure | Concrete slab with damp-proof course | Signs of settlement, moisture ingress |
| External walls | Timber frame with plywood, bituminous felt, and timber boarding | Timber decay, moisture penetration |
| Gable wall | Lightweight concrete panels with brick cladding | Cracking, panel condition |
| Floors | Concrete ground floor; plywood on timber joists to first floor | Deflection, deterioration |
| Roof | Timber trusses with bituminous felt and concrete tiles | Tile condition, felt integrity |
Potential hazards & inspection priorities
The extensive use of timber within external walls and partitions presents a risk of decay where moisture ingress occurs. Areas around openings and poorly ventilated zones require particular attention.
Original insulation materials are limited by modern standards and may contribute to reduced thermal efficiency. Bituminous felt layers can also trap moisture, increasing the risk of concealed timber deterioration.
Is this house right for you?
A Bullock house may suit purchasers who understand non-traditional construction and are prepared to assess the property based on condition rather than age alone.
- Commission a full building survey
- Review evidence of maintenance and repairs
- Consider insulation and moisture management upgrades
Mortgage & resale considerations
Lending decisions for non-traditional construction depend on property condition, construction clarity, and professional reporting. Acceptance criteria vary between lenders and may change over time.
Clear survey findings and evidence that known risks are appropriately managed are commonly influential factors.
What a survey can — and cannot — tell you
A building survey provides an informed assessment of the visible condition and construction of a Bullock house. Inspections are non-intrusive and limited to areas that are accessible at the time of inspection.
- Identify visible timber decay or moisture penetration to the timber-boarded external walls
- Assess signs of moisture ingress, particularly around openings and in poorly ventilated areas
- Comment on the concrete tile roof covering, the flat-roofed entrance porch, and the brick-clad gable walls
- Review the general condition of accessible floors, including signs of deflection or deterioration
- Highlight defects that may require repair, monitoring, or further investigation
However, there are limitations to what a survey can determine without intrusive investigation.
- Confirm the condition of timber framing concealed behind plywood sheathing, bituminous felt, and internal linings
- Determine whether moisture trapped by the bituminous felt has caused concealed timber deterioration
- Assess the condition of the lightweight concrete gable panels behind the brick cladding
- Inspect areas that are inaccessible or covered at the time of inspection
Where higher-risk indicators are identified, further specialist or intrusive investigation may be recommended.
