Overview
The Tarran Temporary Bungalow, often referred to as a “Prefab” or “Tarran Mark IV,” is a form of non-traditional housing developed in the immediate post-war period. These properties were manufactured by Tarran Industries Ltd between 1944 and 1956 to address acute housing shortages, providing rapid accommodation for displaced families and returning servicemen.
Approximately 8,000 units were constructed, including variants such as the Dorran, Myton, and Newland. They are most commonly found in urban and suburban locations where demand for fast, economical housing was highest.
Typical characteristics & construction
These properties are detached, single-storey bungalows with a shallow pitch gable roof, typically finished with profiled asbestos cement sheets. This was a cost-effective and durable solution at the time, although the presence of asbestos is now a significant consideration.
External walls are formed from storey-height aggregate-faced precast reinforced concrete (PRC) panels. These are fixed through timber posts and backed with bituminous felt, insulation, and plasterboard. A metal cowl to the chimney terminal is a common identifying feature.
Internally, construction is lightweight, with timber stud partitions lined in plasterboard. Floors are formed using tongue-and-groove boarding on timber joists, while ceilings are also plasterboard. The roof structure comprises timber frame units fixed to both central partitions and external walling, with insulation provided at ceiling level.
The substructure is typically a concrete raft foundation, providing a continuous base across the footprint of the building.
| Element | Typical construction | Inspection focus |
|---|---|---|
| Substructure | Concrete raft foundation | Cracking, movement, overall stability |
| External walls | Precast reinforced concrete panels with timber posts | Cracking, spalling, carbonation, joint condition |
| Roof | Shallow pitch with asbestos cement sheets on timber structure | Sheet condition, fixings, timber integrity |
| Internal walls | Timber stud with plasterboard lining | Dampness, distortion, timber condition |
| Floors | T&G boarding on timber joists | Deflection, rot, ventilation |
Potential hazards & inspection priorities
The presence of asbestos within the roof covering is a primary consideration. While asbestos cement sheets are often stable if undisturbed, deterioration or damage alters the risk profile and typically necessitates specialist management or removal.
Carbonation of the precast reinforced concrete panels is a known issue with this construction type. In practice, this was evident during inspection of similar properties, with higher carbonation levels often recorded internally. As carbonation progresses, embedded steel reinforcement becomes vulnerable to corrosion, which can lead to cracking and localised failure.
Cracking and spalling to concrete panels are commonly associated with this process. Once reinforcement begins to corrode, expansion leads to surface breakdown, which was evident during inspection in comparable dwellings and should be treated as a priority defect where present.
Timber elements, particularly posts, wall plates, and joists, are susceptible to rot where moisture ingress has occurred. This is a common issue in properties of this type, especially where maintenance has been inconsistent or ventilation is limited.
Is this house right for you?
These properties require a clear understanding of non-traditional construction and its implications. The original design life was limited, and ongoing performance is heavily dependent on maintenance and any subsequent alterations.
- Careful assessment of PRC panel condition is essential
- Allow for potential asbestos management or removal
- Consider the condition of original timber structural elements
Where defects such as cracking, spalling, or timber decay are already present, further investigation is usually justified before proceeding.
Mortgage & resale considerations
Tarran Temporary Bungalows are designated as defective under the Housing Defects Act 1984, which directly affects lender and insurer appetite. In practice, this can restrict mortgage availability and influence resale prospects.
Lenders typically require clear evidence of condition and, in some cases, confirmation of approved repair schemes where applicable. The presence of unresolved structural defects or unmanaged asbestos will usually impact lending decisions.
What a survey can — and cannot — tell you
A building survey provides an informed assessment of the visible condition and construction of a Tarran Temporary Bungalow. Inspections are non-intrusive and limited to areas that are accessible at the time of inspection.
- Identify visible cracking to PRC wall panels and associated finishes
- Assess signs of dampness, moisture ingress, and condensation risk
- Comment on roof coverings, drainage details, and external envelope condition
- Review the general condition of accessible floors, ceilings, and structural elements
- 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 concealed reinforcement within the PRC panels
- Assess hidden structural elements behind finishes or linings
- Determine the full extent of carbonation or internal concrete deterioration
- 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.
