Overview of the Spacemaker House
The Spacemaker house, also known by its alternative names such as Conspan, Shepherd, and Shepherd Spacemaker, is a distinctive type of system-built property that emerged in the UK between 1959 and 1970. Designed and manufactured by the Shepherd Building Group Ltd, approximately 2,750 of these properties were constructed during this period. These homes are primarily found as bungalows and 2- and 3-storey terraced houses, featuring a medium pitch gable roof covered with concrete tiles or a flat roof covered with bituminous felt.
Historical Context and Manufacturing Details
Period and Location
The Spacemaker houses were built during a time when the UK was experiencing a housing shortage, necessitating the rapid construction of affordable homes. The period from 1959 to 1970 saw a significant push towards system-built properties, which could be assembled quickly and efficiently. These homes are typically found in suburban areas across the UK, where there was a high demand for new housing developments.
Manufacturers and Designers
The Shepherd Building Group Ltd was both the designer and manufacturer of the Spacemaker houses. This company was known for its innovative approach to construction, utilizing prefabricated reinforced concrete (PRC) panels to expedite the building process. The use of PRC panels was a hallmark of the era, aimed at reducing construction time and costs while providing durable housing solutions.
Identification Characteristics
External Features
Spacemaker houses are easily identifiable by their unique construction features. The front and rear external walls are made of eaves height PRC panels, infilled with vertical timber boarding and timber boarding below windows or to the first-floor level, with PRC panels above. The gable walls are constructed from storey height or eaves height PRC panels. Some dwellings also feature a timber-clad entrance lobby on the front elevation.
Roof and Wall Construction
The roofs of Spacemaker houses are either medium pitch gable roofs covered with concrete tiles or flat roofs covered with bituminous felt. The external walls are constructed from PRC panels, which are tied to the gable wall panels with metal brackets and infilled with timber frame panels. These panels are clad with vertical timber boarding and lined with plasterboard, with insulation between the stud frames.
Typical Characteristics and Hazards
Structural Elements
The Spacemaker house is characterized by its use of PRC panels for the main structural elements, including the external walls and gable walls. The ground floor is typically made of concrete, while the upper floors consist of timber joists on timber bearers bolted to the PRC panels. The roof structure is made of timber trussed rafters covered with concrete tiles.
Common Hazards and Risks
One of the primary concerns with Spacemaker houses is the potential for cracking and spalling of the exposed ends of the PRC panels and roof perimeter beams. The concrete used in these panels may contain blast furnace aggregate, which can lead to high rates of carbonation and low reinforcement cover. These issues can compromise the structural integrity of the property over time.
Defective Premises Act
Spacemaker houses are not typically classified as defective under the Defective Premises Act. However, due to the potential for structural issues related to the PRC panels, it is essential for prospective buyers to conduct a thorough survey to identify any existing or potential defects.
Inspecting a Spacemaker House
Pre-Inspection Preparation
Before conducting an inspection of a Spacemaker house, it is crucial to gather as much information as possible about the property. This includes reviewing any available NBA Certificates (April 1966, March 1969) and understanding the typical construction methods and materials used.
External Inspection
During the external inspection, pay close attention to the condition of the PRC panels, particularly at the exposed ends and roof perimeter beams. Look for signs of cracking, spalling, or other damage that could indicate structural issues. Additionally, inspect the roof for any signs of wear or damage to the concrete tiles or bituminous felt.
Internal Inspection
Inside the property, examine the condition of the plasterboard linings and timber frame panels. Check for any signs of moisture ingress, which could indicate issues with the external cladding or roof. Inspect the ground floor concrete for any signs of cracking or movement, and ensure that the upper floors are level and free from excessive deflection.
Typical Construction Details
Substructure
The substructure of a Spacemaker house consists of precast concrete ground beams, with a two-coat bituminous compound damp-proof course (DPC) to prevent moisture ingress.
External Walls
The external walls are constructed from eaves height room width PRC panels, located by metal dowels and tied to the gable wall panels with metal angle brackets. These panels are infilled with storey height timber frame panels, clad with vertical timber boarding, and lined with plasterboard. Insulation is placed between the stud frames to improve thermal performance.
Gable Walls
The gable walls are made of eaves height room width PRC panels and PRC apex panels, bedded on mortar and located by metal dowels. These panels are lined with polystyrene insulation and plasterboard laminate, nailed to timber fillets. Drainage holes are provided in each panel to prevent moisture buildup.
Separating Walls
Separating walls between properties are constructed from eaves height PRC panels, supported on dry-pack and bolted together with metal connecting plates. These panels are lined with polystyrene insulation and plasterboard laminate.
Partitions
Internal partitions are loadbearing storey height timber frame panels, lined with plasterboard to the first-floor level and honeycomb plasterboard to the upper floors.
Floors
The ground floor is made of concrete, while the upper floors consist of timber joists on timber bearers bolted to the front or rear PRC panels with metal bolts.
Ceilings
Ceilings are lined with plasterboard, providing a smooth finish and additional fire resistance.
Roof
The roof structure is made of timber trussed rafters, covered with concrete tiles or bituminous felt, depending on the design.
Typical Defects and Maintenance
Common Defects
The most common defects in Spacemaker houses are related to the PRC panels. These can include cracking, spalling, and carbonation of the concrete, which can compromise the structural integrity of the property. Additionally, the timber frame panels and cladding may be susceptible to moisture ingress and rot if not properly maintained.
Maintenance Tips
Regular maintenance is essential to ensure the longevity of a Spacemaker house. This includes:
- Inspecting and repairing any cracks or damage to the PRC panels.
- Ensuring that the roof covering is in good condition and free from leaks.
- Regularly checking and maintaining the timber cladding and frame panels to prevent moisture ingress and rot.
- Ensuring that the damp-proof course is intact and effective in preventing moisture ingress.
Conclusion
The Spacemaker house is a unique and historically significant type of system-built property in the UK. While these homes offer many benefits, including rapid construction and affordability, they also come with potential risks and maintenance challenges. By understanding the typical characteristics, construction methods, and common defects of Spacemaker houses, prospective buyers and investors can make informed decisions and ensure the long-term durability and safety of their investment.
At Flettons, we’re committed to safeguarding your investment. When considering a property purchase, trust our seasoned expertise to uncover any hidden risks. For a thorough building survey, get your instant quote through our online calculator or call us directly on 0330 043 4650. Your home’s safety is our top priority. Disclaimer: This article is provided for general educational purposes only and is based on industry research, professional knowledge, and experience. It does not relate to any specific property and should not be relied upon when making a purchasing decision. Prospective purchasers should always commission an independent RICS-qualified surveyor to conduct a full inspection and provide a report on the actual condition of any property of interest.
