Overview of the Loudon MK II House

The Loudon MK II house, a product of the 1970s, stands as a testament to the era’s innovative approach to residential construction. Manufactured by W Loudon & Son Ltd, these properties were designed to meet the growing demand for affordable and quickly constructed homes. With only 144 units built, the Loudon MK II houses are relatively rare, making them a unique find in today’s property market.

These two-storey semi-detached houses are typically found in suburban areas across the UK, particularly in regions that experienced significant housing development during the 1970s. The design and construction of these homes reflect the architectural trends and building technologies of the time, offering a blend of practicality and style.

Construction Details

Substructure

The foundation of the Loudon MK II house is a concrete strip foundation, which provides a stable base for the structure. This is complemented by an in-situ reinforced concrete (RC) ground beam and a concrete slab, ensuring a robust and durable substructure. A damp-proof course (DPC) is also included to prevent moisture from rising through the foundation and into the building.

External Walls

The external walls of the Loudon MK II house exhibit a variety of materials and construction techniques:

• Front and Rear Walls: These are constructed using storey-height timber frame panels up to the first-floor level. The panels are clad with horizontal timber boarding and lined with plasterboard. A vapour control layer and mineral fibre thermal insulation are placed between the studs, with breather paper and horizontal boarding providing additional protection and insulation.
• First Floor: The first-floor level features 8-inch thick pre-cast reinforced concrete (PRC) panels that incorporate windows.
• Gable Walls: The gable walls are made of storey-height 8-inch PC sandwich panels, with vertical in-situ joints containing loop reinforcement from adjacent panels. The apex of the gable is also constructed using PRC sandwich panels.

Internal Walls and Partitions

• Separating Wall: The separating wall between the semi-detached units is constructed using storey-height 7-inch PRC panels.
• Partitions: Loadbearing internal walls are made of timber stud, while non-loadbearing walls are constructed using honeycomb plasterboard.

Floors

• Ground Floor: The ground floor is a concrete slab, providing a solid and durable base.
• First Floor: The first floor consists of prefabricated floor panels supported by 7-inch by 1.5-inch timber trimmers on mild steel (MS) hangers.

Ceilings and Roof

• Ceilings: The ceilings are lined with plasterboard.
• Roof: The roof structure comprises trussed softwood rafters spaced at 24-inch centres. The roof is covered with concrete interlocking tiles laid on battens and counterbattens, providing a weather-resistant and durable covering.

Identification Characteristics

The Loudon MK II house can be identified by several distinctive features:

• Two-Storey Semi-Detached Design: These houses are typically two-storey semi-detached units, a common design for suburban homes of the 1970s.
• Medium Pitch Gable Roof: The roof has a medium pitch and is covered with concrete tiles.
• External Wall Materials: The external walls may be entirely brick, a combination of PC panels infilled with asbestos cement sheets, or horizontal timber boarding on the first floor with PRC panels above.
• Gable Wall Construction: The gable walls are constructed using storey-height PRC panels, with additional PRC panels at the apex.

Typical Hazards and Risks

Asbestos

One of the primary concerns with the Loudon MK II house is the potential presence of asbestos, particularly in the external wall panels. Asbestos was commonly used in construction materials during the 1970s due to its fire-resistant properties. However, it is now known to pose significant health risks if disturbed. It is crucial to have a professional asbestos survey conducted before any renovation or demolition work.

Reinforced Concrete Durability

The durability of the reinforced concrete used in the construction of the Loudon MK II house is another important consideration. Over time, reinforced concrete can suffer from issues such as corrosion of the steel reinforcement, carbonation, and chloride attack. These issues can compromise the structural integrity of the building if not properly addressed.

Thermal Insulation

The thermal insulation in the Loudon MK II house may not meet modern standards. While the original construction included mineral fibre thermal insulation, it may be worth upgrading to more efficient insulation materials to improve energy efficiency and reduce heating costs.

Defective Premises Act

The Loudon MK II house is not classified as defective under the Defective Premises Act. However, it is essential to conduct a thorough survey to identify any potential issues and ensure the property meets current building standards.

Inspection Guide for Surveyors

When inspecting a Loudon MK II house, surveyors should pay close attention to the following areas:

External Walls

• Check for Asbestos: Look for signs of asbestos in the external wall panels. If asbestos is suspected, recommend a professional asbestos survey.
• Inspect for Cracks and Damage: Examine the external walls for cracks, spalling, or other signs of damage that may indicate issues with the reinforced concrete.

Roof

• Inspect Roof Covering: Check the condition of the concrete tiles and ensure they are securely fixed. Look for signs of wear, damage, or missing tiles.
• Examine Roof Structure: Inspect the trussed softwood rafters for signs of rot, insect infestation, or other damage.

Internal Walls and Partitions

• Check for Structural Integrity: Ensure that loadbearing walls are structurally sound and free from significant damage.
• Inspect Non-Loadbearing Walls: Check the condition of honeycomb plasterboard partitions and look for signs of damage or deterioration.

Floors

• Inspect Ground Floor Slab: Check for signs of cracking, settlement, or other issues with the concrete slab.
• Examine First Floor Panels: Ensure that the prefabricated floor panels are securely fixed and free from significant damage.

Ceilings

• Check for Sagging or Damage: Inspect the plasterboard ceilings for signs of sagging, cracking, or other damage.

Thermal Insulation

• Assess Insulation Quality: Check the condition of the mineral fibre thermal insulation and consider recommending an upgrade to more efficient insulation materials.

Typical Defects Common in the Loudon MK II House

Asbestos-Related Issues

As previously mentioned, the presence of asbestos in the external wall panels is a significant concern. Asbestos-containing materials can become hazardous if disturbed, releasing fibres into the air that can be inhaled and cause serious health issues. It is essential to handle asbestos with care and follow proper safety protocols.

Concrete Deterioration

Reinforced concrete can suffer from various forms of deterioration over time, including:

• Corrosion of Steel Reinforcement: Exposure to moisture and chlorides can cause the steel reinforcement within the concrete to corrode, leading to cracking and spalling of the concrete.
• Carbonation: Carbonation is a chemical reaction that occurs when carbon dioxide from the air penetrates the concrete and reacts with the calcium hydroxide in the cement. This process can reduce the alkalinity of the concrete, making the steel reinforcement more susceptible to corrosion.
• Chloride Attack: Chlorides from de-icing salts or marine environments can penetrate the concrete and cause corrosion of the steel reinforcement.

Thermal Insulation Deficiencies

The original mineral fibre thermal insulation used in the Loudon MK II house may not provide adequate thermal performance by modern standards. Upgrading the insulation can improve energy efficiency and reduce heating costs.

Timber Frame Issues

The timber frame panels used in the construction of the external walls and internal partitions can be susceptible to issues such as:

• Rot: Timber can rot if exposed to moisture over an extended period. It is essential to check for signs of rot and address any sources of moisture.
• Insect Infestation: Timber can also be vulnerable to insect infestations, such as woodworm. Inspect the timber for signs of infestation and treat as necessary.

Variants of the Loudon MK II House

There are several variants of the Loudon MK II house, each with different external wall materials:

• Brick Throughout: Some Loudon MK II houses have external walls constructed entirely of brick, providing a more traditional appearance and potentially reducing the risk of asbestos-related issues.
• PC Panels with Asbestos Cement Sheets: In this variant, the external walls are made of PC panels infilled with storey-height timber frame panels clad with asbestos cement sheets. This variant poses a higher risk of asbestos-related issues.
• Horizontal Timber Boarding and PRC Panels: Another variant features horizontal timber boarding on the first floor level with PRC panels above. This variant combines the aesthetic appeal of timber with the durability of PRC panels.

References and Further Reading

For more detailed information on the inspection and assessment of reinforced concrete durability, surveyors can refer to the following publications:

• Corrosion of Steel in Concrete (BRE Digest 444, Parts 1–3)
• Repair and Maintenance of Reinforced Concrete (BR 254)
• Carbonation Depths in Structural-Quality Concrete (BR 19)

These resources provide valuable guidance on identifying and addressing issues related to reinforced concrete, ensuring the long-term durability and safety of the Loudon MK II house.

Conclusion

The Loudon MK II house, with its distinctive design and construction, offers a unique opportunity for home buyers and investors. However, it is essential to be aware of the potential hazards and risks associated with this property type, particularly the presence of asbestos and the durability of the reinforced concrete. By conducting a thorough survey and addressing any identified issues, you can ensure that the Loudon MK II house remains a safe and comfortable home for years to come.

At Flettons, we’re committed to safeguarding your investment. When considering a property purchase, trust our seasoned expertise to reveal any hidden threats. For a thorough building survey, get your instant quote through our quote calculator or reach out directly at 0203 691 0451. Your home’s safety is our top priority.

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