Historical Context and Manufacturing Background

The Hillcon house, also known as the Hills house, is a distinctive type of system-built property that emerged in the early 1950s. Manufactured by Hills (West Bromwich) Ltd and designed by Hills Patent Glazing Co. Ltd, these properties were constructed in 1952. Only 100 units were built, making them relatively rare in the UK housing market. These two-storey semi-detached houses are primarily found in specific regions, often in suburban areas where post-war housing demands were high.

Identification Characteristics

Identifying a Hillcon house involves recognizing several unique architectural features. These properties typically have a medium pitch gable roof covered with interlocking concrete tiles. The external walls are harled (roughcast) throughout, with smooth render around door and window openings. The door and window surrounds are made of pre-stressed (PS) concrete, and a flat pre-cast (PC) canopy is positioned over the front door. These characteristics make Hillcon houses easily distinguishable from other post-war properties.

Construction Details

Substructure

The substructure of a Hillcon house consists of concrete strip footings with brick under-building stepped internally. A damp-proof course (DPC) is also present to prevent moisture ingress from the ground.

Frame

The main frame is composed of 26 steel lattice stanchions, with two being single-storey and six double rolled steel angle (RSA) mock perimeter beams. Additionally, there is one steel lattice floor support beam, two RSA perimeter ties, steel lattice floor joists, eight steel lattice trusses, and one RSA mock truss. The frame is protected by galvanization or a combination of red oxide and black bituminous paint to prevent corrosion.

External Walls

The external walls are constructed using a combination of brick, cavity, and timber framing lined with plasterboard. An insulation blanket is placed within the cavity to enhance thermal efficiency. The separating wall between semi-detached units is a 9-inch brick wall laid on edge.

Partitions

Internal partitions are made of timber stud lined with plasterboard, providing a lightweight yet sturdy structure for interior walls.

Floors

The ground floor is constructed of concrete on expanded metal lathing, supported by steel lattice joists. The first floor features tongue-and-groove (T&G) boarding on battens, also supported by steel lattice joists.

Ceilings

Ceilings throughout the property are made of plasterboard, offering a smooth and uniform finish.

Roof

The roof structure includes timber battens, timber sarking, and interlocking concrete tiles, providing a robust and weather-resistant covering.

Typical Hazards and Risks

Corrosion Issues

One of the most significant risks associated with Hillcon houses is the severe corrosion of steel lattice stanchions, particularly at their bases. This corrosion can compromise the structural integrity of the property. Additionally, superficial corrosion of galvanized steelwork is common, which, while less severe, still requires attention to prevent further deterioration.

Moisture Ingress

Due to the age of these properties, moisture ingress can be a concern, particularly if the damp-proof course (DPC) has failed or if there are issues with the external render. Moisture can lead to internal dampness, mould growth, and potential damage to timber elements.

Insulation and Energy Efficiency

While the insulation blanket within the cavity walls provides some thermal efficiency, these properties may not meet modern energy efficiency standards. Upgrading insulation and installing energy-efficient windows and doors can help improve the property’s overall energy performance.

Defective Premises Act Considerations

The Hillcon house is not classed as defective under the Defective Premises Act. However, due to the potential for severe corrosion and other age-related issues, it is crucial for prospective buyers to commission a thorough building survey before purchase. This survey should identify any existing defects and provide recommendations for necessary repairs or maintenance.

Inspection Guide for Surveyors

When inspecting a Hillcon house, surveyors should pay close attention to the following areas:

Steel Lattice Stanchions

Inspect the bases of steel lattice stanchions for signs of severe corrosion. Use a moisture meter to check for dampness around the bases, as this can accelerate corrosion.

Galvanized Steelwork

Check for superficial corrosion on galvanized steelwork. While this may not be immediately dangerous, it can indicate areas where protective coatings have failed and need reapplication.

External Render

Examine the external harled render for cracks or damage. Any breaches in the render can allow moisture ingress, leading to internal dampness and potential structural issues.

Damp-Proof Course (DPC)

Verify the condition of the DPC. Look for signs of rising damp, such as damp patches on internal walls, peeling paint, or a musty smell.

Insulation

Assess the condition of the insulation blanket within the cavity walls. Upgrading insulation can significantly improve the property’s energy efficiency and reduce heating costs.

Roof Structure

Inspect the roof structure, including timber battens and sarking, for signs of rot or damage. Ensure that the interlocking concrete tiles are secure and in good condition.

Internal Partitions

Check the condition of internal timber stud partitions. Look for signs of movement or damage, which could indicate underlying structural issues.

Typical Defects in Hillcon Houses

Structural Corrosion

As previously mentioned, severe corrosion of steel lattice stanchions is a common defect in Hillcon houses. This corrosion can weaken the structural integrity of the property and requires immediate attention.

Moisture-Related Issues

Moisture ingress, rising damp, and condensation are common issues in older properties like Hillcon houses. These problems can lead to internal dampness, mould growth, and damage to timber elements.

Insulation Deficiencies

The original insulation in Hillcon houses may not meet modern standards. Upgrading insulation can improve energy efficiency and reduce heating costs.

Roof Damage

The roof structure, including timber battens and sarking, can suffer from rot or damage over time. Regular maintenance and timely repairs are essential to prevent water ingress and further deterioration.

External Render Cracks

Cracks in the external harled render can allow moisture ingress, leading to internal dampness and potential structural issues. Regular inspections and prompt repairs are necessary to maintain the integrity of the external walls.

Maintenance and Repair Recommendations

Addressing Corrosion

To address severe corrosion of steel lattice stanchions, it is essential to remove any rust and apply a protective coating. In some cases, replacing severely corroded stanchions may be necessary to ensure the property’s structural integrity.

Improving Insulation

Upgrading the insulation within the cavity walls and installing energy-efficient windows and doors can significantly improve the property’s energy performance. This can lead to lower heating costs and a more comfortable living environment.

Roof Maintenance

Regular roof inspections and maintenance are crucial to prevent water ingress and damage to the roof structure. Replace any damaged or missing interlocking concrete tiles and repair any rot or damage to timber battens and sarking.

External Render Repairs

Repair any cracks or damage to the external harled render promptly to prevent moisture ingress. Regular inspections and maintenance can help maintain the integrity of the external walls.

Damp-Proof Course (DPC) Upgrades

If the existing DPC has failed, consider installing a new DPC to prevent rising damp. This can help protect internal walls from dampness and potential damage.

Conclusion

The Hillcon house, with its unique architectural features and historical significance, offers a distinctive option for home buyers and investors in the UK. However, due to the potential for severe corrosion and other age-related issues, it is crucial to commission a thorough building survey before purchase. By addressing common defects and implementing necessary repairs and maintenance, Hillcon houses can provide a comfortable and energy-efficient living environment.

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.

---