Introduction to the Boot Beaucrete House

The Boot Beaucrete house, a unique and rare property type, stands as a testament to the innovative construction methods of the early 20th century. Manufactured by Henry Boot & Sons Ltd in 1939, only two of these properties were ever built, making them a rare find in the UK property market. This article delves into the intricate details of the Boot Beaucrete house, providing home buyers and investors with essential information to make informed decisions.

Historical Context and Manufacturing Details

Manufacturers and Designers

Henry Boot & Sons Ltd, a prominent construction company in the early 20th century, was both the manufacturer and designer of the Boot Beaucrete house. Known for their innovative approach to construction, Henry Boot & Sons Ltd played a significant role in the development of system-built properties during this period.

Period Built and Typical Locations

The Boot Beaucrete houses were constructed in 1939, a time when the UK was on the brink of World War II. These properties are typically found in areas where there was a need for rapid housing development, often in suburban locations. However, given that only two were built, their exact locations are not widely documented.

Alternative Names

The Boot Beaucrete house is also known simply as the “Boot” house, a nod to its manufacturer, Henry Boot & Sons Ltd.

Identification Characteristics

Exterior Features

The Boot Beaucrete house is a two-storey semi-detached property with several distinctive features:

• Steep Pitch Hipped Roof: Covered with plain concrete tiles, the roof has a steep pitch and a hipped design.
• External Walls: Constructed entirely of Precast Reinforced Concrete (PRC) panels.
• Bay Windows: A flat-roofed single-storey bay window is present on the front elevation.
• Rear Extension: A single-storey flat-roofed extension is located at the rear.
• Front Door Surrounds: Made of Precast Concrete (PC), these surrounds add to the unique aesthetic of the property.
• Chimney Stack: Centrally placed, the chimney stack is a prominent feature of the house.

Interior Features

• Ground Floor: Concrete slab construction.
• First Floor: Granwood on Precast Concrete (PC) slabs with brick aggregate on PC beams.
• Partitions: Made of foamed slag aggregate PC room-length panels, cored at intervals with reinforcement inserted and grouted in position.

Construction Details

Substructure

The substructure of the Boot Beaucrete house consists of concrete strip footings with PRC panel cavity underbuilding infilled with concrete. A Damp Proof Course (DPC) is also present to prevent moisture ingress.

Frame

The frame is constructed using double 3 1/2″ x 7″ PRC columns bolted together through nibs. External columns reach eaves height, while internal columns are storey height. Continuous Reinforced Concrete (RC) ring beams provide additional structural support.

External Walls

The external walls are made of dense aggregate PRC panels with recessed horizontal joints and flanges. A cavity is present, filled with 3″ foamed slag aggregate PC panels. Galvanised metal wall ties with bent pin fixing and timber wedges are used to secure the panels.

Separating Wall

The separating wall between the semi-detached properties is constructed using brick, cavity, and 3″ foamed slag aggregate PC panels.

Roof

The roof is supported by timber trusses, covered with bituminous felt and plain concrete tiles.

Typical Hazards and Risks

Reinforced Concrete Durability

One of the primary concerns with the Boot Beaucrete house is the durability of the reinforced concrete used in its construction. Over time, reinforced concrete can suffer from corrosion, leading to structural issues. Key references for understanding and assessing these risks include:

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

Designated Defective

The Boot Beaucrete house is designated as defective under the Defective Premises Act. This designation means that the property may have inherent structural issues that could affect its safety and habitability.

Inspection and Assessment Guide

Pre-Inspection Preparation

Before inspecting a Boot Beaucrete house, it is essential to gather all relevant documentation, including previous survey reports, maintenance records, and any available construction plans. Familiarising yourself with the typical characteristics and potential defects of this property type is crucial.

External Inspection

• Roof: Check for any signs of damage or wear on the concrete tiles and bituminous felt. Inspect the timber trusses for signs of rot or insect infestation.
• Walls: Look for cracks, spalling, or other signs of deterioration in the PRC panels. Pay particular attention to the joints and flanges.
• Bay Windows and Extensions: Inspect the flat roofs for water pooling or damage. Check the PC front door surrounds for cracks or other signs of wear.
• Chimney Stack: Ensure the chimney stack is structurally sound and free from cracks or leaning.

Internal Inspection

• Ground Floor: Check the concrete slab for cracks or signs of settlement. Ensure the DPC is intact and effective.
• First Floor: Inspect the Granwood and PC slabs for any signs of damage or wear. Check the PC beams for structural integrity.
• Partitions: Look for cracks or other signs of deterioration in the foamed slag aggregate PC panels. Ensure the reinforcement is intact and properly grouted.
• Ceilings: Although the ceiling construction is not well-documented, check for any signs of sagging, cracks, or water damage.

Structural Assessment

Given the potential for reinforced concrete corrosion, a thorough structural assessment is essential. This may involve:

• Carbonation Testing: To determine the depth of carbonation in the concrete, which can affect the durability of the reinforcement.
• Corrosion Testing: To assess the extent of any corrosion in the steel reinforcement.
• Load Testing: To ensure the structural elements can safely support the intended loads.

Typical Defects and Maintenance

Common Defects

• Concrete Deterioration: Over time, the PRC panels and other concrete elements may suffer from spalling, cracking, or other forms of deterioration.
• Corrosion of Reinforcement: The steel reinforcement within the concrete can corrode, leading to structural issues.
• Water Ingress: Flat roofs and other areas may be prone to water ingress, leading to damp and other related issues.
• Thermal Bridging: The construction methods used in the Boot Beaucrete house may result in thermal bridging, leading to heat loss and potential condensation issues.

Maintenance Tips

• Regular Inspections: Conduct regular inspections to identify and address any issues early.
• Concrete Repairs: Address any signs of concrete deterioration promptly to prevent further damage.
• Waterproofing: Ensure flat roofs and other areas are properly waterproofed to prevent water ingress.
• Thermal Insulation: Consider adding thermal insulation to reduce heat loss and prevent condensation issues.

Conclusion

The Boot Beaucrete house, with its unique construction and historical significance, presents both opportunities and challenges for home buyers and investors. Understanding the typical characteristics, potential hazards, and maintenance requirements of this property type is essential for making informed decisions.

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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