Overview of the Morrell House
The Morrell House, also known as the Bradley House, is a unique and rare property type in the UK. Designed by K Morrell and manufactured by E H Bradley & Sons, these properties were constructed in the 1940s. Only two of these two-storey semi-detached houses were ever built, making them a rare find for home buyers and investors alike. This article will delve into the intricate details of the Morrell House, including its construction, typical characteristics, potential hazards, and inspection tips.
Historical Context and Manufacturing
Period Built and Location
The Morrell House was constructed in the 1940s, a period marked by post-war reconstruction efforts. These houses are typically found in areas that were part of the rapid housing development schemes initiated to address the housing shortage following World War II. Given their limited number, they are often located in specific regions where E H Bradley & Sons had their operations.
Manufacturers and Designers
E H Bradley & Sons were the manufacturers behind the Morrell House, with the design credited to K Morrell. The collaboration aimed to create durable and cost-effective housing solutions during a time when traditional building materials were scarce. The use of Precast Reinforced Concrete (PRC) was a significant innovation, allowing for quicker construction times and reduced costs.
Typical Characteristics of the Morrell House
External Features
The Morrell House is easily identifiable by its steep pitch gable roof covered with concrete tiles. The external walls are rendered throughout, providing a uniform and robust appearance. Metal windows are fixed into PRC surrounds, and the houses feature combined PRC eaves course and gutter units. Circular concrete chimney pots are another distinctive feature.
Internal Features
Internally, the Morrell House boasts a concrete ground floor and a first floor made of 4″ x 1′ 3″ x 8′ PRC dished units. The ceilings are finished with lime mortar and distemper, adding to the period charm of the property. The separating wall is an 8″ dense PC block cavity wall tied to the frame at the first-floor level, ensuring structural integrity.
Construction Details
Substructure
The substructure of the Morrell House includes a concrete pad below column bases, a concrete strip foundation, and a concrete slab. A Damp Proof Course (DPC) is also integrated to prevent moisture ingress.
Frame
The frame consists of storey-height 6″ x 4″ PRC columns with projecting arms at the head and foot. Wall columns have projections on both sides, while corner columns have projections on one side. PRC lintels at the first-floor level are seated on and bolted to column arms, supported by RSA cleats at corner columns. An RSJ is fixed to wall columns with RSC cleats, supported at mid-span by a 6″ x 4″ PRC column.
External Walls
The external walls are rendered and constructed using 13 1/2″ x 5 5/8″ x 2 1/2″ dished dense PC blocks and 10 1/2″ x 5 5/8″ x 4 1/2″ plain-faced quoin blocks at returns. The walls feature a cavity filled with 2″ foamed slag PC blocks with joggled vertical joints, timber battens lined with fibreboard, and longitudinal ties grouted into PRC columns. Square Grip wall ties and continuous lead flashing across the cavity at the first-floor level and gable wall at the first-floor ceiling level are also present.
Roof
The roof is constructed with timber rafters and covered with concrete tiles, providing durability and weather resistance.
Typical Hazards and Risks
Structural Issues
One of the primary concerns with Morrell Houses is the potential for structural issues due to the use of PRC. Over time, PRC can deteriorate, leading to structural weaknesses. Diagonal cracking of render below first-floor windows is a common issue, indicating potential problems with the underlying PRC structure.
Corrosion of Steel Reinforcement
The corrosion of steel reinforcement within the PRC is another significant risk. This can lead to spalling of the concrete and further structural degradation. Regular inspections and maintenance are crucial to mitigate this risk.
Moisture Ingress
Despite the presence of a DPC, moisture ingress can still be a concern, particularly if the DPC has been compromised. This can lead to damp issues within the property, affecting both the structural integrity and the living conditions.
Defective Premises Act
The Morrell House is not classed as defective under the Defective Premises Act. However, given the potential issues with PRC and the age of the properties, it is essential to conduct thorough inspections and assessments to ensure the property is safe and habitable.
Inspection Tips for Surveyors
Diagonal Cracking
When inspecting a Morrell House, pay close attention to any diagonal cracking of the render below first-floor windows. This can be an early indicator of structural issues with the PRC.
Corrosion of Steel in Concrete
Refer to the BRE Digest 444 (Parts 1-3) for guidance on inspecting and assessing the durability of reinforced concrete. Look for signs of corrosion, such as rust stains or spalling concrete.
Carbonation Depths
Assess the carbonation depths in structural-quality concrete using the guidelines provided in BRE Digest 19. Carbonation can lead to the corrosion of steel reinforcement, so it is crucial to determine the extent of carbonation within the PRC.
Moisture Levels
Check for signs of moisture ingress, particularly around the DPC and any areas where the render may be compromised. Use a moisture meter to assess the moisture levels within the walls and floors.
Typical Defects in Morrell Houses
Render Cracking
As mentioned earlier, diagonal cracking of the render below first-floor windows is a common defect. This can indicate underlying issues with the PRC structure and should be investigated thoroughly.
Spalling Concrete
Spalling concrete is another typical defect, often caused by the corrosion of steel reinforcement within the PRC. Look for areas where the concrete surface has flaked or broken away, exposing the steel reinforcement.
Damp Issues
Damp issues can arise from compromised DPC or moisture ingress through the render. Look for signs of damp, such as mould growth, peeling paint, or a musty smell.
Roof Issues
Given the age of the properties, the roof may also present issues such as missing or broken tiles, damaged timber rafters, or inadequate insulation. Inspect the roof thoroughly to identify any potential problems.
Maintenance and Repair
Addressing Structural Issues
If structural issues are identified, it is essential to address them promptly to prevent further deterioration. This may involve repairing or replacing damaged PRC elements, reinforcing steel, or applying protective coatings to prevent corrosion.
Render Repairs
Cracked or damaged render should be repaired to prevent moisture ingress and further structural issues. Use appropriate materials and techniques to ensure a durable and effective repair.
Damp Proofing
If damp issues are identified, consider installing or repairing the DPC to prevent moisture ingress. Additional measures such as improved ventilation or the use of dehumidifiers may also be necessary to address damp problems.
Roof Maintenance
Regular roof maintenance is crucial to ensure the longevity of the property. Replace any missing or damaged tiles, repair or replace damaged timber rafters, and ensure adequate insulation is in place.
Conclusion
The Morrell House, with its unique design and historical significance, presents both opportunities and challenges for home buyers and investors. Understanding the typical characteristics, potential hazards, and inspection tips can help ensure a successful purchase and long-term maintenance of these rare properties.
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.
