Risks associated with existing properties
The deterioration and failure of a building's structure and fabric are commonly linked to one or a combination of the following three main issues:
Dampness
Timber Decay
Cracking and Movement
All buildings, to varying extents, are subject to these significant factors. Each of the aforementioned problems encompasses various factors or sources, such as condensation (for dampness), dry rot (for timber decay), and subsidence (for movement). While the causes are limited, the specific sources are numerous, which can complicate the accurate diagnosis without a thorough investigation. Therefore, pinpointing faults in buildings can be challenging in specific scenarios due to the presence of relatively few anomalies (or symptoms) but with a wide array of potential causes and defects (Addleson,1992). Furthermore, the exact trigger mechanism of a building fault is not always immediately apparent, even if the cause (e.g., dampness) seems evident.
A combination of trigger mechanisms can lead to the occurrence of a defect. For instance, rainwater infiltration may result in dry rot, which is the most damaging type of timber decay in buildings (Ridout, 2001). While dampness is clearly the root cause in such cases, the moisture source may not be immediately apparent. In any treatment aimed at eliminating fungal attacks, the identification and removal of the moisture source is a crucial preventive measure (Palfeyman & Urquhart, 2002). Likewise, a single cause can manifest in multiple symptoms. For instance, water seepage through a block wall cavity can cause corrosion of wall ties, leading to the horizontal expansion of mortar joints and the appearance of moisture stains or soiling on the inner face of the brickwork.
Typical risks
For additional advice on common property defects, refer to the works of Son and Yuen (1996), Hinks and Cook (1997), Carillion (2001), and Douglas and Ransom (2007).
It is essential for every surveyor to assess the potential presence of the following common risks in the property under survey:
Accessibility: Lack of compliance with the Disability Discrimination Act affecting premises accessibility
Subsidence: Factors such as shrinkable clay subsoil, nearby trees, and mineworking areas
Settlement: Issues like overloading and differential settlement in lateral extensions
Heave: Expansion of clay subsoil, with increased risk in case of flooding or rising water table levels
Flooding: Proximity to rivers, streams, seas, or being situated in a flood plain area
Soil erosion: Especially in coastal areas where the coastline is subject to erosion
Pollution: Noise, disturbances from nearby properties, antisocial neighbors, and industrial processes
Deleterious materials: Including asbestos, lead, mundic, woodwool slabs, high alumina cement concrete (HACC), as described by Douglas (2006)
Fire: Risks related to flammable materials in construction or storage, accidental ignition, arson, and overheating of electrical connections
Instability: Bomb or gas blast, earthquake, storm damage, subsidence, settlement, dilapidation
Insecurity: Vulnerability to break-ins, ram-raiding
Obsolescence: See Douglas (2006)
Redundancy: See Douglas (2006)
Sick building syndrome: particularly air-conditioned buildings built or refurbished since the early 1970s
Deficiency: lacking in performance - acoustic, fire, thermal, structural
Degradation and deterioration: See Richardson (2001)
Non-traditional construction: See Chandler (1991) and Douglas (2006)
Electromagnetic radiation: Exposure to emissions from overhead electricity lines and mobile phone masts
Subsoil contamination: Seepage of radon gas or methane gas leeching into property
Illicit alterations: Removal of chimney stack or chimney breast; Removal of other supporting elements; Forming openings in load-bearing walls; Changes in the layout; Modifications to the electrical installations; Loft conversions; Window replacement.
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The information provided in these posts is for informational purposes only and should not be considered design advice, specifications, or a calculation template. We assume no responsibility or liability for the use of the information presented. For professional advice or design services, please contact us via our contact form.
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