15 Potentially Serious Defects

Flat Roofs

If the property has been extended it may well have a flat roof. The lifespan of a flat roof covering is much shorter than that of tiles or slates. You can often get a good view of the flat roof from the first floor windows. If it looks bare or is bulging up in areas it is likely to be at the end of it lifespan.

External Ground Level.

One of the most common causes of dampness is a high external ground level. The external ground level should be at least 150mm (6″) below the damp proof course. Drives and patios are often re-laid by amateurs who breach this important guideline. If the damp proof level cannot be easily seen look around the top of any rendered plinth or about 275mm (13″) below the internal floor level.

Injected Damp Proof Course

If previous damp problems have occurred it is possible that a damp roof course has been injected. This involves drilling a series of holes adjacent to where the original DPC would have been and injecting them with a fluid which will increase the density of the brickwork and prevent dampness passing through. The effectiveness of such systems is questionable and the associated workmanship often leaves much to be desired. Such treatment is normally covered by a warranty. You should check that the company that issued the warranty is still trading.

Chimneys Stacks

Chimney stacks are susceptible to movement and deterioration of pointing. Due to difficulty of access remedial work to a chimney breast can be expensive. Stand at the front or rear of the property in line with the chimney breast. Does it look plumb? A very slight lean can be tolerated but anything more significant and you are looking at rebuilding it.


Trees close to buildings can affect the foundations and drains. Each influencing distance . This is the area around the tree upon which the trees roots affects the equilibrium of the ground.


The easiest place to spot structural movement is around door and window frames. Stand back and see how they line up with the other lines above. Some movement is to be expected in older style properties and is usually only treated as a serious defect if it is recent or progressive. If there has been significant structural movement to a property you will need a fairly detailed surveyors report.

Lateral Restraints

If a property has suffered from lateral movement in the past it may well have had restraint bars fitted. These run through the property from side to side and will have visible plates showing on the side of the property. It is more common to see these fitted on older style properties. Occasionally restraint bars were fitted in the years following the construction of some Victorian properties when the first signs of lateral movement were noticed.

Chimney Breasts

When chimney breasts are no longer in use they are often blocked off. Where this is the case the chimney breast should be vented to allieviate the build up of moisture within. This moisture can penetrate through to the internal surface of the chimney breast and cause staining.

Soil & Vent Pipes

On older buildings the Soil & Vent pipe (the 4” diameter pipe in to which the property’s waste pipes connect) is often run in cast iron. The rear of these pipes is difficult to reach with a paint brush and is often left exposed to the elements resulting in corrosion.

Sub-floor Ventilation

Where the ground floor of a house is suspended timber joisted and boarded the void below that floor requires ventilation to prevent decay. This is achieved by vents placed in the external walls just above the external ground level. It is essential that these are kept clear. Often a porch or a rear extension with a solid concrete floor is added to the property obstructing these vents.


Older style sash windows require regular maintenance. You should check that both top and bottom sashes are free flowing and that the sash cords are intact. Modern uPVC casements are vulnerable to thermal movement and are often poorly fitted. Check that casement open and close freely. Also check for trapped condensation. The seal to the double glazed unit can fail allowing condensation to become trapped between the two pieces of glass. There is no remedy for this other than replacing the sealed unit.

Timber Decay Caused by Insect Attack

The first sign of beetle attack is identifying exit holes on the surface of the timber. Wood boring beetles thrive in warm damp areas so it is advisable to look closely in areas where the timber is usually exposed such as in understairs cupboards or on stairs down to basements

Electrical Installation

Locate the consumer unit and determine its age. Modern units will have circuit breakers rather than old style fuses or fuse wire. See is any additional circuits have been added on a separate unit. A modern consumer unit does not necessarily mean that the property has been re-wired. Look at the number of sockets; are there a sufficient number for modern use and where are they positioned? It is not permitted to put sockets in the skirting board in a modern installation.

Removed Chimney Breasts.

If any of the chimney breasts have been removed you should follow the line of the chimney up to check that chimneys above have also been removed or are properly supported. The most common form of support is 2-3 steel supports known as gallows brackets with a lintel laid across supporting the remaining brickwork.

Loft Conversions

You should be looking for signs of whether the loft was converted for use as a bedroom or just for storage. If it is to be used for sleeping accommodation it should be closed off with a partition and there should be an escape route out to the front door.  Bounce up and down on the floor a couple of time to test if a new floor was installed or if the first floor ceiling joists have been used. Your solicitor should always request a Building Regulations completion certificate for loft conversions but these checks may save you the time and money involved in going that far.

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