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On the outside, a lovely thatched roof on a delightful period cottage. . .

. . . but all is not well, as the original rafters are infested to the point of failure. . .

. . . and the thatch itself is caving in.

Persistent water penetration will lead to decay in timbers normally out of sight.

Delamination affecting clay roof tiles. This can sometimes signify the beginning of the end.

Typical delamination affecting old roofing slates, together with significant condensation forming on the undersides owing to inadequate roof void ventilation. Note the absence of an underlining.

A leaking flat roof will soon result in failure of the supporting deck.

Roof linings eventually disintegrate. This is a typical feature in many 1950s houses.

The pitch to this roof is far too shallow. Note that the tiles themselves are virtually horizontal!

An old slate roof can be susceptible to both water penetration and condensation.

Not a common problem, but rodents can cause damage to buildings in a variety of ways.

If a flat roof looks like this, it is well past its sell-by date. The supporting deck will be affected by rot and will need to be replaced.

Roof flashings have a habit of pulling out of brick joints and are a potential source of water penetration.

Most of the nails to these roof tiles have long since corroded away and the unsupported tiles will slip from time to time.

Typical decay affecting an old clay roof tile.

The lower edge of a roof lining will eventually deteriorate and allow water to run behind the guttering...

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...causing staining and eventual decay in eaves timbers and even rafters.

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Typical delamination affecting old roof slates.

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Typical deterioration in a slated roof. Repairs have been carried out by way of replacing and re-securing slipped slates with lead clips, but further slippage has occurred since such repair.

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A very poorly detailed joint where some form of alteration has been carried out to the roof frame. This joint will have little strength, relying entirely on the friction provided by the two nails.

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An unusual defect where the timbers supporting the tiles at the verge of the roof had failed.

Delamination affecting the undersides of the roof tiles.

The ends of the joists and the feet of the rafters were badly affected by rot, but all this was concealed by ceiling plaster and insulation.

Undersized/over-spanned roof trusses and the absence of cross bracing will lead to buckling in the roof members and the risk of ultimate failure.

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One cannot always assume that timbers in modern houses have been pre-treated against fungal decay and infestation.

Makeshift support to roof purlin.

A poor repair to a torn or cut roof lining.


This chimney was beyond help and in need of complete rebuilding. Not surprisingly, substantial water penetration was occurring internally.

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Excessive dampness in a chimney can bring the tarry deposits of combustion through to the external surfaces in solution, here restricted to the roof void but sometimes affecting the habitable space below.

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Chimney breasts are often removed with little thought as to how the remaining structure in the roof space above is to be supported. Here a sorry attempt has been made to transfer the load onto the ceiling joists below.

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Significant decay and erosion in the brickwork and pointing to a chimney. From the appearance of the stack it seems it could have been reduced in height.

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An accumulation of debris in the back gutter of a chimney can lead to problems with damp penetration.

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Water penetration via a chimney. The tarry products of combustion have leached through to appear on internal plastered surfaces.

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The timber framing of an old period cottage can be surprisingly resilient, but neglect can lead to rot and beetle infestation leading to rapid deterioration.

This extension had suffered subsidence, and the re-stitched brickwork where cracking previously existed is plain to see. Unfortunately, the cracking now visible is indicative of recurring movement.

Cracking through brickwork sometimes warrants further monitoring. Here, studs are fixed either side of a crack to allow accurate measurement of crack width over a period of months

This is a surprisingly common defect where a conservatory drops and pulls away from the house. This is normally serious, often requiring demolition and rebuilding.

No tricks with camera angles here; thanks to subsidence, the window really was just as it appears

The decay and erosion affecting the brickwork of this boundary wall probably resulted from the use of poor quality bricks.

Extensions can be prone to subsidence or settlement and will pull away from the original building.

Many older houses are built without a party wall above first floor ceiling level. The principals of dry-stone walling are not appropriate here.

The old steel ties connecting the two leaves of brickwork in a conventional cavity wall will be prone to corrosion and ultimate failure.

Once the outer surface of a brick has failed through erosion or spalling, the inner thickness can be remarkably soft and will be particularly vulnerable to moisture penetration.

It is easy to make assumptions. This is not a brick built house but a timber framed building with a cladding of tiles designed to imitate brickwork. Notice the thickness of the displaced tile above the bell box. This is known as mathematical tiling.

Timber framed structures have a natural tendency to twist and distort.

A badly neglected parapet wall will always result in water penetration.

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This property was built without a party wall above first floor ceiling level. There is a risk of fire spread between the two properties, as well as unauthorised entry.

Outward bowing in a side wall resulting from roof spread and inadequate lateral restraint.

The house on the left is at the end of a Victorian terrace and has begun to part company with its neighbours.


Where the surface of a floor screed breaks up at the edge of the room, and the floor is ramped up to the wall, this is usually an indicator of floor slab settlement or subsidence.

A floor problem often becomes apparent when a gap opens up beneath the skirting board. When this occurs it is almost always found that the floor is of concrete construction. This was a very unusual case where a suspended timber floor had failed.

A sloping floor can indicate structural movement or merely poor quality construction.

Here, the gap beneath the skirting board indicated substantial settlement of the concrete floor slab.

Floor slab movement can result in disruption of the floor finish.

Rot and fungal growth to a timber floor resulting from a leaking valley gutter above.

This 'temporary' support to a failed floor was in fact left in position for several years.

Wood beetle infestation in a floor can ultimately lead to complete disintegration of the boards and joists.

The end-bearing of this principal floor beam was so eaten away by decay and infestation that a new pier had to be built.

Even relatively slight floor slab movement can ruin a floor finish. Here there was differential movement as between the floors of the original building and a later extension.

Damp and Decay

The absence of a gully to this fully enclosed patio lead to a substantial dampness problem internally.

Neglected rainwater fittings can lead to substantial problems with dampness internally.

This is a timber beam supporting a substantial brick wall above. The rot was well advanced - it would be interesting to find out if the building has collapsed yet.

Wood beetle infestation is very common in older buildings.

Here a chemical damp proof course has been injected into a relatively modern wall which already has the benefit of a perfectly sound physical damp proof course. Some damp proofing contractors can be less than scrupulous.

Excessive dampness can lead to the growth of an interesting array of flora.

It is very rare that roof timbers actually fail, but it does happen! This roof purlin was affected by beetle infestation.

It is not always necessary to probe timbers for signs of decay. The crinkled surface of this skirting board is an obvious sign of rot.

Ignore this leaking roof for much longer and there may be enough for breakfast.

Rot affecting the door frame in a bathroom. The source of dampness could be rising damp, plumbing leakage, or condensation.

A moisture meter is not always needed to sense a problem.


The corrosion in the old cast iron gutter is not the main problem here. The gutter was set so far away from the lower edge of the roof tiles that water was running behind the gutter and down the front wall of the house. . .

. . . causing a major problem with water penetration internally.

The most unusual and ill-conceived cistern support we have seen to date. The structure was gradually falling apart and was dangerously unstable.

Root intrusion into drains is a common problem and will eventually lead to blockage.

Typical corrosion in an old cast iron rainwater downpipe resulting in leakage at the joint.

Electrical wiring with a sheathing of rubber or cotton braid should have been replaced a long time ago.

Leakage at the back of a WC where it joins the soil pipe is a surprsingly common problem.

An overflowing central heating header tank can be a significant hazard to the occupants below as it is sometimes very hot.

Corrosion and failure in an old galvanised steel citern.

The overflow to this central heating header tank discharges into the main cistern creating the risk of contamination of the domestic water supply.

Condensation forming on an unsuitable wooden lid to a cistern has formed a potentially toxic liquor which will drip back into the cistern and contaminate the water supply.

Lead pipework is still found in many properties.

Typical leakage at the joints between the concrete sections in Finlock guttering. This system, developed in the 1950s, didn't prove very successful but cannot easily be removed.

This WC cistern lacked an overflow pipe creating an obvious risk of flooding internally.

Old lead pipework damaged by squirrels.

Corrosion inside a steel cistern can be tolerated for a while but once it has extended through the thickness of the metal it's time for replacement.

Rust staining to the water supply is common where steel pipework is still in place, particularly common in 1950s buildings.

Close-fitting lids are highly recommended for cisterns; here protecting the water supply from bat droppings.


Bat droppings in a roof void. They tend not to cause great problems in buildings.

Structural movement affecting a brick retaining wall could mean costly repairs.

We do not carry out an Environmental Survey but do give warnings on potential health issues where appropriate. The purchaser may have spotted this one already.

The cost of rebuilding a brick boundary wall can be high.

Asbestos is present in the majority of buildings built prior to 1990. Here it is present in the ceiling boards.

Misting in the sealed unit of a double glazed window will necessitate its replacement.


Unfortunately, we don't have x-ray eyes and there are occasions when we simply cannot see certain parts of the building!

Apparently the deeds also show the boundary as a wavy line.

It is a legal requirement that all belongings must be removed from a property upon completion. Where this proves difficult or expensive, some owners can be tempted to leave them behind.

Persistent moisture has resulted in corrosion of this oil tank to such an extent that the top had the consistency of cardboard.


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