We never did get to the bottom of this one.  The floor had obviously been flooded quite badly but there were no obvious source for the water, as you can see from the report below.  Behind the rear wall of the flat was an extensive void, and at first I though that this had maybe flooded due to a drainage problem in the adjacent road.  Eventually though, this became less likely. 

A flood from the flat above was also ruled out and condensation was definitely not the cause.  The NHBC, insurance assessors, Uncle Tom Cobbly and all eventually became involved, and of course no one would admit any liability. The client eventually took it on the chin, paid for the repairs and sold the property. 

I learned later that there had been considerable confusion as to the exact time the fault had been reported by the letting agent; and it turned out that the flat may have been empty for some considerable time after the last tenant left before the letting agent visited the house to do an inventory. 

Little Weed (you'll have to be old enough to remember Bill and Ben) told me that the  last tenant had flooded the house, not said anything, and just left.  I think Little Weed may have been right!

Client(s)                                   Mr & Mrs T

Property                                   Huddersfield

Instructions                             

To inspect the property and report on an incidence of dampness in the flooring throughout the property.

Background                            

The clients purchased the property approximately two and a half years ago for the purposes of letting.  The last tenant reported that there was dampness to the floors in the bedroom, bathroom and living room.  Prior to this there had been an issue with water entering this property from a flat above and the client had approached the NHBC (the property is still within its ten year warranty period) in an effort to achieve a resolution of the problem.  The NHBC had opined at that time that this was a condensation issue related to the earlier leak.

Disclosures                             

I am not aware of any affiliation, financial or otherwise, with the client or the property.

Limitations                              

 Limited to the instructions.

Restrictions                             

Nil

Date of Survey                       

Various dates between 9^th and 14^th October 2005

Weather                                   

Fine with the exception of the last visit, which was immediately after heavy rain.

Viewing Orientation                

All observations are made looking towards the house from the front. 

Type of Property                       

Purpose built, ground floor 'under-dwelling' flat.  Nine years old.

External Observations

The property is one of a block of flats built into the side of a banking that supports ****Road . Its front is its only external elevation and this faces in a northerly direction towards Manchester Road.  Immediately above this property are numbers a and b  ***Road.  These properties are accessed from the road itself whist the subject property is accessed via steps to the side of the block.

Immediately to the front of the subject property is a flagged access way, whose level is below that of the internal level of the floor.                                                

In order to ascertain if water had been entering from either of the flats above, access was gained and they were thoroughly inspected.  This included removal of bath panels etc. 

No leaks, or signs of old leaks, were found in either of these two properties.                                               

Externally, there are no other issues,.                                                 

Internal Observations

Upon entering the flat a strong musty smell was observed.  The carpets in both the living room and the bedroom had been pulled back approximately one metre from the rear wall and the ‘Caberfloor’ flooring grade chipboard was exposed.  In most visible areas, this was black in colour, soft to the touch and quite sodden.

In the living room, upon pulling the carpets back further toward the front of the room, the wet areas extended for approximately three quarters of the width from front to back and for approximately half the width left to right.  The point of origin of this dampness was towards the rear left hand corner of the room and extends beneath an internal door into a small storage room.                                               

Whilst pulling back the carpet in this room, my foot went through the Caber flooring and into the foam polystyrene insulation board beneath.                                               

There were no visible signs of dampness on the rear wall, which is plasterboard; dab fixed onto the block behind, and there were no signs of mould.                                               

The skirting boards were inspected but these did not seem to have suffered any damage, at least to their show side.  However, the carpet gripper that was fixed to the floor had suffered considerably from the brown rot Coniophoria puteana, and I estimate this had been rotting for at least twelve months, and perhaps for even longer than that.                                               

On a later visit, the Caber flooring was removed, almost in its entirety, and the skirting boards along the rear wall were also removed.                                               

The rear of the skirting board was suffering from a white rot, Phellinus contiguus and there were distinct signs of rot on the underside of the Caber flooring, even though it pre-treated against fungal attack during manufacture.  Nevertheless, a rot of some kind was clearly active.                                               

Furthermore, the polystyrene boards towards the rear of the room were several times heavier than their normal dry weight and had obviously absorbed a fair amount of water.                                               

In the bedroom, the staining is not as large as that in the living room and seems to be orientated towards the right hand side of the room, extending beneath the internal stud wall that forms the left hand side of the bathroom.  The flooring in here has not yet been lifted and examination of the skirting board has been superficial.                                               

In the bathroom, the bath side and end panels were removed but the flooring in this region is not as damaged as elsewhere.  The bathroom seems to be at the periphery of the source rather than its centre, thus ruling out a plumbing leak in this area.  I also removed the pipe boxing from around the air inlet valve on the soil system; this too does not appear to have been leaking.

Finally, I drilled a core sample from the rear of the floor in the living room and ran a Protimeter salt test on the contents.  This proved to be strongly positive for Chloride salts whilst giving a negative reading for Nitrates.  This, by itself, is inconsistent with the presence of ground water but may indicate contamination by a mains water leak.  Salts are often absent from tanking failures due to the speed with which the water progresses from the external surface, e.g. pavement, to the wall/floor junction or under-screed area.  This rapid transit does not allow it to collect salts, as it would were it resident in the ground for longer periods.

Conclusion                             

Because of the amount of water contained within the Caber floor and polystyrene boards, the pattern of contamination and the incidences of rot, I do not believe that condensation has caused this problem.  No doubt the now high Relative Humidity in the building is contributing to its presence at the moment but this is a separate issue that can be resolved when the main problem is dealt with.                                               

It is my opinion that the damage is being caused either by a failure of the tanking to the rear wall or by a failure of the damp proofing membrane beneath the floor slab. Furthermore, from the advanced stage of the rot in the carpet gripper and elsewhere, this failure occurred some considerable time ago.

I cannot say for sure which of the two faults has actually occurred without further excavation of the floor screeding and perhaps this is now an issue for others to decide. However, should you require a definitive answer, I will be happy to carry out further work on your behalf.                                         

I trust the above is satisfactory for your purposes but if you require further clarification please do not hesitate to contact me.

Surveyor