Subrogation Flood Issues

Toxic Mould leads to £10 Million Warranty claim

      In 2007 Building Forensics were asked to investigate possible health issues regarding a small patch of black mould in a three year old luxury apartment in south London. The findings resulted in possibly the biggest ever NHBC warranty claim which currently in 2009 is in excess of £10,000,000 with personal injuries likely to follow. While this particular project affected a new penthouse, similar problems existed throughout the building and can affect any new, old or renovated home. Poor design, or build (building defect) and of course flood affected homes can trigger the substantial health and construction problems identified in this article.

Summary

The current quest to reduce carbon footprint, reduce heat loss, increase insulation and reduce ventilation (air leaks) has resulted in the continuing increase in Tight Building Syndrome. This is where the inhabitants suffer ill health and a variety of maladies including flu like symptoms, depression and in some cases major disease such as cancer or tumours. The average family of four produce 20liters of moisture a day from cooking, washing, breathing and without adequate ventilation the moisture is absorbed into the chalk and paper construction material known as plasterboard. Plaster board a major component of all construction is the ideal growth  factor for mould and what has been identified as “Toxic mould” the genus most likely to be found in the indoor environment. There are over 100,000 types of mould but only a handful identified as toxic. These unfortunately are the ones found to grow in the home and generally on the paper backing of plasterboard, usually in the cavities.

Liability and Subrogation Issues

The following outline shows typical problems which can affect home owners, tenants and employers. The implications of building decay and occupant health are obvious and can be aligned to asbestos. The fault of exposure to “Toxic Mould” can lie with architects, surveyors, builders and designers. Equally incompetent flood restoration and life style issues can be major component in liability. The investigation into cause and effect is a key issue although investigation and evidence gathering can cost as little as £1000.

Investigation

The client had health concerns over a small patch of black mould in the hall ceiling and asked for sampling and health assessments. A sampling hypothesis following internationally recognised protocols was developed to identify cause and effect of potential moisture problems and types of mould and relevant health concerns.

Infrared Thermography

A scan of the property showed dramatic gaps in insulation and identified thermal bridging most likely to cause condensation, and resultant mould growth within cavities.

Moisture mapping

Ultrasonic and conductive moisture meters were used to identify high moisture content of walls ceilings and floors. This identified wet patches from leak, condensation and cold bridging issues.

Laminar & Turbulent air flow

The variations in temperature and moisture within interstitial cavities, the building envelope and general voids raised concerns of major building defects. Anemometers and manometers were inserted into electrical fitting plasterboard housings and used to assess the pressure differentials. This showed the inspected areas alternating from positive to negative pressure. This evidence pointed to major failures of the building envelope.

Intrusive Investigation

From the forgoing measurements and general concerns small areas of plasterboard were removed to allow visual inspection. In light of the forgoing the following areas of concern were raised with our client (the homeowner) which needed to be assessed by the builders and NHBC under the terms of their warranties:

• Facing bricks stuck directly onto OSB
• No Vapour barrier or drainage plane on external facade
• Missing wall insulation
• Visible gaps between window frames and walls
• Missing lintels
• No insulation or adequate protection to steel support structure
• Missing Fire stops
• Cold bridging of balcony and internal floors (continuous cast)
• Vapour barrier on wrong side
• Windows inserted into OSP apertures without adequate or indeed any proper weatherproofing or sealing.
• External Air flow directly into building and construction envelope through major leakage points in roof and façade generally

Floor

The concrete floor was covered in laminate wood flooring which showed signs of swelling and cupping. Sections were removed to show that the screed saturated, Moisture sleeves were inserted to assess compliance to British Standards and the floor was found to be saturated. Leaks from windows and cold bridging were identified. This was exasperated by the 40mm of foam insulation under the 75mm screed and acted as a reservoir.

Walls

The plasterboard walls fixed onto metal studding but touched the wet floor in places causing wicking (capillary action). This resulted in mould growth in the internal cavities on plasterboard backing paper.

Pre fabricated pods

Part of the initial construction involved the use of pre constructed drop in pods for the kitchen and bathroom. These pods built within a metal frame allowed no access for inspection. Moisture Mapping, visible distress and mould were adequate pointers to undertake intrusive investigation which identified leaks form various pipe couplings, drainage joints and general seams.

Mould Sampling

Bulk samples were taken from visible mould growth. Air sampling designed to identify viable and significantly non viable mould spores,  was undertaken throughout the property and common parts.

Sampling Results

As was expected from long term water ingress or condensation, Cladisporium was abundant but the significant health issues were from Stachybotrys, and Penicillium/ Aspergillus. These moulds have been identified as potential triggers for a variety of health issues including :

• Asthma
• Brain tumours
• Lung and liver cancer
• Depression
• Flu like symptoms

Current issues

The building is currently under major repair with many families moving out to facilitate remediation and retro fitting of construction shortfalls. Major decontamination and clearance has been under taken by Building forensics and the 999team Ltd. The cost is now well over £10 million and steadily rising.

Supporting Evidence and Scale of the problem

In June 2008 Sir Michael Pitt published his damming report into the insurance and restoration industry response to flooding and its failures of 2007. In the section on recovery he points to the fact that insurers and contractors have no uniform approach to recovery or restoration. Most importantly he makes particular comment on the health and safety issues regarding habitability post flood event. He cites toxic mould, depression and other health issues with specific examples of how depending on where you are or who you talk to how you are advised to leave or stay at the property. The actual restoration process was also found to be a matter of pot luck with no clear objectives or protocol from either claims management or contractors on how to dry or restore flooded buildings. The scale of flood claims or increasing contractor incompetence escalates the problems of the insured but also increases the opportunity for competent advice or support.

Recent contractor inspection and forensic audits have revealed the following issues:

• Failure to comply with asbestos legislation resulting in contamination spread. (this is often from uncontrolled Artex removal)
• Toxic mould caused by long term water damage and failure to control the environment, resulting in serious health issues.
• Total and unnecessary gutting of buildings.
• Failure to expose wet or contaminated areas resulting in sanitation issues.
• Failure to decontaminate properly usually the result of only spraying chemicals.
• Failure to contain the damage resulting in secondary damage far away from initial damage, (typically evaporation and condensation/mould issues upstairs).

Apart from the domestic property claims, the commercial world was faced with even worse contractor skill sets. Invariably businesses are left for days or weeks before loss adjusters turn up and invariably this delay results in escalating damage caused by corrosion, condensation and massive unnecessary secondary damage.

Throughout the Pitt Report he identifies failures in drying and mould as major issues. It is interesting to note that training in the UK revolves around American drying protocols and the UK industry failed to notice different construction techniques, hence buildings are wet for months and years. New drying techniques again introduced from the USA may provide faster results but will also bring their own problems. From forensic or live audits I  undertook  from Lewes in 2001 to Carlisle  and Sheffield-Hull and Gloucester in 2008 every single claim was found to have major problems caused by claims management or contractors, and  drying or sanitation certificates proving worthless.