This sad saga started in 2001 when Mr. Tompkins decided to replace some of the original wooden windows in his family home in Courtice, Ontario, with vinyl windows. It resulted in a trial that took 20 days intermittently from April 4 to September 25, 2008.

Excessive fear of mould proves ruinously costly for home owner

Tompkins v. Home Depot Holding Inc. (Home Depot)

This sad saga started in 2001 when Mr. Tompkins decided to replace some of the original wooden windows in his family home in Courtice, Ontario, with vinyl windows. It resulted in a trial that took 20 days intermittently from April 4 to September 25, 2008. The facts will be summarized very briefly and incompletely in order to focus on the legal issues.

The Facts

Tompkins ordered eight replacement windows and one patio door from Home Depot, which were subsequently installed by Sunview Home Improvements. Tompkins paid Home Depot $6,269 for the eight windows and sliding door, including installation. Sunview was paid $1,754 by Home Depot.

Shortly after the vinyl windows were installed, Tompkins observed condensation and moisture on the interior surfaces of the newly installed windows. Over a period of three years Tompkins complained to Home Depot about the problems. He maintained that the windows were improperly installed and poorly insulated. As a result, he claimed, cold air entered the home creating moisture damage and mould.

Home Depot and Sunview checked, and found minor evidence of condensation and mould around the Sunview windows. They attributed these problems to the high humidity in the home, unrelated to the installation of the windows.

In November 2004, Tompkins retained an expert to conduct an air quality test. The expert found a small amount of fungal growth and water staining on wood framing surrounding one of the new windows, and low concentrations of fungi in the residence. Another expert found the window installation to be improper. He recommended that the windows be re-installed.

Throughout 2004 and the spring of 2005, Tompkins removed trim, insulation, and other materials around the windows. He re-insulated all but one of the windows. The condensation and moisture problems remained. In April 2005 Tompkins called back the mould expert to conduct further testing in his home.

The expert confirmed the presence of toxigenic stachybotrys mould in a bedroom. Tompkins moved his family to a hotel and went to work on his home. The family stayed at the hotel for 79 days while he stripped the interior of the house to the wall studs. All drywall, insulation, flooring, duct work, ceiling and carpeting in all but two of the rooms in the basement were discarded. He ripped out the entire kitchen, and got rid of all the appliances, tables, chairs, mattresses, TV and stereo. All of the family’s bedding and clothing was thrown out. The new windows were replaced.

The remediation was financed initially using the Tompkins’ savings, and borrowing money from family members. Then the mortgage on the home was refinanced. Once those funds were exhausted, Tompkins used all available credit on a large number of credit cards. As debts increased, he obtained additional credit cards and increased credit limits on existing cards. In order to meet increasing monthly minimum payments, he used cash advances from some credit cards to make minimum payments on other cards.

Were the Windows Negligently Installed?

Justice Sosna of the Ontario Superior Court of Justice found that Sunview owed Tompkins a duty of care to perform the installation of the windows according to the standard of a reasonably competent window installer. He also found that Home Depot owed Tompkins a duty of care.

The judge heard conflicting expert opinions. He accepted the opinion of Tompkins’ expert that the windows were not properly set within the wall cavity, and that the cavity around those windows was insufficiently insulated. He also found that the Home Depot inspectors who checked the installation lacked training, expertise, and knowledge of proper window installation. Lacking such knowledge, they relied exclusively on the opinions expressed by the owner of Sunview, the very person who installed the windows.

Subsequently, Home Depot did obtain an objective assessment from an expert who recommended that the windows be replaced and re-installed. Home Depot ignored this report. As a result, no steps were taken to adequately address or remedy possible deficiencies in the Tompkins’ window installation.

The judge concluded that Sunview breached its duty of care, and so did Home Depot.

The Legal Test for Causation

For the defendants to be found negligent, the plaintiffs must provide proof of a causal link between the breach of standard of care by the defendants and the harm suffered by the plaintiffs. Therefore, the crucial next question facing the court was whether the breach of duty by Home Depot and Sunview actually caused Tompkins’ loss.

Prior to the installation of the windows, Tompkins had not experienced any problems with mould. Once the windows were removed and replaced, the moisture and mould problems were corrected. Counsel for Tompkins therefore argued that a presumption of negligence should be found against the defendants.

Home Depot and Sunview submitted that if Tompkins has suffered any harm, it was caused by pre-existing high humidity levels in the home, unrelated to the installation of the new windows.

Justice Sosna addressed the two legal tests that govern the determination of causation.

First, under the “but for” test, the plaintiff must prove that “but for” the breach of the standard of care by the defendant, the injury or harm to the plaintiff would not have occurred:

The “but for” test is intended to insure that the Plaintiffs is compensated for negligent conduct only where there is a substantial connection between the injury and the defendants’ conduct. Where the injury or harm may be due to other factors unrelated to the defendants’ conduct, no
liability can be found.

Second, if the plaintiffs cannot meet the requirements of the “but for” test, they may be permitted to provide proof of causation on the “material contribution” test. Only in extraordinary or exceptional circumstances will the law recognize an exception to the “but for” test and apply the “material contribution” test:

The plaintiff must prove either the “but for” test or the “material contribution” test on the balance of probabilities.

Findings of Causation

Justice Sosna found the evidence of the expert called by the defendants regarding causation to be “logical, persuasive and credible”.

The expert testified that condensation is the process by which water vapour is transformed into visible water droplets. It occurs when moist air is cooled to the point that the relative humidity of the air is increased to 100 per cent, commonly known as the dew point. This happens when moist indoor air reaches the cold windows. Condensation on the windows is not aggravated by cold outside air entering the house because the outside cold air contains less moisture than the interior air, so the air in the house actually becomes drier.

The expert identified a number of structural deficiencies in the Tompkins’ residence, which could allow outside moisture to seep into the walls of the residence: mortar droppings bridging the wall cavity, plugged weep holes, and the absence of properly installed through-wall flashing. All of these deficiencies, individually and in combination with interior high humidity levels, can create the necessary environment in which moisture in the wall cavities may result in mould growth.

Tompkins testified that, when he removed the drywall and vapour barrier in the bedrooms, he found areas of mould on the exterior wall sheathing. However, the windows were on the north walls of each bedroom and any mould that was detected in the cavities was on the east or west walls of those bedrooms. The defendants’ expert testified that moisture is not alive and cannot jump. Therefore, he found no relationship between the windows and the mould.

The court also rejected Tompkins’ additional theory that the improperly insulated windows caused moisture to accumulate in the cavity around the windows leading to mould growth in the wall assemblies. The expert testified that inadequate application of insulation around the windows would not result in the formation of condensation in the cavity surrounding the window. Tompkins himself had testified that he re-insulated the Sunview windows shortly after their installation in 2001. However, as late as 2004, the re-insulated windows continued to exhibit moisture and condensation.

Justice Sosna found that the plaintiffs had not proven causation against the defendants. He dismissed Tompkins’ action against both Sunview and Home Depot.

Assessment of Damages

Although he found that the plaintiffs had failed to prove causation, the court still had to undertake a review of the claim for damages in case there was an appeal.

Tompkins sought damages of $550,000 for costs incurred in the remediation of the home and replacement of household contents. Justice Sosna agreed with the defence position that, given the relatively small amount of mould discovered in the house, it would not be foreseeable that Tompkins would vacate, demolish and renovate the entire home, discard most of the personal property, and as a result incur massive debt, laden with significant compound interest and penalties.

The judge found Tompkins’ response to the presence or threat of mould to be unnecessary and extreme. If causation were proven, he would assess damages of $15,747 in total for the removal and replacement of drywall, insulation, and vapour barrier where mould was located, the cleaning of the mould and repainting of the affected areas, the reinstallation of the windows, the replacement of carpeting, and the expert report.

Ontario Superior Court of Justice
   Sosna J.
   January 2, 2009