Residential Fire Investigation - The Importance of Getting the Facts Right

Donan Engineering investigates thousands of fires each year. Of these, almost eighty percent are fires involving residential structures. Fires involving residential structures are clearly different than those in commercial buildings, as the structures, electrical systems, and mechanical systems in residential dwellings are designed and often installed different than their commercial counterparts. As a consequence, special considerations must be made when investigating single-family dwelling fires, including fire dynamics, suppression techniques, fuel types and loads, and the various causes of accidental, natural, incendiary motives, and reasons for an undetermined loss.

Timing can be everything in residential fire investigation. More specifically, how much time elapsed from the fire initiation to discovery and from discovery to the arrival of suppression personnel. Such timing may explain damages, or raise concerns regarding the amount/absence of damages. Key information received from fire department personnel regarding their observations and suppression tactics may be immensely helpful on a case by case basis.

Fire departments may cause fire damage and abnormal burn patterns with regard to the size and location of a fire. Water application and ventilation, if improperly coordinated, can cause rapid fire spread and distorted burn patterns.

Figure 1

Occupant and/or witness interviews are critically important. Fires are frequently linked to a human act, error, or omission, and such human acts may or may not be readily communicated by involved persons. Regardless, it is the fire investigators job to determine whether or not the physical evidence that remains after the fire is consistent with the information conveyed from witnesses. If inconsistencies exist, the question of "why" beckons, and requires an answer of its own.

As opposed to commercial building owners, homeowners are much more prone to have a handyman or “I can do it” attitude, leading them to attempt electrical or mechanical repairs, alterations or modifications that frankly exceed their competence.  The evidence of well-intentioned handymen is unfortunately abundant, and can and does lead to disastrous consequences from time to time.  However, if the well-intentioned handyman himself is questioned, how likely may he be to take responsibility for the error, especially if in his mind this may affect coverage for the loss from his insurance carrier?  It’s a sticky issue, and potentially a problem if one pursues subrogation against an innocent party while the well-intentioned but nonetheless guilty party fails to speak up due to an incorrect assumption on his part.

Figure 2

Smokers don’t cause fires!  Well, sort of.  But their cigarettes, pipes, cigars, ashes, lighters, and matches are all well qualified fire starters.  Candles too, which are often abundant in today’s dwellings, are excellent fire starters when left unattended – and we all know that everyone sits around and watches their candles burn, right?  And what about those stoves and ovens?  Surely no one has ever left home with the burner on the stove or the oven on.  Maybe, but getting an occupant to admit it is another issue altogether.

The bottom line…

Residential fire investigation, while it shares many common traits with commercial fire investigation, is immensely different.  It’s up to you and our fire investigator to work together, not separately, to put the pieces of a loss together.  Consistencies are a great thing and inconsistencies bad.  But inconsistencies can go from bad to disastrous if not caught early in an investigation.  And catching them often can’t occur without knowledge of each residential environment’s uniqueness, accurate information obtained thoughtfully, and cooperation between the Donan fire investigator and you.