Basements in homes built prior to the new millennium were typically not designed to be used as additional living space. In most instances, the foundations are not waterproof, and there is no vapor barrier beneath the concrete flooring. The resultant environment generally exists in a state of unreasonably high humidity, and elevated mold spore counts; with a propensity for basement flooding from water infiltration during heavy rains as well as rapid snow melts.
Cellulose, Moisture & Mold Contamination
If considering construction of a finished basement in a home that was not designed for this improvement, careful consideration of the utility weighed against the increased likelihood of basement flooding and/or mold damage is strongly suggested. The insidious nature of water almost ensures the presence of progressive mold damage if conventional building methods are deployed. Mold is ubiquitous, making contamination dependent upon the presence of only two common conditions: cellulose, and moisture. Much like mold, water and cellulose are omnipresent.
Water is a daily constant that naturally exists in solid, liquid, and gaseous states, the quantity of each form dependent upon ever-changing atmospheric conditions. We are surrounded by a myriad of mechanical controls designed to keep water at bay, and artificial conditioning systems that are often designed to control humidity. Such systems and devices are periodically overwhelmed, and the result is basement flooding and/or mold contamination.
Cellulose is built into every facet of our lives. Cellulose based products include, wood products, paper products, many textiles and much more. Traditional building materials are laced with cellulose containing substances that will support mold growth when holding as little as 16% moisture content. Virtually all cellulose based building materials are hygroscopic, making moisture content dependent not only upon physical saturation, but also atmospheric conditions.
Absorption, Adsorption & Moisture Content
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment. Defined as a chemical or physical phenomenon in which the molecules, atoms and ions of the substance getting absorbed enters the bulk phase (gas, liquid or solid) of the material in which it is taken up, absorption is the condition in which something gets mixed or absorbed completely in another substance.
Conversely, adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. This process differs from absorption, in which a fluid (the absorbate) is dissolved by or permeates a liquid or solid (the absorbent). Adsorption is a surface phenomenon, while absorption involves the whole volume of the material, although adsorption does often precede absorption. The term sorption encompasses both processes.
The hygroscopic nature of traditional building materials via both absorption and adsorption, makes the likelihood of mold contamination in retrofitted finished basements endemic. There are building techniques and conditioning steps that can be adopted to lessen the likelihood of finished basement mold contamination, but such methods and machinery become financially constricting.
Physical & Mechanical Protections
Wood and wood-based products, like many natural materials, are hygroscopic; it takes on moisture from the surrounding environment. Moisture exchange between wood and air depends on how much moisture the air is holding, the temperature of the air and the current moisture content of the wood. The physical relationship between atmospheric conditions and moisture content of hydroscopic materials is outlined as it relates to water damage restoration in our blog article VAPOR PRESSURE & WATER MITIGATION. The following excerpt outlines the relationship between relative humidity (RH) and moisture content of hygroscopic materials.
‘The reason RH is used in restoration is that hygroscopic materials have an equilibrium moisture content that is mainly determined by RH. In simplest terms, when RH is low, materials will generally lose moisture. When RH is high, especially above 60 percent, materials will generally gain significant moisture. When conditions exceed 60 percent RH, the structure is more likely to suffer secondary damage.’
Metal studs, paperless drywall, composite trims, and non-cellulose-based floorcoverings are among the building materials to be considered if converting a traditional cellar to a finished basement. It should be noted that eliminating all cellulose based building materials is unlikely as joist systems and stairwells are traditionally constructed of wood. Furthermore, contents within a finished basement should be carefully considered as furnishings are customarily constructed using cellulose laden natural fibers.
Mechanical controls, such as dehumidification, French drains, sump pumps, as well as enhanced exterior guttering and grading should also be considered. Although these precautions can reduce or eliminate atmospheric conditions conducive to mold contamination, such safeguards are susceptible to failure. There is a multiplicity of occurrences that could overcome any safeguard established. Excessive rains and snow melts can overwhelm mechanical controls, machinery can malfunction, plumbing can fail, drainage systems can clog, guttering can become dislodged or blocked and more.
Will Homeowners Insurance Cover It?
Homeowners insurance policies can cover some of the possible outcomes, others have limited or no coverage depending on source, duration and addendums that have been purchased and are in place. Our blog article, WATER DAMAGE VS. FLOOD DAMAGE, delves into the question of coverage, which is dependent on source. The following passage details an almost universal truth:
‘Most homeowner’s insurance policies cover water damage caused by system failures within the home, but virtually every homeowner’s insurance policy has stated exclusions concerning surface water runoff, also known as ground water.’
In addition to source, duration of a water event is taken into consideration and can lead to denial if it is determined that the damage in question resulted over an extended period. The following quotation from our blog article WATER DAMAGE DURATION & COVERAGE, outlines coverage requirements with regard to the damage interval.
‘Ongoing water damage is not usually covered. Insurance policies generally have qualifying statements that require water damage to be sudden and accidental, with continued exposure generally being 14 days or less. Policies that would otherwise cover such an event, may deny a water damage restoration claim if the event has continued beyond the ascribed time limit.’
It should be noted that there are anemic insurance policies that have no water damage coverage whatsoever. Water damage is commonplace, opting out of this coverage in favor of insignificant reductions in monthly premiums is short-sighted and property owners who choose this option are often blindsided by a disastrous financial depletion of their own making.
Should I Have My Basement Finished?
When considering having a basement retrofitted to create additional living space, the question of utility is pertinent, and the answer is intensely personal. Utility is defined as the state of being useful, profitable, or beneficial and should be carefully considered before committing to such an expensive and damage prone undertaking. Finishing a basement that was not designed for habitation, substantially increases the possibility of basement flooding from any number of sources as well as mold contamination brought on by water events and unfavorable atmospheric conditions.
Systems established to reduce the possibility of basement flooding and mold damage do not guarantee a ‘trouble-free’ solution no matter the depth of redundancy. ‘Probability’ refers to the chance that a particular outcome occurs based on the values of parameters in a model, while ‘likelihood’ refers to how well a sample provides support for particular values of a parameter in a model. The question of feasible outcomes can be endlessly contemplated yet yield no answers.
Basement Flood Restoration
Basement flooding in Philadelphia? Property Recovery 911 offers professional Basement Flood Cleanup in Philadelphia and the surrounding counties. We are prepared and on call 24 hours a day, 7 days a week to dispatch a rapid response team who can be on your location within 1 hour protecting your interests. Contact us at (267) 808-7200 for basement flood restoration. We can prevent or alleviate the devastating effects of water damage and to safely dry, deodorize and disinfect the affected areas.