All these conditions are treatable and preventable.Wood destroying fungi and mold can be treated. The mold/mildew can be removed with products such as Shockwave and the wood destroying fungi can be treated with BoraCare or Timbor. Re-working or replacing the ducts can be more challenging. They need to be secured above any high water line. If sufficient room is not available, we will need to modify the equipment and duct placement which may require different equipment or remodeling the home to accommodate the equipment/ducts. Unfortunately, there is no shortcut to this process.
Many will advise you to encapsulate the crawlspace but that is not the best option.While this may be a good option in drier climates, it almost never is in Florida. Unless you can stop the water infiltration into the crawlspace (mostly impossible), in time the water will float or damage the visqueen barrier rendering the encapsulation obsolete. Further, you will be required to install mechanical dehumidification as you have created a whole new ecosystem in this “terrarium.” You still have hot, moist, humid air in the crawlspace which will create condensation so unless you are mechanically dehumidifying the area, you will still have a moisture issue. If you install a visqueen vapor barrier beneath the floor joists this condensation will form and deposit moisture between the plastic barrier and your wood joists/flooring. You have really not accomplished anything and now you have a extra mechanical systems (dehumidifier and sump pump) to maintain and eventually replace. It is a short term solution.
Is there anything that does work?Yes, but it will always require modification and money. However, the money you spend will be a long-term solution. You can’t change or alter rising water in most cases, so you must be able to control it when it does occur. Improving site and crawlspace grading is first and foremost. Most people have never investigated their crawlspace let alone clean it up. We find trash piles, debris piles, rotted wood, old furniture and more in crawlspaces. Plumbers and AC contractors are notorious for digging holes to make their work easier and these holes fill up with water. Over 80% of the crawlspaces we inspect do not have any floor insulation. The crawlspace should drain away from the home. You may need some drainage piping and even a sump pump. The second biggest issue we find is improper ventilation. Building code requires a minimum of 1 square feet for each 150 square feet of under-floor space. Further at least one vent should be within three feet of each building corner. There are different ways you can achieve this but meeting the minimum code requirement is generally not enough ventilation for our Florida homes. Personally, I believe you need to triple this sizing recommendation. The more air flow, the better. Building codes also does not take into account if we have restricted air flow due to being in a dense, urban setting. The code assumes your home receives air flow from all directions and that is just not typical in a city type setting. Another issue we find is people blocking the ventilation with dense shrubbery which further restricts air flow. Keep the vents open and clear of any vegetation. Insulate the floor and seal all gaps/cracks/penetrations into the floors especially around ducts and plumbing connections. Remember, each time your air handler turns on it is creating a draw from your crawlspace and it is pulling that dusty, damp air from the crawl into your air stream. Re-work AC ducts to get them off the ground and above any high-water mark. If that is not feasible, you need to consider modifying the HVAC system to get the ducts out of the crawlspace. This may be expensive and you may need to plan this in stages.
Have your home inspected by an indoor air quality expert.If you call a “crawlspace company,” all you will hear is “encapsulate” but that is rarely the best long-term solution. It also is not cheap and encapsulation with mechanical controls may cost as much, or more, than re-working your AC system to get it out of the crawl. If you are in the Jacksonville or Orlando areas, give us a call to schedule an inspection. We don’t sell encapsulation or anything other than quality air consulting.