Unintended Consequences From Home Improvements
Often times, our home inspection reports are used by the new buyer as a punch list for their new home. More insulation, an improved bathroom fan, and falling crawlspace insulation are common discoveries in our inspections. What could go wrong?
Improved Bathroom Fan
The bath fan is hardly working and surface mold is visible on the walls of your primary bathroom. Replace the fan, right? Sure. It will remove excess moisture that is allowing that mold to grow. Not only do you replace the fan, but let's say you increase the power of the fan to pull more air out. That will fix the mold problem, but will create an energy problem. When a basic bath fan is functioning, it is pushing warm air out. Your home requires replacement air, otherwise it would implode (not likely). Replacement air? Imagine emptying a jug of milk. The milk gurgles out of the spout as air rushes in to replace the same volume of milk that is leaving the jug. Same idea, but the replacement air in February for your 70 degree vented air is only 10 degrees. This cold air is coming in through all the gaps and cracks in your home (windows, door frames, dog doors, kitchen vents, etc.) Before you go crazy on replacing with the Ferrari of bath vents, consider the unintended consequence of heat loss. Some simple solutions: replace the fan with just what you need, not more (60-100 CFM is normal) ; install a timer for the bath fan so the fan is not operating when not needed; install a hydrostatic version of the fan to only operate at specific humidity levels; or hire a professional to install an Energy Recover Ventilator (ERV). These will minimize those unintended consequences and likely fix the surface mold issue for good.
Adding insulation is a great way to improve the energy efficiency of you home. More is better, right? Careful on that one. Depending on the age of your home, you may or may not have attic ventilation. If your attic cannot breath, heat and moisture builds up and cannot escape. This may cause mold, rot, and will reduce the life of your roofing shingles. Often times, a DIYer will add insulation without realizing they are covering the soffit vents placed in the eves. The soffit vents allow the ridge vent (at the top, or "ridge" of the roof) to exhaust the heated, high-moisture air. Excessive insulation may keep heat in, but will negatively impact your attic and roof covering if installed improperly. We also see this when homeowners attempt to minimize pest or rain entry through the gable vents and permanently cover them. Bad idea. If unsure of how to add insulation, use a qualified insulation group.
Missing Crawlspace or Ductwork Insulation
We commonly find uninsulated or poorly insulated areas beneath the first floor, specifically between the floor joists and around ducts from a forced hot air furnace. Many new homeowners simply place fiberglass batting insulation between the floor joists and then wrap the ductwork with insulation in an attempt to reduce energy costs. What is often forgotten is the lack of insulation may be keeping the crawlspace above freezing by inadvertently heating the space. Monitoring the crawlspace temperature is critical after insulating. If you find the crawlspace teeters on freezing, your pipes are in danger of freezing as well.
Matt & Matt