The Quick Green Blog - An Appraiser View

Air quality, often the most-cited important feature of Green Built Certified Homes, is achieved through capturing, controlling, and diluting the source through filtration.

Healthy indoor air quality is important for energy efficiency and comfort, and is accomplished with a tight building envelope. Air filtration through walls, for example, contributes to energy loss and is also a source of mold when warmer conditioned air condenses as it reaches a cooler surface in the wall cavity.

A tight building shell does create the need for an intentional means of introducing fresh air into the living space. Introducing air into the home in a controlled manner has both an energy and IEQ advantage.

The first step involves calculating the building's heating and cooling BTU load requirements.  Then the type and size of HVAC equipment is determined to meet that load.  Finally, the supply and return ductwork is laid out and sized for the structure.

When installing gas furnaces or fireplaces use direct-vent equipment and/or install induced mechanical draft in a combustion closet to minimize the quantity of combustion-generated pollutants entering the home and the unnecessary loss of indoor air to support these devices.

Tip: Look for Energy Star certified HVAC units with high SEER, HSPF, and AFUE ratings to minimize utility expenses and reduce consumption of natural resources involved in energy generation.

INDOOR AIR QUALITY VERIFICATION BY THIRD PARTY INSPECTIONS

Inspectors verify:

• Duct installation and sealing
• Building envelope air sealing details (i.e. sealing utility transits in wall plates)
• Proper insulation installation: Cut accuracy, cavity fill, gaps, voids, or compression
• Sealed crawl and attic ventilation
• Windows and doors are flashed, caulked, and sealed properly
• Direct vent equipment and perform door pressure
• Proper balance of exhaust and supply fans and energy recovery ventilators

Appraisers have encountered difficulty under new rules introduced since the mortgage meltdown.  The Housing Valuation Code of Conduct (HVCC) now restricts direct communication between appraisers and lenders/processors.  This has led to the creation of third-party intermediaries that manage the information flow.  This is intended to eliminate undue influence, but often inhibits necessary communication.

Particularly for green properties, where there is a need for clear communication of features and detailed specifications, this can create a problematic situation.  But fear not, there is NO RESTRICTION on my being able to obtain information from the other parties (builder, realtor, seller) - only the lender!  So it becomes really important that I know who will have the details I will need to conduct a truly informed inspection. 

Many people have pointed out that much of the real value of a green home is "invisible" - but not intangible.  Having the right resources at hand is critical to achieving the proper value.  As I have pointed out before, we have a real need to standardize how this information can be captured, recorded, and transferred.  But in the meantime, I am more than happy to talk to you (unless you're the lender!)