Mold and Undersized Ducting... options?

[vstech]

OK, you have several problems, and mold is just the visible sign.

your house was designed to operate with 2.5 tons, the ductwork installed reflects this. it's old ductwork, and likely has very poor insulation, and leaks badly into the attic, which draws hot air from the attic and outdoors into the home.

the #1 solution to your situation is getting your home sealed up better, fixing the attic infiltration, and getting modern ductwork installed that has less to no leakage, and R8 insulation with a foil reflective vapor barrier that is sealed. then you can go back to a 2.5 ton a/c and have a comfortable house, with much lower power bills.

everything else is patching a problem, and you need to look at it that way.

[beshvac]

So team two came out today, promptly steered the conversation off of a dehumidifier and right back onto the complete redo of all duct work. While I understand that this is the PREMIUM solution, there a lots of times in life when, for a variety of reasons, options B, C, and D may be preferable. Is this going to be my experience with everyone... "We do it RIGHT or not at all"? I simply am not going to put that kind of money into this house at this point... is there someone else, beside AC companies, I should call? Or some other way to properly say "I am not interested in new ducts, please quote me on a dehumidifier." that allows them to still be professional? A little frustrated, taking days off work to make no progress is adding to the irritation. Any opinions? Thanx guys.

David

Same with my company also, you want it fixed-this is how to fix it right and if you don't want to fix it right we walk. Beware the company that just wants your money and will tell you anything to get it.

The reasons are like others stated above- we want to go in, fix it and move on. Not lets "try this", then "try that", then you're not happy and then its back to the original problem.....

[Shophound]

Thanx Teddy Bear.

The original system was 3 and the house was never less then 80 in the summer, we made the jump hoping to at least be comfortable. We got no warning of the dangers of doing so. The guys who came out the other day told us the ducting was sized for 2 or 2.5, so it appears someone else already upsized before we purchased, and we upsized their upsize, just compounding the problem.

Your OP stated the original size was 2.5; here you stated 3, so pardon my confusion.

Regardless, you got bad advice from whomever suggested an increase in tonnage was required with NO investigation into other potential causes for the existing system to perform below capacity. The harsh truth is most installed residential systems never perform close to design capacity due to poor duct installation and other improper installation practices, in addition to entrenched stupid design decisions like running ducts through an attic that gets super hot in summer. If you live in a primarily cooling climate and have no choice but to run ducts in the attic (due to lack of a basement or crawl space) then the best decision YOU can make as a homeowner is to make the attic cooler year round, along with properly sized, sealed, and installed ductwork. Approaches to cooler attics run from "cool roof" to radiant barriers to spraying foam insulation on the roof deck. The only radiant barrier that impress me are the ones glued to roof decking, so that leaves out most existing homes unless the decking is replaced during a reroof. "Cool roof" approaches are varied and not necessarily all that much more expensive than perpetuating the problem by replacing heat soaking old asphalt with heat soaking new asphalt shingles. Foaming the roof deck and sealing the attic is the most costly but will also accomplish making your house far more comfortable year round.

Of course, if you're not interested in getting your ductwork corrected to proper size and layout, I'm not sure you'd be interested in "building performance remodeling" tips, either, but these posts are read by many and someone may get a good head full of wisdom and find out first hand how smart it really is to focus on the building AND the HVAC as a holistic approach to human comfort.