Old duct work is leaking
I live in a 1961 year old peer and beam one story house in Dallas. about 3500 sq foot. I platoon living here for 15 more years then it will bulldoze it for a new house when I sell.
Lots of dust penetration, Have pella windows and doors. dust is coming from all of the air system. The returns under the floor space that have been newly mastic and sealed. Two main units are in the hallway- 2011 Traine system. Office new in 2014 up in attic.
The majority of the dust is coming in from the old metal duct work(attic) with wrapped 1961 fiberglass insulation that is not intact in some places- gaps. Have done thermoimaging and it shows where the duct work is leaking- and sucking in old original gray attic insulation into the house. And in some places you can visually see it.
I need honest advice.
3 bids AC people and 1 from Insulation co.
One advised to do an attic rehab that included removing the old metal duct fiberglass insulation, patching/mastic and then spraying with closed cell to insulate and re-seal.R- 13, among sealing all seams/open areas of pipe electrical insulation, covers for the can lights. Sealing pocket door’s, top plate sealing etc. First step was to remove the old nasty(it is really bad and filtering into the house) attic insulation with rodent and pest droppings then reinstalling with cellulose R38. Along with spray foam on the vaulted ceilings “knee walls” that butt up to living space. (includes attic tents for attic access). Will the closed cell foam rust my metal air duct’s? Estimate $18,500 to 20K
Second is to remove all the old hard pipe duct work, add new R-8, two new plenums with dampers, (third unit is office only and new in 2004), sealing boots and changing vent registers if needed. Add in 3 Air ranger air cleaners. Remove and reinstall 18 inches of cellulose insulation and 6 in batting insulation on the vaulted walls. Estimated price $16,701. Does not include attic door tents (will need to add) No can light covers
Third bid- aeroseal attic duct work $7800, If mastic seal on exterior is needed of the duct work remove and replace old insulation at 5 foot junctions additional $4704 add in Micro Power Guard air purifier each unit x 3 for a total of $2625. $15,129. Does not include any insulation removal or re-install.
Waiting on the blow in insulation bid. Might use fiberglass vs. cellulose?
Thank you for your help.
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