I'm hoping someone can give me a little advice on what to do regarding a humidity / cooling imbalance I'm trying to solve. This may be a little lengthy but I'm hoping someone has a minute to give me their opinion or suggestion on what to do. I'll try to make a long story as short as possible.
I purchased my house in May 09'. It has a basement that's approx 600 sqft with a bathroom and a small closet. The first floor is approx 1800 sqft with 3 bedrooms, 2 bathrooms, kitchen and dining area, and a sun room, the living room has an 18' vaulted ceiling. The second floor consists of a single room loft approx 150 sqft over the living room. I have 2 Goodman gas packs, 1 2 ton, the other 3.5 tons on opposite ends of the house. The house is built on a conventional foundation.
The basement is where I'm having the biggest headache. When I first purchased the house the basement had a musty, mildew type odor that my realtor conveniently contributed to the fact that the house had been vacant for about a year. You could feel the humidity on your skin it was so damp. I figured that once some air got circulated through the house it would improve. Three months later there was no improvement. After some looking around I found that the registers that I thought were returns were in fact supplies. I had a total of 4 registers, 2 at floor level, 2 at ceiling height. No return at all. However the stairwell was opened to the upstairs. The basement consistently stayed about 15 degrees cooler than the upstairs.
In October the toilet in the basement "backfired" and flooded the entire room with contents that belonged in the septic tank. Needless to say, I gutted the entire basement down to the slab and cinder block walls and had the 70's paneling and carpet hauled to the curb. I had the room professionally cleaned, sterilized and dried. Hoping to prevent the moisture, mold and musty smells from returning I did everything I could think of to prevent water vapor and odors from coming in from the crawlspace. I sealed the cinder blocks with "Thoroseal", framed in new walls and sealed the studs with kilz, applied a 6 mil vapor barrier around the entire room, sheetrocked the room with moisture / mold resistant drywall and tiled the floor. Additionally, I had a door framed in at the bottom of the stairwell to keep all the cool air in the house from settling in the basement. I was hoping this would take some of the demand off of the units since they couldn't keep the first floor cool on hot days running constantly, yet the basement stayed the same 15 degrees cooler than the upstairs regardless of the outside temperature. My thought was that if I simply added a return to the basement it would pull the damp, cool, stagnate air out, circulate it through the system dehumidifying it, and redistribute it throughout the house. I thought this would solve the humidity problem. I had three contractors come out and give me their opinions and quotes on the work. Two said it wouldn't work but would be happy to install the returns if that's what I wanted. The third said he thought it may work but I would need a continuously operable dehumidifier. My HVAC knowledge is extremely basic at best. A friend of mine that does commercial HVAC work suggested that I go with a ductless split system since many of them have a full time dehumidifier function and due to the fact that I don't need full time climate control in the basement. I really don't have any problem keeping it cool, it's more the uncirculated, humid air that I need to alleviate. It's beginning to get warmer outside and I need to make a decision on what I'm going to do. I want to do it once, the right way, the first time. I have invested a fair amount of money into turning this room into a home theater, I can't afford to throw money at something that may or may not work. I have disconnected the supplies at the plenum and the places where registers were have been sheetrocked over. Not a major issue to put the registers back in if needed. Did I make a mistake by adding the door? Can someone explain to me why adding a return won't work to remove the humid air? What are you pros suggestions? I greatly appreciate your time and input, hopefully I can come up with a solution that works the first time. Thanks, Brian
I purchased my house in May 09'. It has a basement that's approx 600 sqft with a bathroom and a small closet. The first floor is approx 1800 sqft with 3 bedrooms, 2 bathrooms, kitchen and dining area, and a sun room, the living room has an 18' vaulted ceiling. The second floor consists of a single room loft approx 150 sqft over the living room. I have 2 Goodman gas packs, 1 2 ton, the other 3.5 tons on opposite ends of the house. The house is built on a conventional foundation.
The basement is where I'm having the biggest headache. When I first purchased the house the basement had a musty, mildew type odor that my realtor conveniently contributed to the fact that the house had been vacant for about a year. You could feel the humidity on your skin it was so damp. I figured that once some air got circulated through the house it would improve. Three months later there was no improvement. After some looking around I found that the registers that I thought were returns were in fact supplies. I had a total of 4 registers, 2 at floor level, 2 at ceiling height. No return at all. However the stairwell was opened to the upstairs. The basement consistently stayed about 15 degrees cooler than the upstairs.
In October the toilet in the basement "backfired" and flooded the entire room with contents that belonged in the septic tank. Needless to say, I gutted the entire basement down to the slab and cinder block walls and had the 70's paneling and carpet hauled to the curb. I had the room professionally cleaned, sterilized and dried. Hoping to prevent the moisture, mold and musty smells from returning I did everything I could think of to prevent water vapor and odors from coming in from the crawlspace. I sealed the cinder blocks with "Thoroseal", framed in new walls and sealed the studs with kilz, applied a 6 mil vapor barrier around the entire room, sheetrocked the room with moisture / mold resistant drywall and tiled the floor. Additionally, I had a door framed in at the bottom of the stairwell to keep all the cool air in the house from settling in the basement. I was hoping this would take some of the demand off of the units since they couldn't keep the first floor cool on hot days running constantly, yet the basement stayed the same 15 degrees cooler than the upstairs regardless of the outside temperature. My thought was that if I simply added a return to the basement it would pull the damp, cool, stagnate air out, circulate it through the system dehumidifying it, and redistribute it throughout the house. I thought this would solve the humidity problem. I had three contractors come out and give me their opinions and quotes on the work. Two said it wouldn't work but would be happy to install the returns if that's what I wanted. The third said he thought it may work but I would need a continuously operable dehumidifier. My HVAC knowledge is extremely basic at best. A friend of mine that does commercial HVAC work suggested that I go with a ductless split system since many of them have a full time dehumidifier function and due to the fact that I don't need full time climate control in the basement. I really don't have any problem keeping it cool, it's more the uncirculated, humid air that I need to alleviate. It's beginning to get warmer outside and I need to make a decision on what I'm going to do. I want to do it once, the right way, the first time. I have invested a fair amount of money into turning this room into a home theater, I can't afford to throw money at something that may or may not work. I have disconnected the supplies at the plenum and the places where registers were have been sheetrocked over. Not a major issue to put the registers back in if needed. Did I make a mistake by adding the door? Can someone explain to me why adding a return won't work to remove the humid air? What are you pros suggestions? I greatly appreciate your time and input, hopefully I can come up with a solution that works the first time. Thanks, Brian
