Add AC to existing Home no room for ductwork on 2nd floor

[gdtrfb]

We recently purchased our first home in MA near NH border. The house is a cape built in 1965 with window dormers in front, shed dormer in rear. No attic, crawl space is about 16" with lots of blown in insulation. An addition was built in 1990 which was a foyer connecting addition to side of existing house with two car garage and large room above it. Off of the foyer is a 3 season porch. The heating source is a oil burner with forced hot water and no existing air conditioning system or any duct work.

Through my novice research, I was thinking that a high velocity mini-duct system would do the trick.

Have called several contractors that were referenced from spacepak and unico that also did traditional central air to find best solution. Two contractors have come by, two more scheduled for later this week, waiting to hear from another.

Both of the contractors said I do not have the space to run any ductwork in the original 2nd floor to do either traditional AC or hi-velocity AC. The first professional sais that to create space for duct work would become price prohibitive.

The family room above the garage has vaulted ceilings with crawlspace running the outside of the side of the house.

They both suggested a mini-split system for the master bedroom and one for the family room upstairs and central air for downstairs. They both recommended the Mr Slim systems by Mitsubishi. Upstairs has a laundry room off a hall way that connects the family room to the second bedroom and there's a small full bath between the two bedrooms where the original stairs went.

Downstairs consists of the foyer which has a full bath next to it and leads to the 3 season porch in the back, the stair case to the family room over the garage on the right and the kitchen on the left. The first floor of the original house consisted of a living room to the front left, dining room to the front right, bedroom/office to the rear left, kitchen to the rear right and a half bath in the middle of the back hall connecting the different rooms.

There is a full unfinished basement where duct work could be run for the first floor.

The price of doing central AC downstairs and the two mini-split systems upstairs is higher than what I was planning on spending. I'm not opposed to doing it right, might have to wait a year or two for that solution.

After finding this site and reading a bunch of posts I was wondering about other split systems (Fujitsu, Daikan...) that one could attach several indoor units to one or two compressors. I don't think we need to cool the dining room and living room. For the 6 to 8 weeks we really need AC, we can live in other parts of the house... Downstairs, I would like to cool the office, kitchen and three season porch. The office has a door and can be closed, same deal for the three season porch. If we put another unit in the kitchen, will that work ok? The kitchen opens to the foyer, the hallway and there's two pocket doors that separate the kitchen from the dining room. The three season porch can has two french doors leading to it and it is all sliding glass doors on the outside "walls".

Should I go with a central air system downstairs and two mini-splits upstairs?

Would a system with all mini-splits work on the rooms I would want cool work?

Or is there a better solution?

BTW, the first guy spec'n out the house measured room by room dimensions (including windows in each room). The second guy measured the inside dimensions of the entire house then measured the windows. Is there a right way and a wrong way or will they both work?

Thanks in advance for any help or suggestions or links to educate myself more...

[tinknocker service tech]

first guy wants room by room load calc witch is the better way
talk to him about the possiblity of running some supplys up to second floor through closet or other type access to the floor

HV woud be best way ssmall outlet and pipes are 3 inches

[skibme]

get another contractor or ten more. these guys sound like amateurs. there is a contractor willing and able to do the work, you just have to find him.mini splits have their uses but i wouldn't put one in your house.any house can be done.you may have to open up some holes to fish ducts around but it depends how bad you want air conditioning.get ready to pay . i used to do jobs like yoursand charge heavily for it.other a.c. contractors recomened me for the impossible houses. good luck.

[Sharp Snips]

Although this is my first post here, I have been perusing through these threads for a good amount of time. I am writing said first post because you mentioned a Unico and mini-split system, which I install all the time.
You also mentioned that cost was a factor and I can tell you for certain, unless you are using a junk contractor, that you will pay dearly for a high velocity system, which wouldn't fit your budget. We install Fujitsu all the time but I have been told that LG makes a similar system for a better price. However, mini-splits do have the word mini associated with them, so, take that for what it is worth.
Unico's are the way to go in my book, a major pain to install sometimes, but if you have the money and willingness to have a few holes cut and chases put in some closet space...it is instant equity and awesome comfort.

[markwolf]

get another contractor or ten more. these guys sound like amateurs. there is a contractor willing and able to do the work, you just have to find him.mini splits have their uses but i wouldn't put one in your house.any house can be done.you may have to open up some holes to fish ducts around but it depends how bad you want air conditioning.get ready to pay . i used to do jobs like yoursand charge heavily for it.other a.c. contractors recomened me for the impossible houses. good luck.

I agree.
There are guys that would toss a few mini's in to make a quick buck,then there are guys that don't mind taking harder jobs that take more time.

Where are you located?

[markwolf]

Reason I ask is there are alot of guys here there may be someone local to you that can help.

[gdtrfb]

We live on the north shore of Boston. I have two more pro's coming out to spec it out today. All of the names I've contacted I got via either Unico or Spacepak's list of authorized professionals. Investigating the companies before I contacted them, I wanted to make sure they do traditional AC too. I was not familiar with the mini-split concept until after those two gentlemen suggested that was the do-able option for upstairs.

Since that recommendation, I have been investigating that technology, where I came across this website. Like I said in my first post, this is the first home I have purchased. We moved in April and have been dealing with other issues. I am a total novice to hvac. I am not planning on doing any of the work myself, just looking for what will and will not work for my situation. I know I have to trust whoever I go with. I just want to make sure I make an educated decision. I don't have a problem interviewing several companies, I'm just afraid I find someone who will tell me what I want to hear but unable to deliver it...

[skibme]

go hi velocity, put the air handler in the basement, put all floor outlets on the fist floor. send one seven inch diameter pipe upstairs thru a closet to fed the second floor. you may have to run the flex between the floors to feed rear areas of the house( depening where the closet lines up.) the whole problem with capes is pulling the heat from the second floor. i used to goin the stairwell, then into the front kneewalls.don't be cheap or else you'll be sorry. post some pictures of your house.

[gdtrfb]

Will post pictures when I get the chance to take them. Had two more people come by and check it out. They discovered another challenge, probably better to elaborate with pictures, will take some and attach later.

But I will try to explain. The original cape has sufficient crawl space in the front knee walls to run duct. Will have to build window seat for window dormer to hide duct - not a problem. But the addition that has the foyer and two car garage on bottom floor with laundry room and large family room is presenting another challenge. The roof line over the laundry room matches the cape roofline. Also in the front, there is a skylight illuminating the foyer where the space of the kneewall would've been. Both guys said that would be problematic to go from the kneewall of the original structure into the laundry room and then to the room over garage. We looked at going through the backhall closet on the first floor up to the laundry room as an option to get to the laundry room and family room. There's really no way to go from the 1st floor front of the house to the 2nd floor kneewall without an exposed duct through either the living room or dining room...

Both of guys from yesterday are going to run the numbers and get back to me.

Will take pictures and post them with measurements over the holiday weekend.

Thanks for the info and have a great Independence Day weekend and to our friends up north have a good end to your holiday week...