Investor 路 Portland, OR 路 Member since 2021 路 32 posts 路 9 votes
Hello, I'm trying to price out a potential property that does not have central AC. There is no crawlspace or basement. It does have a pitched roof, but I didn't look up in there during the walk through unfortunately.
If I had to guess, roof looks like its about 30 degree angle and I would guess about 4 feet of clearance (5 tops) in the tallest part of the attic space. Is that sufficient for a central AC system? Anyone have any experience installing central AC into a similar circumstance I'd love to hear about your experience.
I've considered zonal, but it would also have to be tucked away in the ceiling, as this will be an AirBnB and the rest of the house has a historic vibe, so a big modern zonal unit on the wall is a no go.
I haven't used them much, but in general I prefer the central AC experience to zonal and some people say the zonal units also don't cool as well when it gets very hot outside? (like it is right now!) Has that felt true by anyones experience?
That's reassuring. Did a google search to understand what 3:12 looks like and after looking at the angle examples, I think it's a good bit higher than that even. Comparing the photo, it looks like about 6:12 actually. Obviously I understand they'll need to put eyes on it to confirm, but if they can put one in a house at 3:12, I'm feeling much more confident about it going in here.
Real Estate Agent 路 SD 路 Member since 2020 路 137 posts 路 65 votes
5y
1) there's a roof pitch gauge on the App Store that'll tell you your roof pitch quick and easy.
2) I'm assuming that by zonal you mean a mini split or ductless system. I had one at a previous home in Bend (about 3 hrs from you) I lived in and I loved it. AC room by room, and individual heat room by room. If the house were to be empty you can turn off living room heat but keep the kitchen heat going for the plumbing, for example. The compressor units for mini splits are awesome- quiet, power savvy, and small, you can tuck them in and hide the easily.
3) I'm not HVAC experienced, other than casual interest, but I've seen on This Old House the installation of smaller 4" ducts that run to a smaller room "port" that is circular, instead of a big vented rectangle.
Rental Property Investor 路 Concord, GA 路 Member since 2015 路 3k+ posts 路 3k+ votes
5y
Your best option is going to be to get an HVAC company out there to look over the situation. The air handler will need to fit up into the attic so the scuttle hole will need to be of a reasonable size. I just had a guy fit one into a hole in a closet ceiling that was 21"x20" It was a challenge. If it's a heat pump, you'll need adequate power to both the air handler and the outside condenser. So your load center (breaker box) needs to be considered as well.
Rental Property Investor 路 Member since 2019 路 6 posts 路 4 votes
5y
@Logan Loughmiller
As an HVAC contractor, I would suggest looking into the Mini Spit option mentioned by another poster. It could be more or equal cost but you wont have the ceiling leaks common with putting the airhandler in an attic space. easier to fix and also as mentioned can zone much easier. the technology has greatly improved in recent years. And these type situations where there was never duct work to begin with is exactly the problem they were meant to solve. best of luck and choose a contractor carefully.
Rental Property Investor 路 IL 路 Member since 2015 路 165 posts 路 107 votes
5y
A lot of good points mentioned here. Getting the HVAC unit into the ceiling space should be your primary concern. Like was already asked, is there a scuttle large enough to get a furnace and evaporator coil through? If so, you can have a horizontal system installed. A quick google image search will show you how it's designed to fit in a tight space like you're describing. Another mention about smaller ducts, there are "high velocity" systems that allow for insulated, flexible, round ducts as small as 2" diameter. This could also make the install easier in a tight space so the installer is not messing around with sheet metal.