Central AC and home investment

brewer12345

Give me a museum and I'll fill it. (Picasso) Give me a forum ...
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Mar 6, 2003
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I am sick of lugging wall ACs and to add insult to injury the 75# monster didn't even work when I installed it and plugged it in. What I am stuck on is how to cuff the decision on investing in the house vs. making do. The house is ca. 1950 and never had central air. We have 5 wall units and a heating oil furnace that sends steam to a radiator system (for most of the house, part has hot water base boards). I suspect that a central AC system would be a lot more efficient and it looks like I would be able to grab something like $2k in tax credits and utility incentives for something with the right efficiency ratings. OTOH we will likely be in the house another ~3 years and I do not want to overinvest in the house.

Any clue what these things cost installed? How should one think about investing in the house with such a short timeframe? Other thoughts?
 
The cost of retrofitting a house with central a/c depends on the architecture of the house: how many floors do you have, do you have an attic, a basement/crowlspace? In our case we have a 2 floor house with no basement, so some ducts had to run inside the house and bulkheads had to be built to conceal them. I think that this arrangement would be more expensive than if you can run the duct work in the basement for the first floor and in the attic for the second floor.

Personally, I think you should look at other houses in your neighborhood. If most have central A/C, then I think that installing a central A/C in your house will help its resale value. If not, you might be better off letting the future owners pay for the upgrade.
 
Central AC is pretty popular here, but it varies by 'hood/development. I would guess that something like 2/3 of the houses in my 'hood have it.

We have 2 stories, an unused attic and a basement in a house that is just under 2000 square feet. My guess is that they would have plenty of unobtrusive places to run pipes/ducts.
 
You're going to have to figure in the cost of fitting the mechanicals and the duct work and return air in your house. I just spent a little under $7K to replace the larger of my two units, but they just hooked it up to all the existing ducts, lines and return air. When I was getting estimates, one company insisted that I would need an ungodly sized furnace in order to match everything appropriately in order to qualify for the tax credit (he was wrong). He said he would have to hire a carpenter to come in and re-size the attic entry and beef up the supporting structure in the attic - it wasn't going to be cheap. You're probably going to have to get some estimates of the cost for installation.

Given that you're moving in 3-years (and I assume selling) it could be very difficult to recoup much of your cost. Mechanical system upgrades are hard to sell to as compared to something potential buyers can ooh and aah over, like a remodeled kitchen or bath.

You probably have to look at some comps and see how prevalent central AC is among the potential competition. Down here where the Summer is like what they get in the outer reaches of Hell, when you sell something without central AC you are definitely down in the lower range of real estate. My HOA bans window units because they detract from the appeal of the homes - but everybody has central AC here because the homes are less than 20-25 years old. But up north I hear it's different - although I still marvel at the thought of what the weather is like where they can get away with building a new house without central AC.
 
Yep, the layout of your house makes it a lot less expensive to install retrofit A/C than would be the case if they had to hide ductwork in closets, etc. There will still be some significant disruption for a week or so as they cut into the ceilings and floors to install registers, etc. You might also ask them to size the ducts for potential use in heating your home as well--when that boiler kicks the bucket, someone might be really happy to have the option to go with forced air heat/heat pump.

I've got no idea what this would likely cost, but I'd guess one major factor in determining whether it will be worth the expense is the price of the home. In an $80K house, it's less leikely that a $10K investment in A/C will pay off, but in $500K homes it's likely to be something prospective buyers are looking for .

Maybe an experienced real estate agent who has worked a lot in your neighborhood could tell you what central A/C is worth.
 
Just as a reference, a brand new 13-seer central heat pump system sized for a 2,500 sq. ft. home cost me about $5,600 2 years ago - installation included (but they just had to connect the new unit to the existing duct work).
 
Appreciate the comments. As we are further north than you guys, I suspect that we would get away with a smaller unit than would be the case in TX or AL. Jersey is humid and gets unpleasantly hot in the summer (which apparently starts May 1 these days, sheesh), but its not like the South.

Asking an RE agent is not a bad idea. I also think I will take a walk around the greater cul-de-sac and see what proportion of houses appear to have central AC.

My suspicion is that the economics will be something like spend $X after tax rebates/incentives, shave $Z off the electric bill annually and when we sell it adds $Y to the value of the house both in marketability and actual price received. I can get estimates fo $X, get a rough idea of Z, and Y is a SWAG.
 
You might not want to go this way... but it is an option... and since you are asking about a complete install, the costs might be cheaper...

Try a split system... they do not require ducts to be installed and each room can be programmed to the temp you want.... they are nice options that are big in Europe.. and I would think they would work for you...

One caveat.... I think the noise of the fans are higher than what I would want which you do not get with a central unit... I can not hear my unit at all... I only know it turns on when I feel the 'wind'....

I did not look at price when I grabbed these links... so if you go this way check out better priced ones...

KLIMAIRE Ductless Mini Split Air Conditioners heat pumps a/c deals online sales

ductless mini split air conditioner system mini split air conditioning ac unit -
 
I could not find it now.... but there also is a 'mini' duct system.... it does not use the large ducts that most systems use, but small 3 or 4 inch ducts... they have a lot higher airflow.... with a reto, this might be another good option...



BUT.... IMO, you will never recover the costs... you should only do this is you want to change how your A/C you space while you live there... is it worth it to you to get over the problem of lugging new AC units around... btw, how often do they go out:confused: I thought they lasted about 10 years or so... and in NJ might last longer since they are not used as much...
 
"Z" will probably be fairly small, if you use your window units like most folks (i.e. turn on the bedroom units only at night and in the rooms that are actually occupied, etc). Despite the higher efficiency of a modern central A/C unit, the increase in cooled area will probably just about make up the difference.

Three "pluses" for the central A/C unit (probably more significant if you planned to stay in the house "forever")
- If allergies are a problem in your family, installing a central air handler will let you add some filtration that may help (there's a lot of dispute on whether this filtration really helps, but some folks believe it does).
- When we lived in a three story house with hot water heat, there was quite a bit of stratification of the air temps during winter: uncomfortably hot in the top rooms, hard to get the lower levels warm enough. With a central air handler you can run the fan on low setting and it will do a lot to equalize temps across all the levels and in every room with a register.
- Basement moisture problems may be reduced in the summer with a central AC system. They do a good job of reducing moisture in the air, and by circulating the air in the basement and running it passed the AC condenser, it may help out. If you are running a dehumidifier in the basement now during the summer, you might not need to with central AC.

Ref the mini-duct systems Texas Proud cites: They are extremely popular in historic homes where it's virtually impossible to install standard ductwork. They are pricey.
 
In 2006 we had a heat pump and all the vent work installed in a 2/1, 1150 square foot house (built in 1944) for a little under $6,000.
 
I could not find it now.... but there also is a 'mini' duct system.... it does not use the large ducts that most systems use, but small 3 or 4 inch ducts... they have a lot higher airflow.... with a reto, this might be another good option...



BUT.... IMO, you will never recover the costs... you should only do this is you want to change how your A/C you space while you live there... is it worth it to you to get over the problem of lugging new AC units around... btw, how often do they go out:confused: I thought they lasted about 10 years or so... and in NJ might last longer since they are not used as much...

Yeah, I knew about the mini duct systems.

The smaller wall units last and last. I have a dinosaur from 1996 still in use which generally only gets fired up the 4 or 5 hottest days of the year. The big ones I have had terrible luck with. The last one died after 5 years and this one is on the fritz after 3 or 4 years.

Because DW is at home during the day, the downstairs is cooled all day, every day. Upstairs gets cranked up during the day at naptime for the kids and evenings for all of us. So I suspect we burn a fair amount of juice on AC. We also have extremely high power costs (like 20 cents per kwh), which magnifies my interest in efficiency I would imagine that the power savings would be something ike 300 to 500 a year. I am not expecting large dollar savings, and I do not expect to recover evrything. But if the game is something like put out 7k, save 300 a year for 3 years, and add 3 to 5k to the value of the house, it might be worth doing.

Allergies are also an issue for us.
 
My sister-in-law has a very old two-story house with radiator heat. A few years ago they put one central AC unit in the attic with ceiling vents to the second-floor rooms and a second unit in the basement with floor vents to the first floor, rather than running ductwork up to the second story. She is really cheap so it must have saved a lot of money to do it that way.
 
I'm working on getting a quote as well. Up here in NH its not that hot, but summers are usually very humid. I want the convenience of the central AC. My window unit is too noisy and keeps me up at night.

It will probably be too expensive, but I should get a quote this week. 1 floor, full unfinished basement under, 1400 sq ft ranch. Hoping it makes it easy...
 
Brewer, I would "tough it out" with window A/C units for three more summers and then sell the place. It's not worth the hassle of doing such a major upgrade for just 3 more years in the house, IMO.

Next time, get a house with central A/C since you now know that is pretty important to you.
 
On the other hand, when you go to sell your house, many buyers will not even see your house pop up in their search results if they put A/C in as one of their search requirements. People these days expect to be comfortable in their cars and homes, so A/C is getting to be expected.

I'd vote for having several contractors come out, assess your situation and give you quotes on what the job would cost.

I had a new A/C and furnace installed about 3 years ago (1800 sq. ft., 2-story house) and was amazed at how cheap the A/C (now) is. Running 24 hours a day in the summer (set at 74 degrees daytime and 68 at night), it only adds $1/day to my electric bill. I live in Michigan, so I think our summers are a lot like yours temperature and humidity-wise.

I also used to have to run a dehumidifier in the summer (which added a LOT to my electric bill). With the new A/C, I was able to get rid of the dehumidifier, too.

In terms of costs, as best as I can recall, I think running the new A/C is about the same or even less than what it used to cost just to run the dehumidifier.

omni
 
If you do decide to add central AC and or furnace make sure that you get a blower door test on your home to help properly size the unit. DON'T let them size your unit based on square footage. Some utilities will do this for free or a small fee. You could also just get an air source heat pump and kill two birds with one stone.
 
If you are fairly far north then you might want to consider a geothermal unit. It could replace your existing heat and save you money as well as qualifying you for the current tax credits. They are very efficient, quiet, clean, and have no outside equipment. They cost more than a standard heat pump, but the the efficiency is up depending on your location.

Just a thought as if you are putting in duct work anyway why maintain two separate systems, and why not look at the investment and savings opportunity-
 
Yeah, we will see what the contractors suggest when they show up tomorrow. I am open to their ideas, although there are limits on the capital I will put out on this.

As an aside, my weight training must be working out well. I spent a fair chunk of yesterday throwing air conditioners around (including several laden trips from basement to second floor) with units ranging from 40 to 80 pounds and I am not crippled or even sore today. Gotta find that silver lining...
 
Central AC is almost a must for resale, unless you live in hawaii or someplace like that. You might not recoup the cost, but you can enjoy the unit as long as you live there..........
 
Sizing on square feet is not the way to go. I had three bids on replacing my central air. All simply looked at square feet. I have vaulted ceilings which increase my cooled area. I went with a 4 ton unit rather than the 3 ton that was bid. It is often not enough on hot days in Texas. Sure glad I didn't listen to them.
 
I won't even look at a house w/o central air. Including when we were buying a house in MA.
 
The way to determine the size of AC needed is called a "Manual J" calculation (from an ASHRAE manual). Lots of HVAC folks use a rule of thumb based on square footage, and this is just plain lazy and can easily end up costing you money (or, if you buy too large of an AC unit, a less comfortable house. If the unit is too large it will not get your indoor humidity down to a comfortable range). If they insist that they can tell just by looking what size AC unit you need, you might want to find someone else.

The official program for doing this calculation costs a few bucks, but the one at this site worked well for me. It only takes a few minutes to enter the data.
 
First quote came in at about $8500, with no eligible tax credit. Expecting another quote tomorrow and another one early next week. Have not seen the details of the one we got. Will wait for more quotes before I really think about it, and want to make sure we are not heading for armageddon (don't think so).
 
Central AC is almost a must for resale, unless you live in hawaii or someplace like that. You might not recoup the cost, but you can enjoy the unit as long as you live there..........

Even in my old neighborhood, 90% of the homes have central a/c. Last fall when my gas furnace played out, I decided to add a/c as well. The window units got me by, but didn't really make me comfortable. So $4,000 later net of tax rebates, I have a new central heat and air system. I bought an American Standard Heritage 15 system. A heat pump with a gas furnace backup system. Does a good job too. Oh yes, my old duct work was good enough although they did have to add a little more insulation.

So I'm glad I bit the bullet. I don't plan to be here long term either, but I think the new system will help sell the house.
 
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