Thanks so much for the quick reply and I appreciate your expert opinion on this matter.

J.~

julie

Your problem is very typical of poor ductwork design for a 2 story home using a single HVAC system. Unfortunately, there is not a quick or inexpensive fix. I have two suggestions.

1. Contact an HVAC dealer and have him look at your ductwork and see if there are any reasonable suggestions for increasing air flow to 2nd floor.

2.Survey your attic insulation for improvement as well as look at removal/air flow exchange in attic.

IMO
Good LucK!

Hi Juile,
I have the same problem with my 2 story townhouse. The A/C works great downstairs, but it is always at least 4-5 degrees warmer upstairs. I think the solution would be to install a return air upstairs so that it can suck out the hot air upstairs and redeliver it through the A/C system. Otherwise if you have your return air downstairs, it is only circulating downstairs air that's already cold. I haven't yet got my return air installed upstairs, but I did do an experiment to test that theory with great results. I placed a fan (bigger than a typical oscillating room fan) on my second floor at my stairs and pointed the fan down the stairway. And I left the upstairs bedroom doors open. This way the hot upstairs air gets pushed downstairs and somewhat regulates the temperature throughout the house. I also set my thermostat to 1 degree higher (since it is now receiving some hot air upstairs, I don't want it to run more than it used to). Now my upstairs and downstairs temperature is off by only 1 degree in temperature. And I don't even have to set my A/C as low as I used to. I think you should give this a try... it won't cost you anythying at all... except the cost of a decent sized fan if you don't already have one. And if this works for you, then you can consider getting a return air installed upstairs.

Ya-all:

There is one thing about two story dwelling I see constantly passed over by many techs and homeowners alike.

!!!!!!!!!!HOT AIR RISES, COLD AIR SINKS!!!!!!!!!!

Any opening from the second floor to the first floor allows for the natural movement of air by temperature. Those of you with two story open great rooms being overlooked by balconies on the second floor are paying through the nose for style.

If better cooling is what you need for the second floor, controling the registers is not going to be the most efficient way unless you also close off the open spaces that allow the cold air to fall down and the warm air to rise.

I am not big on tall open spaces in a home as I figure I can always go outside, lay on the grass and enjoy the most magnificent open space that human beings can never duplicate. Put in decorative curtains that can open or close the "holes" (Stairs, balconies, etc.) from the second floor to the first and you will have better temperature control and lower costs.

Ruudman

It is a common problem do to the lack of balancing dampers in the ducts, wrong duct sizing, or both. Air takes the path of less resistance.

Your supply registers have dampers. The dampers are designed for fully open or fully closed. In order to balance properly you need balancing dampers in the ducts or a different style of damper on the register.

I don't have a/c in my place yet but plan to add it down the track, what does happen in winter from what I can gather (only moved in May) is that downstairs gets quite cold...

Downstairs windows are older, not low-e types like upstairs. Garage is attached, has insulated door but is obviously going to make that part of the house somewhat cooler....

Not too many registers and no returns downstairs....saw in Home Depot squirrel cage fan systems designed for installation inside ducts - I assume the idea is, to pull more warm (or cool) air out and spread it further...

I guess I need to learn more about balancing, dampers etc, but this system sounds as if it has merit too, since cold air does indeed sink, in winter I'll need to increase warm air flow downstairs to keep things even. Previous owners installed gas fp downstairs but I don't want to waste the gas when the house can probably be better heated, more consistently via the furnace.

Ceilings downstairs are finished so I have limited, difficult access to ductwork etc so I'll have to be creative finding ways to get in there.

I've been pondering how to deal with this in my new house; today was our first really hot day and we definitely have an upstairs/downstairs gradient.

One thing I find tempting (only half-seriously) is to run a duct from the basement to the second floor, and install a fan to just pump some nice cool basement air upstairs, and keep it circulating. It'd be a lot cheaper to run a fan to do that than the whole AC unit. I don't know how much it would help, but I'll bet it would help a little. Right now, all that cold basement air is just sitting there, wasted.

My returns are upstairs, so that is good. I've shut down most of my downstairs supply registers, and it does seem to help a bit.

I might be finding (still inconclusive) that temperature imbalance gets rather bad overnight, when the air conditioning doesn't run (because it's cooler out), and overnight the colder air settles to the first floor. At least with the AC running, there's some cold air being pumped upwards....

I had this same problem with my two story house. At night, especially, the downstairs would stay so cool that the AC wouldn't cycle on, and the upstairs would get progressively more and more stuffy until it was unbearable.

After many suggestions from HVAC contractors, including shutting most of the registers on the first floor, covering the air returns on the first floor, to force more of the hot upstairs air to be sucked into the system, neither of which worked very well, I found a decent solution.

First, it's helpful if you leave your AC fan running all the time, rather than just when the compressor is on. This keeps the air circulating around the house, instead of the cold air settling downstairs.

The biggest relief for the problem was when I had the HVAC guy separate the AC thermostat from the heating thermostat and move the AC one upstairs. After that, the problem mostly was solved. I had to keep most of the registers downstairs closed off, so it wouldn't get too cold, but I was able to compensate some by turning up the temp a couple of degrees.

Very True. all the posts are accurate, one mentions attic temp, and it is another cheap way to lower the temps on the top floor.
look at it this way, if the attic is sitting at 160*F or higher, then your cieling will be feeling that hot as well, and your heads (the part of your body that is closest to the cieling) will feel uncomfortable. radiant heat is pretty difficult to get rid of. a cheap way on older homes is to open up the soffet ventilation or add some if none is available. and close up the gable vents, while adding in a full ridge or a few power ventilators as high up as you can, spaced evenly apart. this will get relatively cool air flowing accross your attic insulation. lessening the radiant heat load on your heads.

closing off the staircases between floors will indeed make a huge differance as well.
John

Julie,

As the previous posts have said...it is what it is. Cold air falls, warm air rises. A 2-story or Cape Cod house should always have 2 seperate units for each floor.

Cheap fix? Yes. Buy the cheapie little 5K btu window a/c units from Home Depot or Lowes - they cost less than $100 each, and they have digital temp readouts, where you can set the air temperature. I use one for my bonus room, which is always hotter since it's above my garage. It works great, and even though it runs all day long when it's really hot, we don't even notice a difference in our electric bill.

Asthetically? Well, having a small window unit in each bedroom window is not the end of the world. And it's a lot cheaper than putting in a 2nd system for your 2nd floor.

Ruudman:

Good point on the two-story great room w/ balcony. We have a two-story cape cod with exactly that design. I have a very large ceiling fan in the great room that runs 24/7, 365 days a year. It is very effective in circulating the air.

And...here's the best thing. I have a pellet stove in the great room, so in the winter time, my heat pumps don't even come on unless the outside air temps fall below about 40 degrees! Talk about saving some money, that stove has saved me a ton.

Our electric bills were $235/month (every month) before I added the pellet stove. After I did a blower door test, energy sealed the house, and added a pellet stove, our monthly electric bill went to $135/month. And that $135/month even includes running a pool pump from April through September. It would be even less than that if it weren't for the pump.

neilw,

I tapped into my supplies and returns to add heat to my finished basement and originally I was thinking of shutting these off during the summer months because the basement stays cool.

Then I got to thinking that if I left these open, it would circulate the cool air from the basement to the rest of the house. An added benefit is that it keeps the basement air dry so I no longer have to run a dehumidifier in the basement.

I also have the problem during the summertime that it is hotter upstairs than on the main level. This is greatly improved if I close off all of the registers on the main floor and plenty of cool air makes its way down through the stairwell. With this configuration, temperatures are pretty close upstairs and down. Then I reverse this for winter months.

neilw said: One thing I find tempting (only half-seriously) is to run a duct from the basement to the second floor, and install a fan to just pump some nice cool basement air upstairs, and keep it circulating.

As I googled the same problem with the heat in my 2nd story bedroom, I happened across this post. Someone tell me - is there something wrong with this idea? I live in a 50+ year old cape cod. I've got a straight path from the basement through the back of a closet on the 1st floor to a wall on the 2nd floor. Couldn't I could conceivably run something up, with a fan (like a register booster fan - see http://www.improvementscatalog.com/product.asp?product=49254zz&dept%5Fid=10120) on the top? How large should the duct be? Do I need to use ducting material? I was wondering if something (more inexpensive maybe, and easier to work with) like the flexible hose used for my dryer's exhaust would work.

Thanks for any thoughts on my idea.

I've got the same problem, but my only cold air return is on the first floor in the same hallway as the thermostat. I have good crawlspace access behind the walls on the second floor so running a return duct from the upstairs rooms wouldn't be hard. Unfortunately there is no practical way to tie into the existing return duct since it it under the floor of my bedroom on the 2nd floor and there seems to be no way to get to it.
I could conect through the ceilings of one of the downstairs rooms but my choices are the kitchen, bathroom, utility room (where the furnace is) and a back bedroom used as a TV/computer room.
Does this sound workable? I would love to put it into the ceiling of the hallway just outside of the existing duct but the upstairs flooring is again in the way.

This is a bit long, but will give you some more ideas...

Let me suggest another place to look that solved an issue we had with our new home. It being ICF with foamed insulation and a metal roof, we thought we had planned for everything. But, we also realized that the back-half second story, which is open loft to the first floor 22ft below, & above the kitchen/living area at one end, with a room over the garage, would be somewhat warmer.

First, we re-balanced this Spring as we planned that unit to have fully dampered ducts when we built. That enabled the upstairs to stay at 79 when the bottom was at a comfortable 77 -- still not ideal. If we set the t-stat back to 76 and left the VS fan on low, then upstairs would stay at 77 and no worries. So, that worked when we had someone staying upstairs, or we used the media room above the garage. But, with the last 10 days of 100+ we had to set back to 75 to keep upstairs at 77 daytime for guests... again, not ideal.

BUT, here's what made the most difference this past Sunday after all the above...
There was a big return duct at the top of the stairs, in the loft on the wall, about 4 feet off the floor -- about 2.5 ft X 2.5 feet opening. Inside it was boxed off with sheetrock around/behind it (a half closet backs it on the other side) and two large return ducts empty downwards thru the box-floor to the furnace below it on the first floor.

Well, everything to do with the duct work was masticed really well to to the floor of the box -- no leaks. But the sheetrock inside and the 2x4 frame of the box were not taped or sealed at all. So, the return was sucking air from within the wall spaces above, below and behind as well as from the conditioned space.

I got some DAP sealing foam (the white, washable kind) and some silicon caulk. I sealed up every sheetrock joint and I sprayed foam into every nook and cranny along the 2x4 studs. I then duct-taped wherever any stud met sheetrock. The A/C was on low while I was doing this over about an hour. By the end of the hour, I could noticably feel more air moving around me and down into the ductwork.

It completely solved our issues and now I can keep it 77 downstairs, leave the fan on low, and it's 77 upstairs and much more even temps all over because the air is actually getting pulled around now. AND, the humidity level has dropped 2 points (from 46 to 44%) from its averages before this too.

So, look for every return you have and see if it or the boots it has need better sealing from the walls around it.

Well, I am glad that I am not the only one suffering. I own a two-story brick house in Nashville and I have the same problem. I too have found that by leaving the thermostat fan to continuously run instead of the auto mode that it is making a big difference. I have not received my first electric bill since making this change so I am kind of nervous about it running all of the time. Can anyone tell me if they do this and how much the difference cost them? Any information would be great!
Thanks!!
Joey

I have the same problem with air return on first floor.
The second story is only a stairway up to a bonus room.
The windows are small horizontal sliders so cant install exhaust fans. The ceiling is cathedral so no room to put in a 2nd story air return.
I figured since warm air gous up and cold air stays down, then run a small fan at base of stairs pointed straight up to help mix up the air throughout the day. I also installed a whole house fan - not able to fit the big ones without a roof truss engineered modification ($$$)so went with a quiet cool type that puts the fan mechanism in the attic so it runs quited (love it!) - this is effective at end of day to exhaust hotter upstairs air and replace with either 1st floor air (by opening a downstairs window or just running AC) or opening a 2nd floor window to cool that area seperately without cooling downstairs air when not desired. Final note to 2 story owners: when at night the 2nd story air "cools" it will flow downstairs and actually "warm up" the downstairs iar that is relatively cooler. This is a frustrating phenonomenon that the whole house fan almost eliminates.

Running your fan continuously should not make a big difference in your electric bill, its is hard to calculate exactly, due to the differnce in rates and all. Just do as you are doing and compare bills after a month or two.
I would surely NOT run an attic fan and your a/c at the same time!! You are surely wasting energy by doing that.

I am glad I am not alone. It was hot this weekend and with the air running pretty much all the time the second and first floors were more stable. I did turn the fan to on as well. The problem indeed arises at night when the temp difference between the two floors vcan be as much as 7 degress which means you either freeze on the first floor or sweat on the second. Also, having the fan set to on at this time make sthe house feel stale. Also, the house starts to feel clamy upstairs at this time...sticky.

Perhaps a programable thermostat will solve the problem to a degree...maybe moving the cooling thermostat upstairs.

It is almost never a good ideal to close vents in a room. Closing vents will not damage the ducts, but it certainly can cause the system to shut down and damage the HVAC equipment.

There should be no more than a 2 degree or 3 degree difference in temperature in any room. It is required of those in the business that do installations.

What I suggest is, call at least two heating and air conditioning contractors and tell them you are having an air flow and air temperature problem with your two-story house. Ask how much would they charge to do an analysis of your situation.

PLEASE do not expect to get this service for free. It can be time consuming for the contractor. Your situation is solveable. And, it might not be an HVAC problem.

Phillip

Fairyprincess must be living in fairyland. I was in 4 two story homes this holiday weekend. Three had no more than a 3 degree temp difference between the first and second floor. One was more like mine, a little to hot upstairs; for me anyway, but rather cool downstairs. None had the stairways closed off either. In fact, most new homes built today are open concept homes. Should all these folks expect to have a hot second floor. I think not!

Yes hot air rises, cold air sinks...so what. Some homes are just inaquately built to account for this. Those of us living with this inadquacy simply are looking for methods to overcome it...which IS possible.

You give up to easy!

Yall done went and made the old man mad.We had him calmed down too.

Am I correct in assume that all of you with 2nd floor cooling problems blow the air up from the basement where the coil is stacked over the furnace? Do any of you have a blower & coil in the attic w/ ceiling supply vents in all the rooms? I am about to pay $5k more than a stacked basement system for an attic-based system with ceiling vents just for cool air in every room. The thermostat will go in the second floor hallway. There will also be a single return grid in the ceiling of the second floor hallway for the whole house. My HVAC contractor assures me that this will chill the whole house (except basement) evenly in the summer. Your thoughts?

Yes, in our current home. In our old home we had the unit installed in the attice and blew the ac down...it was an ac only unit there...not a heat pump. It worked wuite well....cool everywhere.

Once the downstairs is cooled, there is little heat to rise to the second floor except that heat which infiltrates and is gained thru the walls at the stair on up. This natural flow goes up. Even with a system upstairs cooling the space, the cooler air will travel downward and exchange with the warmer air going up. Yes, if the upstairs and downstairs were isolated in their own inviroment- all would be well, but that's not the way homes are.
I think the tornado idea was a good one.

Just got the proposal to install the attic-based AC system I described above. The contractor guarantees for 5 years that inside of house will be 75 degrees on a 95 degree day with no more than 3 degree difference from thermostat temp in any room, upstairs or down. I am sure that I am getting gouged b/c I live in a high-rent suburb of NYC, but I got four estimates all in the same price range. For my 2-story colonial, I am getting new 70k/80 AFUE Carrier Infinity furnace, 5 new heat vents, 1 new heat return and some heat duct relocation work due to the removal and addition of several partition walls, whole-house humidifier and Aprilaire filter and a 2.5 ton 15 SEER Carrier Performance AC with coil and blower in suspended in attic and all new in-wall AC ducts and ceiling vents to eight rooms and two thermostats for about $18,500.

Based on this forum, I figure I am probably being charged double the national average, but I'm already in bed with this contractor for half the install, so I'm doing it and not looking back.

That does it!!!!!!!!!!!

Enough mister nice guy!!!!!!!!

I'm moving to New York!!!!!!!!!!

Fairyprincess

$18.5K - holy sh%t.

Only can get the house to 75 on a 95 degree day? At least when its that hot outside my 20 year old trane can get me to 70 - 72...and so long as the unit is running more or less regularly, the temp difference between the floor is reduced from 8 degrees at night to 3 or so.

We are about to retrofit our 3-story Victorian home with central air. We have a forced hot air system with a single return on the first floor.

We've talked to 3 different HVAC contractors, and their advice differs. One proposal has us attaching a compressor (5 ton Carrier 15 SEER) to our existing heating system and zoning the ductwork into 3 zones. This is the one we were about to go with. But now we are concerned that this will not be effective for the upper floors (particularly the 3rd floor), especially because there is no return for the hot air up there.

Will zoning the 3 floors separately help the too cold/too warm problem, or is zoning futile against the laws of hot and cold air? Is it pointless to try to blow cold air into the upper floors without returns up there?

Zoning is the answer to the problem with upper floors being warmer than lower floors. It gives you the ability to control the temp in each zone in heating or cooling. It is expensive to retrofit if it can be done, but well worth the cost. It takes care of the too hot/too cold problems with multi story homes. We install zoning in aprox 95% of the jobs we do, we have no complaints or call backs for this type of issue because of it.

Rheemman:

If you haven't had any complaints, it's because your customers are wusses, wimps, and too scared to complain.

If you have open spaces allowing cold air to fall to the lower floors, you CAN NOT------EVER------control temperature AS ACCURATELY--------OR AS CLOSELY as when the floors are closed off from each other-------PERIOD-------END OF DISCUSSION--------CAN'T FIGHT PHYSICS!!!!!!!!!!!

Based on archives records, you either ARE NOT the poster who used to call himself RUDDMAN or you are and you have really wimped out.

Fairyprincess

if there are 3 zones and three thermostats then yes hot air rises and maybe the upper floor units will run more but I would think to the person living there they would not notice a difference between floors if all thermostats were set to say 72 degrees....?

Okay, I'm another "too hot up, too cold down" with my 1970's split level. The bedrooms are unbearable in summer. [This is especially a problem when a girl reaches a certain age and her personal thermostat becomes permanently: "too hot all over".] This summer I had decided to give up and switch to sleeping in the family room.

Reading all this discussion makes me crazy. So Fairyprincess, all I need to do is find a way to close off the stairway from my living room up to the bedroom area (has side walls, but no doorway at the bottom and no raised ceiling) to get my upstairs' rooms cooler?

Not sure how I would accomplish this efficiently and safely since the bottom steps extend past the wall framing. It would be the cheapest overall method to try first, I guess. I wonder if this would also keep it warmer downstairs in winter? I will do some Googling and see what's available in folding doors.

Too bad we didn't consider an attic A/C when we bought our new one several years ago.
Liz

Elizabeth5:

A properly designed system does the best it can but just like adding water to a barrel that has a hole in it, the cold air is going to flow down and out.

If you can employ curtains that go down to the floor in the open spaces leading downstairs, that would be one cheap way to stem the cold air flow.

If your primary needs are one or two rooms, buy a $90.00 5,000 btu window mount system and close that room when you want to keep the cold air where you need it.

Once you set the thermostat on the window mount unit, it will only come on when the central unit is not keeping that particular room cold.

An old friend of mine, who used to sign in by the handle of Ruddman, saved an elderly lady in Florida over $9,000.00 dollars by telling her to forget about a $10,000.00 central air installation and to buy less than $1,000.00 dollars worth of window cooling units and use them according to need for the areas she wanted to cool. Naturally she kept them all on to cut down on humidity, but she didn't have to have them all on or super cold to do that and on those days or nights where she wanted colder temperatures, she just turned the thermostat on that particular unit in that room lower.

Good luck!

Fairyprincess

Yes, cold air sinks and hot air rises, but shouldn't a good A/C contractor be able to account for this, or even take advantage of this passive air? I'm no A/C expert--quite the opposite--but it seems to me that blowing out cold air primarily on the upper floor and letting it sink, rather than having lots of ductwork blowing cold air to the first floor, would go a long way towards solving this problem.

Johnieb:

The same ducts are typically used for heating as well as a/c. If more ductwork is designed for the upper floors for summertime a/c, the upper floors will roast in the winter.

We remedy this problem in around 350 houses each year. Its not difficult or expensive. It is not dampers or additional equipment or booster fans. If you would like some advice, email me at eaglecrestmechanical@msn.com or call me (303)451-5607 I can probably help you with this problem. I'm not big on these streams or blogs or whatever this is. Just stumbled upon this. I may not return to this to see your messages but would be glad to talk with you.

I live in house where my roommates and I rent the top 2 floors of a 3 story ~1910 Victorian. The 3rd story is a bit or a converted attic / servant's quarters. There is still a higher attic over part of the house. There are separate HVAC systems for the first and basement and the 2nd and 3rd. We get the benefit of the renter below heat and they get our AC. The 3rd floor bakes in the summer and bakes in the winter. I have completely closed all the vents on the 3rd floor (during winter) because the heater warms the 3rd floor excessively while the 2nd is still cold mostly thanks to drafty windows which we cover in plastic. Also the furnace is on the 3rd floor center and the thermostat is in the center of the house but right next to the open stairwell. The air return is in the ceiling of the 2nd floor right hall above the thermostat and right next to the open stairwell as well. The 3rd floor where I sleep is too hot (in winter).
So I was wondering has anyone had luck with hanging a curtain to block the stairwell and to keep the downstairs heat down. Is this worth the trouble? What type of curtain should I use to be most effective? Clear plastic strips? Cloth? How about esthetics? Any suggestions on what might look - well - not that bad?

Also, I was thinking that the air return would be better (for heating anyway) if it was closer to the floor to suck up cold air rather than hot. Would it be wise/worth it to extend this from the 2nd floor ceiling to the floor? I could take off the grate and put in a make shift duct for winter. It would look aweful but if it will save me a couple hundred on heating I would go for it.

BTW our gas costs $1.30620/Ccf and our winter bills are $300-$350/month. And the 2nd floor is about 1300 sq. ft. and the 3rd is about 950 sq. ft. Too much info? :)

Hi , I am a houseowner with a problem . I have a lounge that has a high vaulted ceiling , with a staircase that runs up open plan to the mezzine level which accesses the upper floor bedrooms. My problem is that I have the usual problem of it being very hot up on the mezzine level whilst very cold at the lounge floor level primarily in winter. I have an idea that It could possibly be improved by fitting a few ducts with pipes that has quiet fans that could suck the hot air from the upper level and circulate it back at ground level . It would mean pipes in the wall . Kind or heat circulation system. Is there anyone out there that may have experience in this field that might give their opinion based on knowledge of wether this may work to raise the temperature at floor level to give significant benefit of comfort. Thankyou to anyone who give me replies or advice.

Wow. Some of this I read is amazing. You guys that guessed hot air rises are correct. Good job. Now the true problem starts with people believing they are cooling a house. In reality you are drawing heat out the air. In return you get a cool house. When heat rises and there are no returns on the second floor, it is going to be hot. This problem started with the home builders and their ways of saving themselves money on a job. Any two story dwelling should have two seperate units or one high dollar zoning system. That way each floor is satisfied with its air temperature. So, if you have one of these two story homes with one unit I suggest installing a second return on the second floor. This will aid in recovering that hot air and replenish with cold air. Sorry some of you have to weed through the ridiculous to get to the pros.

Most of the things said are true to a point, the truth is, especially with older houses heat rises, period. So upstairs is an oven and downstairs is an ice box when you try to regulate it. Putting in the return air from upstairs is great, but expensie. The easiest and most cost effect solution is to put an exhaust fan in the floor upstairs straight down into the room that has the return air and have it kick on by thermostat of it's own. You can do this for a couple hundred bucks yourself and problem is solved. Hot air is blown back down into the lower floor. and heats up the downstairs aand is pulled into the return to furnace/hvac. This solution also operates the opposite way when it's summer and you want cold air throughout the house........

Nearly 13 years after this post appeared, it's safe to assume the problem has been resolved, they've decided to live with it, or have moved out.