Recycling dryer heat

[ChadTower]

So, the cost of heating my house this winter is ticking me off.  Thanks to high prices, we've already spent as much on oil this winter as we did all of last winter.  I'm trying to find ways to conserve heat.

My wife runs the drier for like 3 hours a day.  As most driers do, it vents to the outside.  That's a lot of hot air.  Has anyone tried to vent it to the INSIDE?  I bet that would warm up the basement a few degrees.

[JackTucky]

It's VERY Humid air.  You have to get rid of that humidity.

JAckTucky

[ChadTower]

There is a dehumidifer down there that only rarely kicks on during the winter. 

[menace]

prolonged use of moist air will damage the insides of your wallsamong other things --if your humidifier can keep up with a dryer running 3 hrs a day it would have to be a very large industrial model to pull that much moisture from the air in such a short amount of time.  I agree its a terrible waste of heat but I would recommend finding other solutions.

[JackTucky]

prolonged use of moist air will damage the insides of your wallsamong other things --if your humidifier can keep up with a dryer running 3 hrs a day it would have to be a very large industrial model to pull that much moisture from the air in such a short amount of time.  I agree its a terrible waste of heat but I would recommend finding other solutions.

I'm no expert, but menace sounds like he is.  What he said.

JackTucky

[ChadTower]

Hrm... my pins are in there, don't want to worry about more humidity than is necessary.  

[Stingray]

Hrm... my pins are in there, don't want to worry about more humidity than is necessary. 

This alone is a good enough reason to keep it vented to the outside, IMO.

-S

[JackTucky]

why don't you cool the air, the water will condense, get rid of the water, then heat it up again, then put it in the basement.

problem solved

JackTucky


 

[menace]

I just got thinking--you are an avid freecycler--get some spare dehumidiiers--remove the coils and align them in series in a closed fixture--dryer air would pass inside, pass over the dehumidifier coils and you could recover the air sans liquid--course i have no idea if it would work since the act of dehumidifying cools the air but if you're bored on a sunday it might be an interesting experiment--who knows you could make it into a million dollar idea (i get 10% if you do)

[mmmPeanutButter]

Just get an air-to-air heat exchanger and a small fan.  The air streams (inside and dryer) would never mix.

[thebrownshow]

Tell her to stop doing lanudry so much and just febreeze your pants.

[Stingray]

Tell her to stop doing lanudry so much and just febreeze your pants.

Or take it a step further and go with the patented MissionControl "I don't wear pants" philosophy.

-S

[ChadTower]

Just get an air-to-air heat exchanger and a small fan.  The air streams (inside and dryer) would never mix.

What is an air to air heat exchanger?

[Havok]

Check out Home Depot - I thought I saw something there once that attached to the dryer outlet for heating inside. It didn't exactly vent the air to the inside, was some kind of heat exchanger. Can't remember for sure, but I think it was HD...

[mmmPeanutButter]

Just get an air-to-air heat exchanger and a small fan.  The air streams (inside and dryer) would never mix.

What is an air to air heat exchanger?

Like this kinda.  There are different types.

[I've seen them a lot simpler than this one in the pic)

I've seen one that they made specifically for getting more heat from the chimny on a wood burning stove.  I'm sure you could use the same on your dryer.  Just wire it up so it turns on when your dryer is on.

[ChadTower]

Check out Home Depot - I thought I saw something there once that attached to the dryer outlet for heating inside. It didn't exactly vent the air to the inside, was some kind of heat exchanger. Can't remember for sure, but I think it was HD...

Sounds a lot like what mmmPeanutButter is describing.

I just referred to someone as mmmPeanutButter.  WTF.

[mmmPeanutButter]

I just referred to someone as mmmPeanutButter.  WTF.

It's better that mmmCockandBalls   

[More Cowbell]

Put on a sweater.

[shmokes]

You should just talk politics at home more often...   

[ChadTower]

Put on a sweater.

Already been doing that... we've been keeping the thermostat on like 65.  It's the stupid oil prices, too damn high.

[JackTucky]

Oil heats a dinasour!  Oil heats a dinosaur!

That damn radio commercial from about 5 years ago....

jacktucky

[More Cowbell]

Put on 2 sweaters. 

Seriously, I'm with ya (although natural gas, not oil). Our issue is that our daughter's room is on the far end of the house from the furnace/AC so it's the hottest room in the summer and coldest in the winter. We put a little space heater in there but I worry about the safety of it and it uses lots of electricity. I think I'll put 2 sweaters on her.

[Stingray]

I've seen one that they made specifically for getting more heat from the chimny on a wood burning stove.  I'm sure you could use the same on your dryer.  Just wire it up so it turns on when your dryer is on.

I've seen those, but would never have thought of using one on a dryer vent. That's actually very clever.

The lint won't clog it up will it... or am I misunderstanding something?

-S

[mmmPeanutButter]

I've seen one that they made specifically for getting more heat from the chimny on a wood burning stove.  I'm sure you could use the same on your dryer.  Just wire it up so it turns on when your dryer is on.

I've seen those, but would never have thought of using one on a dryer vent. That's actually very clever.

The lint won't clog it up will it... or am I misunderstanding something?

-S

It might with the kind in the drawing I posted cause the channels are very small.  But the one for chimneys is different.  I don't know why I cant find a pic of google.

There is a tradeoff.  The smaller the channels, the greater the heat recovery, but the higher chance of plugging it up.  Larger channels, no plugging but less heat.

Google has forsaken me!

[mrhowell]

Sorry your energy costs are so high.  I guess i'm lucky living in the south.  My electric bill averages about $130.00 a month.  No oil or gas thank god.  Thermostat on 76 in the winter and 68 in the summer.  Now my Chevron bill is $380.00 amonth ( my wife drives a lot for her job).  Have you looked in to under floor radiant heating?  That is if you're planning on staying the house for awhile.

[mmmPeanutButter]

or just get a solar air heating system.

http://www.solarunlimited.net/solarwall.html


(I'm not completely impartial)   

[nostrebor]

The chimney heat exchanger is called a magic heat.

You could also try sex. It generates a lot of free heat and requires less mechanical skill than installing a magic heat. If the basements is cold, just relocate the sex to there.

Simple!

[ChadTower]

I'm married.  The sex is already cold enough.

[mmmPeanutButter]

The fireplace one is called a magic heat.

I am impressed!  you found it.

[thebrownshow]

Thermostat on 76 in the winter and 68 in the summer.

Even if you reverse those (76 in summer and 68 in winter) you don't even come close to what I set my thermostat at... damn.

[nostrebor]

I'm married.  The sex is already cold enough.

Perhaps it has something to do with the mechanical skills involved?

[ChadTower]

It's the bureaucracy involved.

[nostrebor]

Well... didn't mean to bring up politics.

Just call me a troll and get back on topic then.

[menace]

keep in mind that you need somewhere for all that condensate to go--all those heat exchanagers are designed for dry heat--something that is supersaturated like dryer air will drop ALOT of moisture as the heat is drawn out and transferred to the colder air on the other side of the exchanger plates/coils whatever.  Also you'd need a filtering device of some kind as alot of dryer lint makes it past your dryer's filter and out of the house.

  I think its a workable idea though, anything to help reduce our energy demands is a good thing in my eyes--when gas and oil guys are behind me in line at mcdonalds, then i will have reached my conservation goals-----daisies---!

[Stingray]

Okay, so let me ask this. Suppose you were to install the heat exchanger inside the house between the dryer and the wall, inline in the vent. Would that setup keep the heat in the house and still blow the moisture and lint out the vent?

-S

[mmmPeanutButter]

maybe mount something like the Magic Heat sideways and put a small drain on it?  I think maybe as you're pushing the cooler air through the tubes, condensate might form on them.  You wouldn't want this to drip back down the dryer.

I have no idea what I'm saying.   

[ChadTower]

Maybe I'll just disable the door switch so that she can run the dryer with the door open.

[ArcadeMaze]

We did that for a little bit, but then stopped because I am under the impression that dryers give off Carbon Monoxide.  Well, on Gas Dryers anyway since there is a gas flame involved.

Well, I could be wrong, but that's what the guy that did a carbon monoxide test on our house told us.

[Kremmit]

I thought about doing a dryer heat thing here.  I was going to adapt the design from a counterflow wort chiller (that's a homebrew beer thing).  Have a look at the "Fermentap Convoluted Copper Counterflow Chiller" on this page:
http://www.undergrounddigital.com/brewinghardware.html

Basically, it's a smaller diameter pipe inside a larger diameter one.  For beer, you run the hot wort through the inner pipe, and hook the outer one up to the cold water tap.  You run the flows in opposite directions, and by the time the wort gets to the far end, it's as cold as your cold water, if the chiller is long enough.

You could rig the same thing up with air lines, and maintain the large diameter vent pipe, so you don't have lint clog problems.  It wouldn't need to be a giant coil, you could shape it however fits your basement the best.  Just rig a fan to the outter pipe, and feed the outflow into the area you want to heat.

[ErikRuud]

Chad,

Do you have forced air heating?  You will get a lot more benefit from this http://www.aeroseal.com/ than you would from trying to squeeze a few more BTU's out of your dryer.

I had it done at my house last week.  The testing showed that my ducts were leaking 241 cubic feat per minute.  After the sealing process, the leakage is down to 50cfm.  They can't go lower than about 50cfm because the back pressure starts to build up and the sealant will get blown back into the blower.

Before and after airflow test at each register showed a 30 to 60% percent increase.

The improvement was noticable right away.  The second floor was always colder than the first, now it gets just as much heat at the first floor.

The cost was 1,250.00.  Between a credit on our gas bill and the projected 40% reduction in heating costs, it should pay for itself in two years.  That does not take in account the improved cooling efficiency which should reduce my electric bills in the summer.

[ChadTower]

I do have forced hot air... I'll look into the concept.  Thanks.  I do not have central air, though, nor do I have gas so I wouldn't get a credit.

[ErikRuud]

I don't know if all gas companies give the credit.  Aeroseal in my area is handled through our local gas utility (NICOR).

[ChadTower]

There isn't an Aeroseal office within hundreds of miles of my house anyway.  Looks like most of them are in places like California and Arizona and Florida, places where heat is not much of a concern.

My system gets used for heat from November to April, and for heat only, so it looks like three strikes against the service.

[mr.Curmudgeon]

Didn't dig all the way through this thread, but three things I've done in order to save on heating bills are:

1) Turned down my hot water heater to the lowest acceptable setting. Ours was cranked. I wrapped it in custom fit insulation as well.
2) Lowered our thermostat and use electric space heaters (with safety cut-offs if they tilt) for the rooms I'm sitting in.
3) Plastic window sealer/insulator

Our place is STILL freezing, but it's better than paying crazy gas bills. So far, we've managed to keep the cost roughly the same as last year.



mrC

[mr.Curmudgeon]

Another really stupid-simple thing to do, for added efficiency - especially since she does a bazillion loads of laundry - is to take out the dryer filter and clean it. Those dryer sheets leave a film on the filter which causes the dryer to work 2-3 times as hard.

"Take your filter to the sink. Run water through the screen. If it holds water, it has a coating left on from your dryer sheets. Take an old toothbrush and wash it with hot soapy water to remove the residue. Rinse throughly."

More from Snopes: http://www.snopes.com/inboxer/household/dryer.asp



mrC

[ChadTower]

1) Turned down my hot water heater to the lowest acceptable setting. Ours was cranked. I wrapped it in custom fit insulation as well.

Our water is REALLY COLD.  If we turn it down any lower than it is then the dishwasher becomes useless, and as it is, it's a lot less effective during the winter than it is during the summer.  As for the blanket, two different HVAC repair guys have told me that blanket wrapping your heater may save some energy but it substantially reduces the life of your water heater.  Something about certain parts of it actually being designed to vent excess heat and if it is unable than it breaks down faster.

2) Lowered our thermostat and use electric space heaters (with safety cut-offs if they tilt) for the rooms I'm sitting in.

Does this really save cost or just transfer it from the oil to the electric?

3) Plastic window sealer/insulator

This I've done on a few windows, but ours are vinyl, double paned, and pretty good.  We lose less through the windows than most people, I would suspect.

Our place is STILL freezing, but it's better than paying crazy gas bills. So far, we've managed to keep the cost roughly the same as last year.

Sadly, the jumps in gas cost are probably going to be in line with the oil jumps soon, and then even this stuff won't work anymore.


And yep, done the dryer thing, I do it about every other month.

[mr.Curmudgeon]

Does this really save cost or just transfer it from the oil to the electric?

It transfers some, but it negligible. I suspect that since you've got a larger family, it may not really work as well though.


mrC

[ChadTower]

I don't think it would either.  We're all spread out through the house for much of the day.

I think my next step is probably to replace the thermostat with a digital programmable.  That way I can put it to 64 during the times people aren't around much, up to 68 when we're home, and back down to like 65 when we're asleep.

[mr.Curmudgeon]

Oh, another thing...I have no idea if this'd be a concern or not, but it's worth exploring.

Isn't there a danger of carbon monoxide poisoning if you bring the dryer air into the house? I remember something about our landlord being fined because our downstairs dryer wasn't vented to the outside properly, and the dude said something about health issues.

Again, I'm not sure...but that would suck.


mrC

[Luxury]

If she's doing that much laundry, then just take those fresh clothes out of the dryer and put them on yourself!  That will heat you up for about 15 min right there.  If you time it right with each load, you could have perpetual warm clothes.

The oven also works for this method.

[JackTucky]

Isn't there a danger of carbon monoxide poisoning if you bring the dryer air into the house?
mrC

Yeah, this was brought up before and to me seems like the most important reason not to try this sort of thing.

Jack

[ChadTower]

It also may only be an issue with gas dryers, since there is nothing burning in an electric.

[farmecologist]

During the winter our basement seems to get colder when the dryer is running.   Since the dryer pulls in quite a bit of house air, and then expels it outside through the exhaust vent,  my logical thought was to try rigging up an outside air INTAKE.  In other words, try to get the dryer to be a 'closed system'.    I did a few google searches and came up with a couple interesting threads:

http://groups.google.com/group/alt.home.repair/browse_thread/thread/b46512c9abf88807/af6f4bf793cb0ff1?lnk=st&q=electric+clothes+dryer+outside+air+intake&rnum=2#af6f4bf793cb0ff1

 
http://groups.google.com/group/alt.energy.homepower/browse_thread/thread/25147c5eadffbe4b/00e322c3d505bb54?lnk=st&q=electric+clothes+dryer+outside+air+intake&rnum=3#00e322c3d505bb54


As usual, differeing opinions.  Interesting reading though!

[ChadTower]

Man, I would think that trying to pull 5 degree air rather than 55 degree air would burn up a LOT more energy.

[mmmPeanutButter]

During the winter our basement seems to get colder when the dryer is running.   Since the dryer pulls in quite a bit of house air, and then expels it outside through the exhaust vent,  my logical thought was to try rigging up an outside air INTAKE.  In other words, try to get the dryer to be a 'closed system'.    I did a few google searches and came up with a couple interesting threads:

http://groups.google.com/group/alt.home.repair/browse_thread/thread/b46512c9abf88807/af6f4bf793cb0ff1?lnk=st&q=electric+clothes+dryer+outside+air+intake&rnum=2#af6f4bf793cb0ff1

 
http://groups.google.com/group/alt.energy.homepower/browse_thread/thread/25147c5eadffbe4b/00e322c3d505bb54?lnk=st&q=electric+clothes+dryer+outside+air+intake&rnum=3#00e322c3d505bb54


As usual, differeing opinions.  Interesting reading though!

Can there be some kind of punishment for using such long links??     

[farmecologist]

Yes that point is made in the thread, and is certainly valid.   However, another point made was that the cold outside air is quite a bit LESS humid than the warm inside air..and therefore has quite a bit more drying capacity when warmed.   Who knows..

Another alternative mentioned is to get a condensing dryer that you can vent inside WITHOUT the problem of humidity.   However, I'm sure the condensing process uses energy too!

As with anything, there are no easy answers.    

Heck just buy a windmill and generate your power that way.   Yes, I have considered it..before I saw the price. 

[shmokes]

It would be extremely costly up front, but getting completely off the grid is pretty damned appealing to me.  And just think how happy you'll be after the next terrorist attack when you realize you're the only person who isn't dying of botulism or that you're the only one who still has power or heat.

Chad....go get a digital thermostat today.  I've been using one for about the last seven years and they're so ---smurfing--- great.  Mine drops the heat to 60 at 10:00pm, and cranks it back up to 73 at 6:30 a.m., but drops it down to 55 at 8:00 a.m., where it stays until it puts it back up to 73 at 4:30p.m. in anticipation of my wife's or my return home.  Weekends are programmed seperately from weekdays (and this thing is 7 years old....the new ones are probably much more customizable).  There are only two apartments in my building and they are almost identical in every way.  My next door neighbor's gas bill was about 60% higher than mine last month, even though my apartment is always perfectly comfortable when it matters.  I keep telling them that they'll have a ROI in one to two months if they just spring for a digital themostat.  Even without a ROI, they're just damned nice to use.  One of those little things that make life a little better.

[ChadTower]

Yeah, gotta do that.  I've been meaning to for a long time.

I wonder how one determines which are compatible with their heating system.

[mr.Curmudgeon]

And just think how happy you'll be after the next terrorist attack when you realize you're the only person who isn't dying of botulism or that you're the only one who still has power or heat.

Is that before, or after the rest of the dumb-assed, short-sighted neighboorhood comes to bash you over the head and take over your house?


mrC

[ChadTower]

The sad part is that he's right.

[Zakk]

How $$$ are we talking here?  I'm just curious, I don't know if we all compared bills yet.  For me it's $300/mo for gas and $250/mo on hydro.  That converts to about $520 per month USD.  I keep the house @ 72 deg or higher.  I've really been considering a new super-duper-high-efficiency furnace, or adding an adapter that runs your hot water pipes through some kind of heat exchanger in the furnace airstream (Is that what you were guys were linking to?).  Just don't know if what I'm paying is way out of whack. (?)

Oh, and I would NEVER vent a dryer into a house in the winter.  Mold problems really really really decrease house value.

[Ed_McCarron]

I don't think it would either.  We're all spread out through the house for much of the day.

I think my next step is probably to replace the thermostat with a digital programmable.  That way I can put it to 64 during the times people aren't around much, up to 68 when we're home, and back down to like 65 when we're asleep.

Ours is set at 68 from 5 am till 10 pm, and 62 from 10 pm till 5 am.  If I'm mad at my wife I set it to stay at 62 when I leave for work at 6:30 and shes still asleep.

We have natural gas, but the difference the first month was about 30 bucks.

[shmokes]

The ones at Home Depot say they're compatible with pretty much everything, but my friend just put a new furnace/air conditioner in his house and according to Traine the only ones that will work with his system are ones made by the company just for it and cost like $400  (I think mine was like $70)

[shmokes]

You could also look into X10....they make a lot of home automation stuff.  My father-in-law turns the heat on in the cabin just outside of yellowstone remotely about 6-8 hours before arriving because it takes so long to heat up.  There's a software program that lets you do detailed scheduling for all of your X-10 equipment.  Other companies make much better stuff, but the X-10 stuff is really affordable.

(yes....it's the company that makes the little cameras that you can set up to spy on hot chicks in your swimming pool)

[Bones]

I would be happy to ship boxes of warm air to you from Australia if you cover the freight plus a small administration fee for my time.

[Zakk]

I would be happy to ship boxes of warm air to you from Australia if you cover the freight plus a small administration fee for my time.

lookw buddy, keep your boxed dingo farts to yourself, ya freak.

[xar256]

You could certainly take the DiY approach to Aeroseal.  Pick up some real Duct tape <Not the cloth mesh stuff, the metal furnace duct tape> and tape every junction and screw hole of every length of pipe you can get at.
Do both the warm and cold air ducts.  That in itself will make a difference in making the warm air go where it's supposed to. 
As I'm renovating my place, I'm actually opening up all my walls and doing that, so ideally there shouldn't be any length left unsealed when I'm done.

I've also read the adding insulation around you heating ducts will help keep more the the warm air in the pipe too, so I'll probably throw some R-12 batts around the pipe as I'm going.  (In the long run, it may not be quite as thorough as the Aeroseal, but it'll cost a lot less and still help)

Some reading

I don't know how old your furnace is either, but when it comes time to change it out someday, you may want to consider going to a Geo-thermal heat pump...They have models that will adapt to forced air heating systems, so once installed (Not cheap) you're only paying the electricity for the pump to pull water up from the ground, and a fan to push the heat through the system.  (Rumor has it it can cut costs 50-70%) and you don't need much land anymore as a pipe can be installed vertically nowadays and not tear up the whole yard.

If it can heat a home in Winnipeg winters, it can keep you warm where you are     (Granted this is if you plan on staying where you are long term)

Oh yeah...Dryer venting inside -> iffey for 2 reasons (Carbon Monoxide is not really a concern for electic as stated already) Moisture - already mentioned, and air quality, even though the dryer has a lint trap, some lint and dust still manage to pass through...You'd just be adding that stuff to your indoor air. (Although there apparently are kits available to help cut back on that even farther - But it may be against codes in you area).

Then there's always the usual add more insulation everywhere you can thing...I'm sure that's been done to death already.

Food for thought,
Xar256

[JackTucky]

If you have a heat pump, or dual fuel system, the thermostats in the front at HD aren't the ones you need.  Trust me, I've returned a few.

Jacktucky

[DrewKaree]

Home Depot has a super-sweet touch screen model that lights up too.  If you're talking about how to tell if it'll work with your system, unless you have baseboard heaters (I think they're 240v), any of them will work.  I dunno what that Traine unit has that makes it incompatible with anything OTHER than their programmable thermostats, but I'd bet it has something to do with the unit NOT being warrantied unless it's used with Traine's thermostats (which is another reason the damned things are $400 )

As for your wiring hookup, they'll have 3-5 wiring hookups that you might have, none of which will probably match up color-wise or look like anything there, but it's all pretty easy to figure out if you can follow the simple directions they include.  A thermostat is NOT hard to figure out.

DON'T get a programmable thermostat that only has 1 setup.  Look for the multi-program setups.  The single setup units are only a step above the regular thermostat you have right now, and are frustrating in that you'll forever wish you'd have saved the money you pissed away on that unit and spent it on a better unit. 

[Santoro]

The major issue with a dryer vent is that lint is expelled.   I'd bet money that a heat exchanger would get gummed up with lint within a week.  I was just reading up on venting dryers, and they say not even to use dampers in the ducts because the lint would get  hung up on it.

[DrewKaree]

I wonder if throwing in one or more additional "lint screens" in the ductwork between the dryer and heat exchanger would help the problem.  Like finer mesh if more than one were used.  Something like a regular screen for the first one, a fiberglass-type one (they tend to be smaller openings) for the second....like that? 

[JackTucky]

Home Depot has a super-sweet touch screen model that lights up too.  If you're talking about how to tell if it'll work with your system, unless you have baseboard heaters (I think they're 240v), any of them will work. 

That will work with my heat pump system?  The one that's not dual fuel?

sweet

jacktucky

[DrewKaree]

I don't think heat pumps work with programmable thermostats at all.  I lived in NC and had one, and I seem to remember someone telling me that the heat pump works differently than a regular furnace.  It was something like either it wouldn't benefit from one of those types of thermostats or they didn't make 'em to work with their mechanisms for some reason.  I can't remember what the heck it was, but heat pumps are also included with the suck-diddly-uck-ness of baseboard heaters.

[danny_galaga]

Just get an air-to-air heat exchanger and a small fan.  The air streams (inside and dryer) would never mix.

What is an air to air heat exchanger?

just think VW heaters. or small aircraft heaters for that matter. there is a shroud over the exhaust pipe so that air drawn through it will be warmed by the exhaust. this could work quite well for your idea. good for you for conserving energy chad! i had you down as another resource hungry, capitalist running dog imperialist! 

[danny_galaga]

The major issue with a dryer vent is that lint is expelled.   I'd bet money that a heat exchanger would get gummed up with lint within a week.  I was just reading up on venting dryers, and they say not even to use dampers in the ducts because the lint would get  hung up on it.

in addition to my comment on the VW/aircraft type heat exchanger. everything runs INSIDE the exhaust, no lint OR humid air to worry about. i ahven't had a close look at the pic posted earlier but if lint were to clog it up then it sounds like it might be the reverse of this type...

[ChadTower]

good for you for conserving energy chad! i had you down as another resource hungry, capitalist running dog imperialist! 

Yeah, not me.  I'm all about efficiency and recycling.  I was when I was a teen, then I went to UMass, and they're worse than the Borg.

[shmokes]

My friend's Traine is a heat pump or has a heat pump or however it works, so I guess that's why.  At any rate Traine does offer a programmable thermostat, but as I said it's extremely expensive.

[JackTucky]

I don't think heat pumps work with programmable thermostats at all.

My downstairs dual fuel unit has a programmable.  I want one for upstairs.


Jacktucky

[ChadTower]

Anyone have any rough data on whether or not you would save on heating costs by finishing the basement?  I bet we lose a lot of heat through the floor and such...

[ErikRuud]

I don't think will help your bills any, unless you are actively trying to keep your unfinished basement as warm as the rest of your house.

I don't have actual data, but we finished our basement two years ago and it has not made any noticible difference in the heating bills.

The basement is now a nice place to hang out.

I alway kept the vents closed in the basement and I still do.  It says warm enough on it's own.

[DrewKaree]

The only money you're going to save by finishing your basement, as Eric pointed out, is the amount of money you MIGHT have spent if you were trying to heat it.  Heat rises.  That means it might feel like your floors were colder, but you wouldn't turn up the heat just to heat your floors, and it's not going to make that much of a difference if your basement isn't finished.  If you had just a crawlspace and didn't finish or close it off, that might make a bigger difference.

Finishing off your basement simply turns that area into liveable space.  Insulating it saves you money in that you won't have the heat turned up higher to heat that area.  Insulate enough, and that can be the warmest spot in the house.  My brother-in-law's house - that's the case.  His basement is easily 5 degrees warmer than the upstairs due to all the insulation and his basement retaining so much more heat than the upstairs.