# Furnace in the attic



## ModernStyle (May 7, 2007)

I have been painting my parents house about once every 3 years for them, it is aluminum siding with wood trim. A few years ago they wanted central air so my dad had a new furnace installed in the attic, the old one was the kind with the little radiators along the baseboard. So the guys came out and ran new duct work and installed the furnace. 
Since the new furnace had been in the wood overhangs have started to rot and the paint just peels off of them in sheets, all the way to the raw wood, which is way under any of the coats I have applied.
I think that it is the furnace in the attic that is causing the problem and that the roof will have to be vented better then originally to accommodate the furnace being up there. The Overhangs have the rectangle style vents in them and I have made sure that they are open, so I figure with the added humidity of the furnace and duct work running thought the attic that new vents are needed.
This is not my trade so I really didn't know a whole heck of allot about this sort of thing. I seen WarnerConst. had some venting issues on one of his projects and that got me thinking that it could be my parents problem also. I am not going to add the vents myself, too afraid I will make the roof leak, so maybe I should just hire Warner, he is a few miles up the highway from me.


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## WarnerConstInc. (Jan 30, 2008)

Hey, sounds fishy to me. Where does the furance exhaust to? No insulation packed in the eaves since you cleared the soffet vents right?

PM if you have any questions.


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## ModernStyle (May 7, 2007)

I will check it out this weekend and see if I can get some pictures of what the set up is over there. Like I said I am a painter so some pics might help guys who know more about this sort of thing then me trying to describe it.
I was kinda putting it off for a few weeks untill I got done with my kitchen, but my dad keeps bugging me about it so I figured I would post something just so I could give him some info. If it comes down to hiring someone to fix it and you got the time I will recommend you Warner, I would rather it goes to someone I know even online then to some hillbilly friend of my uncle or something like that.


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## Deadhead Derek (Dec 3, 2008)

gas or electric? make up air ducting? 90% effic.?


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## mrmike (Dec 9, 2008)

Wow, Talk about in-efficiency !!! Whoever talked them into that? The worst possible place to ever put it. I would hate to pay those bills. Cold surronding the heating system in winter, hot around the A/C in summer- Not only that, but other Problems like you described--------- One Big Nightmare !!


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## ModernStyle (May 7, 2007)

Deadhead Derek said:


> gas or electric? make up air ducting? 90% effic.?


 
It is a gas furnace, thats pretty much all I know about it untill I get over there this weekend.
I dont know who installed it.


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## WarnerConstInc. (Jan 30, 2008)

Its done all the time around here like that.

Sometimes without regard to what other effects it will have down the road.


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## dubz (Sep 8, 2008)

WarnerConstInc. said:


> Its done all the time around here like that.
> 
> Sometimes without regard to what other effects it will have down the road.


Is that because you have a lot of slab on grade construction, instead of on a foundation? 

It sounds like an improper exhaust venting problem with that furnace I would think, MS


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## WarnerConstInc. (Jan 30, 2008)

dubz said:


> Is that because you have a lot of slab on grade construction, instead of on a foundation?
> 
> It sounds like an improper exhaust venting problem with that furnace I would think, MS


That and a combination of houses that had all electric heat and no AC.

When someone wante to add AC or a whole new system, it is easier to put the unit in an attic.

There is a furnace exhaust issue some where, where they ran that who knows.

It works well if everything is insulated properly.

Most new houses with slabs have the furnace in the garage, just about like having it in the attic at times.


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## Magnettica (Dec 19, 2006)

I see full furnaces and air handlers in the attic all the time. 

Just because it's hot in the summer and cold in the winter DOES NOT mean the furnace will work harder because of ambient temperature because that's what a thermostat is for and of course that gets installed on an interior wall.


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## mrmike (Dec 9, 2008)

Magnettica said:


> I see full furnaces and air handlers in the attic all the time.
> 
> Just because it's hot in the summer and cold in the winter DOES NOT mean the furnace will work harder because of ambient temperature because that's what a thermostat is for and of course that gets installed on an interior wall.


???? A thermostat doesn't care what energy is lost on the way, it will just make them run longer to get to it's Temperature setting. If Energy is lost on the way & IT DOES make the furnace or A/C work harder to meet the thermostat's demand !! In Attics, Ambient Temps are more extreme, & just because it's hotter in the summer, & colder in the winter, there will be more losses........... & the losses are not going into the house or garage or furnace room,etc.


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## dubz (Sep 8, 2008)

Air handlers in the attic sure, but for service, noise, vibration, replacement, and less line to feed the thing, having it in the basement is optimum.
Air handler coils have to be protected from freezing and most attics aren't heated. Anti-freeze rots the copper lines out quicker.


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## ModernStyle (May 7, 2007)

The house is on a slab, thats why they stuck it in the attic. There was a small furnace room, very very small, I guess the new furnace didn't fit in there or maybe it just wouldn't have worked in there. Personally I would have installed it in the garage just so servicing the unit would be easier. The house was built in the 50's and since the furnace was installed I have had to deal with more and more nail pops in the ceilings. Not sure if that is from the added weight of the furnace and the people moving around up there when servicing it, or if it is also related to the chance that the thing is not vented correctly.
The roof is less then 10 years old and I have seen no evidence that it leaks anywhere. Thats why I keep coming back to the idea that something with the vents must be the problem.


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## dubz (Sep 8, 2008)

There is a limit to the length of the exhaust pipe before it needs to be power vented. Do they have a CO detector in the house? I'd be concerned about that.

Nail pops due to vibration when the thing runs prolly


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## boman47k (Oct 13, 2006)

Guestion then a statement.

Painting every three years? Is that by someone's choice or is it an adhesion problem?

I have a split system with the heat in the attic. I have noticed cold air coming from the registers before heat. I always thought it weird that the system blows cold air then has to replace the heat loss due to emptying the ductwork of its cold air. I assumed the installers did not use insulated ductwork except for the flex stuff running from the main duct.


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## ModernStyle (May 7, 2007)

They have changed the color and added some changes, so it comes out to me painting the house about every 3 years for the last 9 or so years.


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## WarnerConstInc. (Jan 30, 2008)

Technically I think they are supposed to suspend the units or install a rubber pad to isolate the unit from the framing.

Paint peeling on soffets is because of moisture inside the eaves.

One guy around here was notorious for filling the insides of wood soffets with cellulose.

Paint would peel off down to the bare wood in a matter of months because of this.

I have dealt with a few overhangs on some houses he did that to and for the most part I had to tear them apart and rebuild. They rotted from the inside.


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## ModernStyle (May 7, 2007)

That might be the problem, he told me he checked the vents and soffits but maybe not. I cleared one in the front when I had a buddy replace a board for him, but my dad assured me that he had been up there and that the rest were clear. I will try to squeeze in the time to stop by there tomorrow and see whats up, I swear that from now on my parents are not allowed to have anyone work on their house without my permission.


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## WarnerConstInc. (Jan 30, 2008)

Now remember, I think the bigger issue of concern is the actual ventilation of the furnace itself, just giving you a few things to look for and maybe eliminate.


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## Magnettica (Dec 19, 2006)

mrmike said:


> ???? A thermostat doesn't care what energy is lost on the way, it will just make them run longer to get to it's Temperature setting. If Energy is lost on the way & IT DOES make the furnace or A/C work harder to meet the thermostat's demand !! In Attics, Ambient Temps are more extreme, & just because it's hotter in the summer, & colder in the winter, there will be more losses........... & the losses are not going into the house or garage or furnace room,etc.



All the t-stat cares about is, "hey I'm cold, satisfy me". 

Makes no difference what the temperature is where the furnace is located.


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## MEL (Apr 7, 2007)

*Exhaust fumes*

Furnace exhaust fumes contain water. Maybe the vent pipe is disconnected or leaking. It could be a safety hazard due to carbon monoxide.


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## trptman (Mar 26, 2007)

sounds like this has been answered pretty well with what info you have so far, but for my 2 cents, It kind of sounds like they added the furnace and didn't run the exhaust vent outside. sounds like they are maybe letting it vent into the attic counting on the attic ventilation to get rid of the fumes?
If that's the case, that needs fixed. It would account for the added moisture you are running into.
just a thought.
or the vent came apart somehow and is spewing moisture into the attic maybe


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## ModernStyle (May 7, 2007)

So i crawled up in the attic today. As far as the furnace goes I dont think it is the problem, it vents out about 3 feet above the furnace, straight shot with no turns. Thr duct work looks kinds like dryer vent material, I dont know what you would call it, I am a painter. 
After being up there I definetly think it is the insulation my dad had blown in a few years back. I dont go in many attics, but from what Warner was saying I guess the insulation should stop at some point before entering the soffits. Well it doesnt it kind peters off before it gets there but it looks like there is still a good 2 inches of insulation covering the vents. I didnt have any kind of dust mask with me so I tied a rag around my face and used a rake to pull the insulation back between a set of trusses, but I am assuming it is that way all around.
Now my question is if I pull the vents on the outside and remove the insulation from around the vents would I have to build a barrier of some sort to make sure the vents stay open? I realize that there is no wind up there and the stuff should for the most part stay put, but do they normaly put something there to keep it open?
I wanted to get some pics of it but my camera batteries were dead and I didnt know it. I should be able to open the vents on my own I figure but I will probably end up having them hire someone to come out to inspect and replace the wood that is bad. If anyone has a pic of how an insulated attic should look please post it. Damn painters never go into attics except after a fire to spray it down with BIN, atleast that is the only time I have ever had to crawl in one.


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## MEL (Apr 7, 2007)

*baffles*



ModernStyle said:


> So i crawled up in the attic today. As far as the furnace goes I dont think it is the problem, it vents out about 3 feet above the furnace, straight shot with no turns. Thr duct work looks kinds like dryer vent material, I dont know what you would call it, I am a painter.
> After being up there I definetly think it is the insulation my dad had blown in a few years back. I dont go in many attics, but from what Warner was saying I guess the insulation should stop at some point before entering the soffits. Well it doesnt it kind peters off before it gets there but it looks like there is still a good 2 inches of insulation covering the vents. I didnt have any kind of dust mask with me so I tied a rag around my face and used a rake to pull the insulation back between a set of trusses, but I am assuming it is that way all around.
> Now my question is if I pull the vents on the outside and remove the insulation from around the vents would I have to build a barrier of some sort to make sure the vents stay open? I realize that there is no wind up there and the stuff should for the most part stay put, but do they normaly put something there to keep it open?
> I wanted to get some pics of it but my camera batteries were dead and I didnt know it. I should be able to open the vents on my own I figure but I will probably end up having them hire someone to come out to inspect and replace the wood that is bad. If anyone has a pic of how an insulated attic should look please post it. Damn painters never go into attics except after a fire to spray it down with BIN, atleast that is the only time I have ever had to crawl in one.


You should have baffles to hold back insulation.


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## ModernStyle (May 7, 2007)

There are baffles but the pic you posted shows fiberglass insulation folding back under the baffle, there is none. The baffles are stapled to the roof but the insulation is just blown right in under them. It looks like they just stapled up the baffles like a decoration then just blew the insulation any place they wanted.


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## WarnerConstInc. (Jan 30, 2008)

That would be a lazy insulation company for you.

Your goning to have to stuff something under the baffles so when you push the blown-in back, it stays out of the over hangs.

That is your soffet paint peeling problem right there!!


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## dubz (Sep 8, 2008)

That promo picture is pretty illustrative of the problem. It's funny that they show some blown-in actually covering up some of the air flow. It's a little bit tricky leaving the airflow for your roof while blocking it from your house.


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## WarnerConstInc. (Jan 30, 2008)

dubz said:


> That promo picture is pretty illustrative of the problem. It's funny that they show some blown-in actually covering up some of the air flow. It's a little bit tricky leaving the airflow for your roof while blocking it from your house.


Agreed, and its a PITA climbing into the ends of the rafter bays to do it!!


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## ModernStyle (May 7, 2007)

I am trying to get them to call the company who insulated the house about this, my mom said it was less then 2 years ago, so I don't know what will come of it. If they don't call them then I will, even if they do I still might call them. I am allot better at letting people know how pissed I am then they are, they will just accept whatever they are told, I on the other hand will threaten to burn down houses and barbecue family pets.
My dad should be calling me later when he gets off work, hopefully he knows who insulated the house. 
The furnace set up actually looks pretty good up there, I thought they might be losing allot of heat in the ducts but the stuff that is up there is insulated so I guess that isn't a problem. The vent to the furnace looks good and was not loose at all. Not a very efficient furnace according to the little yellow sticker on the front, but the company that installed it seems pretty reputable.


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## Lew (Dec 3, 2006)

ModernStyle said:


> I on the other hand will threaten to burn down houses and barbecue family pets.


LMAO... I hope the insulation company will have some moral backbone and fix the issue.


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## trptman (Mar 26, 2007)

If the soffit drops off like that diagram a few posts back, you are in for some fun getting the insulation back out of there.
If the soffit is more even with the attic "floor" you could maybe just reach out there with some kind of rake or something and pull the insulation back off the soffit. save yourself some work. only problem with that is that if you ever add more insulation, it's going to cost more because whoever does it will have to put some kind of baffle up to keep it from blowing out there again.


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## BigMikeB (Aug 1, 2007)

mrmike said:


> ???? A thermostat doesn't care what energy is lost on the way, it will just make them run longer to get to it's Temperature setting. If Energy is lost on the way & IT DOES make the furnace or A/C work harder to meet the thermostat's demand !! In Attics, Ambient Temps are more extreme, & just because it's hotter in the summer, & colder in the winter, there will be more losses........... & the losses are not going into the house or garage or furnace room,etc.


No matter where the furnace or airhandler is located the ductwork is run through the attic 50% of the time and ambient temp has little to no effect on the air in the ductwork providing it is properly sealed and insulated. The only air being pulled into the ductwork is return air and that is from living space and not the space around the furnace unless it is improperly installed. Newer sealed combustion furnaces give off little heat to the surrounding area. As for combustion air with a gas furnace, it is better to be in a space like a ventilated attic than to take the air from a living space. Maybe up in the hills people put a furnace in the living room and have duct work exposed in living space but in civilized areas the furnace goes in the attic, basement, or garage.


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## BigMikeB (Aug 1, 2007)

dubz said:


> Air handlers in the attic sure, but for service, noise, vibration, replacement, and less line to feed the thing, having it in the basement is optimum.
> Air handler coils have to be protected from freezing and most attics aren't heated. Anti-freeze rots the copper lines out quicker.[/quote]
> 
> 
> What planet do you live on? I have been working on commercial buildings and schools that are running propolene glycol in the hydronic systems for the last 20 plus years and have never seen a pipe rotted out in any of their systems. The only downside to glycol in the system is it isn't as good a heat transfer fluid as plain water. I have never seen an attic mounted coil freeze up that wasn't caused by an outside air damper staying open not the ambient temp of the attic.


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## mrmike (Dec 9, 2008)

BigMikeB said:


> No matter where the furnace or airhandler is located the ductwork is run through the attic 50% of the time and ambient temp has little to no effect on the air in the ductwork providing it is properly sealed and insulated. The only air being pulled into the ductwork is return air and that is from living space and not the space around the furnace unless it is improperly installed. Newer sealed combustion furnaces give off little heat to the surrounding area. As for combustion air with a gas furnace, it is better to be in a space like a ventilated attic than to take the air from a living space. Maybe up in the hills people put a furnace in the living room and have duct work exposed in living space but in civilized areas the furnace goes in the attic, basement, or garage.


I am not a hvac guy, Everyone has their own opinion, but I take offense to your last comment- What are you saying??? We have people like you come up here & find out their opinion isn't the only one in the world. 
Here is one I found on Contractor Express.
*Don't Install HVAC Equipment Or Ducts in an Attic*
An attic is almost as cold as the exterior in winter, and can be much hotter than the exterior in summer. While attic floors are often insulated to R-38, attic ducts are usually insulated to a measly R-4 or R-6.

During the summer, the difference in temperature between the cool air in the ducts and a hot attic is much greater than the difference in temperature between the indoor and the outdoor air. So why does attic ductwork have so much less insulation than a wall or a ceiling?

Moreover, the air in a supply duct is at a much higher pressure than the air inside a house. Since most duct seams leak, a significant portion of the volume of air passing through attic ducts usually leaks into the attic. Any leaks in return ducts allow the blower to pull hot, humid attic air into the air handler.

Installing a furnace or air handler in an attic causes even more problems than merely installing ductwork there. A recent study found that the leakage of a typical air handler, coupled with the leakage at the air-handler-to-plenum connection, amounts to 4.6 percent of the airflow on the return side. If the air handler is installed in an attic, a 4.6 percent return-air leak can produce a 16 percent reduction in cooling output and a 20 percent increase in cooling energy use. Any duct leakage would make the situation even worse.

In most homes, HVAC equipment and ductwork belong in the basement or crawlspace. If it's absolutely necessary to build on a slab, include a utility room for HVAC equipment and install ducts in air-sealed interior soffits.


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## MEL (Apr 7, 2007)

*Soffit vents*

You may have to tear down the soffit to open up ventilation. Or cut through it with a saw. Then you could remove the insulation that is in the overhang.

You could install continuous vented soffit material made out of vinyl.

You should also check the plywood in the attic to see if it is covered with mildew.


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## ModernStyle (May 7, 2007)

Well we got all the insulation pulled back and the vents are now open. Thanks to everyone who gave me some input.


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## BMAN (Aug 21, 2006)

I understand all the talk about the ventilation and all that, i even talk about it with my customers all the time. why hasnt anyone asked what kind of paint you are using and what was on the house in the past. I have seen new acrylics rip the old paint right off the house on a few occasions. ::: New Acrylics (especially self primers) are so flexible that they will force the old oil and enamel coatings right off the house. It could be a cohesion isssue that is being made worse by the insulation issue.


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## trptman (Mar 26, 2007)

mrmike said:


> An attic is almost as cold as the exterior in winter, and can be much hotter than the exterior in summer. While attic floors are often insulated to R-38, attic ducts are usually insulated to a measly R-4 or R-6.


not if you do what I did in my attic...after the furnace was installed that heats and cools the upstairs (another one in the basement), I completely buried all the insulated flexible duct with cellulose insulation. so the duct is essentially insulated to the same extent the whole attic is...


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## WarnerConstInc. (Jan 30, 2008)

Thanks for the info MrMike but, I think not having duct work in an attic is something that is hard to avoid. Duct work in a slab is pretty cool in the winter, and crawl spaces are pretty cool. Attics bad, my house has upstairs duct starting in basement and going through 2 different attic spaces before exiting in the ceilings upstairs, it does just fine.


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## Magnettica (Dec 19, 2006)

That picture/ diagram is spot-on. 

Credit Mr Mike for at least defending his position. 

Learn something everyday here.


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