Install StovePipe/Direct Vent Now?

[Spudland_Dave]

Last night I was installing insulation and got to thinking...should I install my stovepipe or direct vent now before I insulate & sheetrock it? Seems to me it would be a whole lot easier right now? Only problem/issue is I don't have my furnace yet. I would PREFER a ceiling mounted hot air unit to save floor space, but realistically its gonna be hard to justify it when I can get Miller hot air units for 2-300 bucks all day long.

I guess the question could be the other way as well...how hard is it to install a flue After the fact?

 

[Highbeam]

I think this depends on the shape of the attic above. If you will be forced to work in a really short part of the attic like down near the soffits then it is much easier to install the flue before the ceiling goes up. If your flue enters and exits in a tall part of the attic then it can be better to do it after the ceiling is up so that you can cut the hole in the sheetrock.

 

[Steve in Mi]

I thought 'direct vent' meant thru the wall directly behind the furnace. If it is this type I would leave a portion of the wall cavity open until it is fitted up to the furnace then pull the furnace out and make the final drywall install around the flu pipe.

 

[Highbeam]

No, you can direct vent things vertical too. Maybe you're thinking power vent but even with that, you can shoot it out the roof as well.

 

[Spudland_Dave]

I think this depends on the shape of the attic above. If you will be forced to work in a really short part of the attic like down near the soffits then it is much easier to install the flue before the ceiling goes up. If your flue enters and exits in a tall part of the attic then it can be better to do it after the ceiling is up so that you can cut the hole in the sheetrock.

"Full" attic above...12' in the middle of the building is finished, full 8' Height, Kinda too late in terms of the ceiling, its 100% strapped/sheetrocked/insulated. I didn't give it much thought because cutting the roofing wasn't something I'm interested in doing. My roof is new, is perfect, and why would I want to mess that up?

I thought 'direct vent' meant thru the wall directly behind the furnace. If it is this type I would leave a portion of the wall cavity open until it is fitted up to the furnace then pull the furnace out and make the final drywall install around the flu pipe.

Yeah that's what I was thinking...Direct Vent or Power Vent thru wall (see above comments about putting holes in my virgin roofing)

No, you can direct vent things vertical too. Maybe you're thinking power vent but even with that, you can shoot it out the roof as well.

Wall venting is what I want... after much opinions from people I called my heating guy. He wouldn't suggest power vent with the furnace I wanted...suggested a ceiling mount Direct Vented Gas Hot Dawg or Reznor, problem is wife wants NO PART of Gas anything. Looking it up and researching it, I really like that idea too...but she said again tonight...The Devil will be skating in hell before you put a gas furnace in. Wish I could ***** more about it, she's left me alone with my garage pans up till now (minus the commandments about roofing/trim/siding must match house...which I was onboard with)..

So tomorrow I'm gonna call him back and see if I cant schedule a visit from him...talk about my options...get pricing, etc..

 

[sands35]

Have you done the math for your local area on gas vs electric costs vs wood? Might sway your wife.

Anyway, I'd do as much as you can before your sheet rock and then think hard about how you will service / inspect the ducts after the sheet rock is up.

 

[Highbeam]

So if you can't use gas then what do you plan to use? Wood? Then you should be only considering a vertical chimney through the roof.

 

[brewchief]

If your thinking oil then go ahead with a proper all fuel vent now, a powerventer on an oil furnace just adds one more thing to go wrong.

FWIW I would much rather cut in a new flashing when the weather is warm and dry then when it's cold and wet and you are trying to get heat going right away.

Is the roof metal or shingled? With proper planning a long term leak free penetration is very possible.

 

[Full Size 66]

Really, no gas? I do not understand this. Maybe in your area it isn't affordable or something. I live in the land off hydroelectric and i couldn't afford electric heat in the shop. I am using a reznor with powered vent with a side wall exit. To answer the original question it is OK either way to do it before or after drywall, and your already there. Mine is going to be cut in this week right before I put in the insulation and drywall.

 

[Spudland_Dave]

Have you done the math for your local area on gas vs electric costs vs wood? Might sway your wife.

Electricity is VERY expensive here in the New England Grid. Cant do wood...no solid fuel allowed by most insurance co's in non-attached structures. Technically not gas...LP.
Even then, I think if I told her I could get a free heater and fuel would cost no more then $20.00 a year guaranteed, she'd still say Oil.

So if you can't use gas then what do you plan to use? Wood? Then you should be only considering a vertical chimney through the roof.

Here in New England Oil is King. Gas is a novelty in only a couple cities and LP is spotty.. As mentioned above Solid Fuels are not allowed by most insurance companies in non-attached structures, otherwise my plans for the garage would have been TOTALLY Different. I would have installed a Coal boiler in the garage, plumbed it to the house so I could heat both garage & house with the coal boiler in the garage.

If your thinking oil then go ahead with a proper all fuel vent now, a powerventer on an oil furnace just adds one more thing to go wrong.

FWIW I would much rather cut in a new flashing when the weather is warm and dry then when it's cold and wet and you are trying to get heat going right away.

Is the roof metal or shingled? With proper planning a long term leak free penetration is very possible.

Roof is asphalt shingles, I agree with you...I feel the same about cutting into the vinyl siding, in the summer heat its nice & pliable.

Really, no gas? I do not understand this. Maybe in your area it isn't affordable or something. I live in the land off hydroelectric and i couldn't afford electric heat in the shop. I am using a reznor with powered vent with a side wall exit. To answer the original question it is OK either way to do it before or after drywall, and your already there. Mine is going to be cut in this week right before I put in the insulation and drywall.

I'm from the land of Oil heat...ie new England. Plus to compound things, she's always felt sketchy about LP/Gas heat...then a couple weeks ago this happened: http://www.wcsh6.com/news/article/247782/2/Fire-Marshal-Propane-caused-Yarmouth-explosion
My chances are slim to none now.. as I said...propane could be free and heating oil 5.00 a gallon, wouldn't change things I fear.

 

[Highbeam]

Really, no gas? I do not understand this. Maybe in your area it isn't affordable or something. I live in the land off hydroelectric and i couldn't afford electric heat in the shop. I am using a reznor with powered vent with a side wall exit. To answer the original question it is OK either way to do it before or after drywall, and your already there. Mine is going to be cut in this week right before I put in the insulation and drywall.

I too live in the land of hydro and our power is cheap at 10 cents per kwh, but unless you have NG then your gas cost is actually higher per unit of heat. Remeber, electric is 100% efficient and gas is not.

 

[Spudland_Dave]

I too live in the land of hydro and our power is cheap at 10 cents per kwh, but unless you have NG then your gas cost is actually higher per unit of heat. Remeber, electric is 100% efficient and gas is not.

So riddle me this then...how much electricity does a normal unit heater which could heat a 30x50x10' high take? with only 100A there...doubt I'd even have enough juice there to make it work?
Met with my heating guy today...he was unable to convince the wife to go LP/Gas...so he will research what my options are in oil...in terms of direct/power vented units.

 

[Highbeam]

So riddle me this then...how much electricity does a normal unit heater which could heat a 30x50x10' high take? with only 100A there...doubt I'd even have enough juice there to make it work?
Met with my heating guy today...he was unable to convince the wife to go LP/Gas...so he will research what my options are in oil...in terms of direct/power vented units.

How many btus do you need? I suspect a 40k btu unit? Let's assume that since we have no other choice.

If you do that with resistance heat it would take 3.41 btu per watt so 11730 watts and divide that by 240 volts means a 49 amp device so you would need 6 gauge wire and a 60 amp breaker. Pretty big but at 15 cents per kwh will only cost you 44$ per million btu.

Propane at 2.50$ per gallon would cost 36$ per million btu. That's with a crappy 78% efficient reznor type heater.

Now oil isn't bad at today's price. Oil at 4$ per gallon would cost you 37$ per million btu using the same 78% efficient device.

In my area we only pay 10 cents per kwh so my cost is only 29$ per million btu.

 

[Spudland_Dave]

How many btus do you need? I suspect a 40k btu unit? Let's assume that since we have no other choice.

If you do that with resistance heat it would take 3.41 btu per watt so 11730 watts and divide that by 240 volts means a 49 amp device so you would need 6 gauge wire and a 60 amp breaker. Pretty big but at 15 cents per kwh will only cost you 44$ per million btu.

Not quite sure yet what I need...rough online calculators peg it at 75k-ish BTU....heating guy will be doing a Real calculations and getting back to me, but from hearing the 50A requirement for a tiny 45k unit which I don't think is even close enough, I think electric is out from a purely "mechanical" standpoint.

 

[Highbeam]

Not quite sure yet what I need...rough online calculators peg it at 75k-ish BTU....heating guy will be doing a Real calculations and getting back to me, but from hearing the 50A requirement for a tiny 45k unit which I don't think is even close enough, I think electric is out from a purely "mechanical" standpoint.

I do believe that you are right, lots of amps to match what people typically use for reznor type heaters.

It's not all or nothing, if electric is as cost effective for you as it is for me then you can put in a cheap electric heater which will do the job for a good part of the year but when it gets really cold you could fire up the big oil job.

Dual fuel is what you'd have. Electric is very versatile in that it needs no exhaust ducting and you already have the fuel source wired to your building. Cheap install, cheap device.

 

[Spudland_Dave]

I do believe that you are right, lots of amps to match what people typically use for reznor type heaters.

It's not all or nothing, if electric is as cost effective for you as it is for me then you can put in a cheap electric heater which will do the job for a good part of the year but when it gets really cold you could fire up the big oil job.

Dual fuel is what you'd have. Electric is very versatile in that it needs no exhaust ducting and you already have the fuel source wired to your building. Cheap install, cheap device.

Yeah...I hear ya. Actually I had my garage design done in my head for 5+ years before we built...i'm all screwed up because of changes in plans. All along I was wanting to put a Coal boiler in the garage (Detached), plumb it to the house so I could heat the house AND garage with Coal in the winter. Come to find out, cant do the solid fuel in the garage...

 

[Highbeam]

Yeah...I hear ya. Actually I had my garage design done in my head for 5+ years before we built...i'm all screwed up because of changes in plans. All along I was wanting to put a Coal boiler in the garage (Detached), plumb it to the house so I could heat the house AND garage with Coal in the winter. Come to find out, cant do the solid fuel in the garage...

My insurance company said that they would drop my house and shop if they found a solid fuel burner in my "outbuilding". The county would permit it though. I'm torn. I love wood heat. Supposedly some insurance companies are okay with it.

 

[Spudland_Dave]

My insurance company said that they would drop my house and shop if they found a solid fuel burner in my "outbuilding". The county would permit it though. I'm torn. I love wood heat. Supposedly some insurance companies are okay with it.

How it came about was my FIL had a random inspection by his Homeowners Ins...his garage had a full Brick Chimney, nice/maintained wood stove, never a problem in the 30+ years (stove was newer, chimney had been relined once)...no reason it was a problem. To keep the heat they figured it was a good opportunity to shop around insurances, keep the stove and maybe save a few bucks, nobody would touch it with a 10' pole, so they had to take out the stove. I called my insurance for the heck of it...same deal, NO solid fuel in a detached. In our attached garage...no prob, I could burn baby kittens with no problem.

 

[Highbeam]

And the whole time, had your FIL's barn burnt down, do you suppose his policy would have paid out since he had violated a rule?

 

[Spudland_Dave]

And the whole time, had your FIL's barn burnt down, do you suppose his policy would have paid out since he had violated a rule?

Good question...the key here is when the policy was written years ago, was solid fuel ok?
I suspect that when the policy was written it was OK...I know it was news to them, they weren't willfully breaking protocol...along the way things changed and it became against policy.

Knowing insurance companies...they wouldn't have paid.

 

[Highbeam]

Knowing insurance companies...they wouldn't have paid.

And that should be your worst fear. No pay out for the loss or for any injuries or death that you are deemed liable for due to your "illegal" act.