Air Sealing an Old Wood Fireplace

[pnear]

Thanks in advance for all of the information I've been able to glean from the contributors to this forum! I haven't been able to find the answers that I'm looking for though, so I'm hoping that by laying out the questions you can help me in my quest for knowledge.

My home is about 25 years old, and I just went through an energy audit where the fireplace was noted as an issue for air leaks. I already knew this, as we get a nasty charred wood smell from the fireplace when the clothes dryer is on. We had the local chimney guy out to take a look, and he noted that the damper was off of it's track made a quick adjustment and charged us $100. The problem remains.

Based on my reading, here are some other things I'm considering:
- Get a new set of glass doors. The set I have doesn't appear to have any sort of insulation on either the frame or the doors, would spending $300 on a new door like the ones on lowes.com help or is this just wasted effort?
- Get a new high efficiency insert. I can get a $750 gov't rebate, but the cost is getting outside of my available budget especially considering the other work I'm doing on the house (quotes in the $2500 - 3500 range).
- Get a cheap insert and attempt the install myself (local hardware store has a Drolet for $1100). But I'm assuming there's more than meets the eye there, not the least of which is having to install a liner in my exterior chimney (seems complicated).
- Build a blockoff plate for when not in use. I think this idea is invalid, blockoff plates seem to be more as an intermediate piece after you've installed a new insert. But is there a way for me to insert something that's almost like a secondary damper when the fireplace isn't in use?
- Get an inflatable plug for the "off season" and for when the energy audit guy comes back. There's a $380 rebate I can get for air sealing, and I'm doing alot of work to fix leaks elsewhere in the home and would hate for the fireplace to negate all of that work (and lose me the rebate).

I love having a wood fireplace, but to be honest we only use it on weekends and during the fall/winter months which is why it's on the lower end of the priority list for the home renovations.

I'm certain I've missed or messed up my understanding of options, and I'm anxious to hear the group's thoughts.

Thanks,
Peter

 

[dave11]

I had a retractable chimney cap installed on the flue of my basement fireplace. It's on a cable coming down the flue into the firebox, from the outside area above the top of the flue, and pulling the cable seals the cap pretty well to the top of the flue. Should stop most backdrafting, and keep rain/snow out of the chimney, which would lead to less smell as well. Should also stop most or all the air escaping up the chimney in winter. When you want to use the fireplace, just release the cable, takes 2 seconds. It's adjustable, which should help with proper firing as well.

I have no experience with fireplace doors, but from what I've read, they're hard to make/keep airtight.

 

[fbelec]

putting in a stove or insert will not stop the smell because the stove or insert has a open air inlet that is open at all times and it might even make the smell worse. you might want to put in a makeup air vent next to your dryer. run a 2nd dryer vent in a u shape down and up the wall and leave the pipe open, so air will only come in when something is calling for it.

 

[semipro]

I had a retractable chimney cap installed on the flue of my basement fireplace. It's on a cable coming down the flue into the firebox, from the outside area above the top of the flue, and pulling the cable seals the cap pretty well to the top of the flue. Should stop most backdrafting, and keep rain/snow out of the chimney, which would lead to less smell as well. Should also stop most or all the air escaping up the chimney in winter. When you want to use the fireplace, just release the cable, takes 2 seconds. It's adjustable, which should help with proper firing as well.

I have no experience with fireplace doors, but from what I've read, they're hard to make/keep airtight.

Dave, could you share which brand/model you ended up with and how well its worked. I've been looking for one for our 2nd, seldom-used flue and there are a lot of different ones out there. Thanks.

 

[Later]

Dave, I had one of those top dampers and it worked well - until we had an ice storm that knocked power out and the @#%^# thing was frozen shut! I took it off.

 

[dave11]

I had a retractable chimney cap installed on the flue of my basement fireplace. It's on a cable coming down the flue into the firebox, from the outside area above the top of the flue, and pulling the cable seals the cap pretty well to the top of the flue. Should stop most backdrafting, and keep rain/snow out of the chimney, which would lead to less smell as well. Should also stop most or all the air escaping up the chimney in winter. When you want to use the fireplace, just release the cable, takes 2 seconds. It's adjustable, which should help with proper firing as well.

I have no experience with fireplace doors, but from what I've read, they're hard to make/keep airtight.

Dave, could you share which brand/model you ended up with and how well its worked. I've been looking for one for our 2nd, seldom-used flue and there are a lot of different ones out there. Thanks.

Semipro--I wish I could, but I don't have a model or brand name to give you. It was done by the sweep who inspected this house as the sale was going through, and since the damper over the firebox was bad, he suggested this arrangement. I didn't know much about fireplaces at the time, and so I just OK'd the install. The receipt doesn't name the brand. It's also very hard to access the top of the chimney, so I can't get it for you that way.

I'll say though it seems to be a quality product, and the install seemed fine. The bill was $350 including parts.

It's a square cap, sitting on what looks like a scissor-lift sort of spring, which is under upward tension. There's a cable running down from the cap through the flue into the firebox that mounts onto a bracket installed onto the brick on one side. The end of the cable is fitted with a notched chain which allows the cap to be opened through a range of heights, or pulled fully closed. Sorry I can't get you a name. But i'm perfectly satisfied with it.

 

[Later]

My sweep sold me one too. Worked well until ice - I gave it to the sweep who replaced it with the screen cap. Cast aluminum as I recall.

 

[dave11]

I have only adjusted mine once or twice, so I never had to worry about it getting frozen closed. But it seems like that would be indeed an issue for someone wanting or needing to use their FP as a significant source of heat. Might need to keep an eye of the weather, and leave it open if an icestorm is predicted.

 

[DAKSY]

Go here then shop around for the best price:

http://www.woodlanddirect.com/Chimney/Top-Sealing-Chimney-Dampers/Lyemance-Damper-Energy-Saving

 

[Cinnaman]

I have a chimney top damper that works pretty well. When I'm not using the fireplace for a few days I plug the bottom of the flue with a homemade chimney balloon. I got a short length of plastic tubing, slipped one of those thick kiddie punch balloons over the tubing and taped on tight with electrical tape, then slipped a trash bag over the balloon (to protect it from abrasion/sharp edges) and taped that on the tube with electrical tape. Stick the trash bag covered balloon in place just above the firebox, blow through the open end of the plastic tubing to inflate the balloon inside the trash bag until it is snug in place. Then I stick a wire nut in the open end of the tube to hold the air in the balloon.

Works great, costs less than $5, and takes 2 minutes to install, 30 seconds to take out.

Dave

 

[Shari]

I have a chimney top damper that works pretty well. When I'm not using the fireplace for a few days I plug the bottom of the flue with a homemade chimney balloon. I got a short length of plastic tubing, slipped one of those thick kiddie punch balloons over the tubing and taped on tight with electrical tape, then slipped a trash bag over the balloon (to protect it from abrasion/sharp edges) and taped that on the tube with electrical tape. Stick the trash bag covered balloon in place just above the firebox, blow through the open end of the plastic tubing to inflate the balloon inside the trash bag until it is snug in place. Then I stick a wire nut in the open end of the tube to hold the air in the balloon.

Works great, costs less than $5, and takes 2 minutes to install, 30 seconds to take out.

Dave

Dave,

I've got to see this! Can you post a photo?

Shari

 

[Cinnaman]

Here you go Shari.....



Dave

 

[Shari]

Dave,

Now that is innovative! You have to patent that and give it a nifty name!

Shari

 

[Cinnaman]

Ha! Yeah......."Dave's Hot Air".......

I refused to pay $50 or more for the same thing I made for less than $5.

 

[TreePapa]

Build a plywood block off (only for when the FP is not in use, of course) a few inches larger than the FP opening. Put foam weather stripping around the edges (on the inside). Paint it to look like a fire in the fireplace. Hold it in place w/ a couple of heavy cinder blocks.

Peace,
- Sequoia