Replacing large furnace with wood stoves only (?)

[dave11]

Hi. You folks seem to know the score on all this, so I'd like to ask your collective opinions. Last year I bought a 58 year old house outside Pittsburgh, which still has it's original gas furnace, rated at 180,000 BTU input, and about 70% (!) efficient. I knew of course it would have to go, but in the meantime, I've been considering my options. Heating with wood though has caught my interest, for the same reasons people here already know. The house is a ranch style with 1900 SF on the main floor, plus a large walkout basement and garage underneath that are not officially heated. I'm attaching a floor plan to this post.

My expectation would be, given the floor plan, that a single wood stove in the LR would not be enough. The hallway leading to the bedrooms and bathrooms is perhaps 30 feet, with the two bathrooms at the tail end. So I'm thinking that a smaller stove might need to be placed in say, the Master?

A heat calc for this house at design temp yields between 32,000 and 38,000 BTU/H, depending on whether or not I insulate over the basement areas with at least R5. The ceilings are all 8 foot, with R30, and R15 in the walls.

The current furnace and it's ducts need to go, as they take up a huge amount of space, and the ducts are in the backwards "old style" anyway. So when I'm done there will be no heating system left. I'm assuming though that even if I put in wood stoves, that a secondary heating system is needed as well, to make up for the coldest days, and for when i'm away from home?

Thanks for any advice.

 

[Todd]

I believe it's against code to have a wood stove in a bedroom. I see you have a fireplace? Are you looking at a fireplace wood stove insert for it? If so get a large one with a blower to help circulate the heat. You may have to play with fans to get heat into those far bedrooms, maybe a box fan on the floor in your foyer directed towards the stove will suck the cold air from the bedrooms and the warm air replace it.

Another option since your taring out the old furnace and ducting is to look into a wood/electric furnace. Check out these EPA certified furnaces. www.psg-distribution.com

 

[begreen]

As you've noted, there's lots of room for improvement. It sounds like you are taking the right approach. You might consider going with a zoned, gas fired (or wood/gas), hot water system instead of forced air if you are starting off from scratch and air conditioning is separate or window units. It's good to have a backup system for sure. People get sick, go on vacations, or just want to get away for a weekend. So do have a good central system for backup, especially for when it gets very cold.

It will be a challenge to keep the bedrooms cozy with wood heat, especially the master bedroom. But the core of the house shouldn't be a big deal assuming the house is not a leaky sieve. Is the basement finished and insulated or not? What are the thoughts for heat there (or not)?

 

[dave11]

I was unaware of the Code issue, but that's probably true here in PA, where most things are regulated.

Yes, there's an oversized FP in the LR which I have sealed temporarily with plexiglass, as it was losing a ton of air otherwise. I wasn't planning to use it though because of all the negatives about FP inserts that I've heard. Do I have that wrong?

I actually am considering a hot water system, boiler and radiators, for a number of practical reasons to do with the house. I guess I was willing to reconsider this plan because it seemed some folks here can heat with only wood. But I guess they still have a backup heat source in place.

The basement is unfinished, but I was planning to put a large workshop there, which would need heat to a certain degree. Would that somehow change the heating plan for the living area, as far as wood was concerned?

BTW--electric is fairly high here, about 13 cents per kWh, so we try to stick with NG, over oil or electric.

Thanks again.

 

[begreen]

I don't have a fondness for exterior chimneys, but with an insulated liner and blockoff plate you can make this one work. There is the option of putting a freestanding stove on the hearth in front of the current fireplace to increase heating efficiency.

The reason I asked about the basement is insulation. If the walls are raw, this is a good opportunity to seal the sill up tight, then deal with the wall insulation. That can help keep floors warm and reduce heating load.

You might want to drop over to the boiler room forum here and discuss putting in a hybrid gas/wood boiler system. My brother-in-law has a hybrid oil/wood system and has used it for years. It works well.

 

[dave11]

I see your point about the basement insulation. The rim joists and sills are all open with easy access, and it was my intention to airseal and insulate them before this winter. I will insulate the basement walls as well with fiberglass, though the slab will always lose a lot of heat, so I was toying with just insulating the basement ceiling instead.

BTW--there is an equally large FP in the basement, below the one in the living room. Does that create any opportunity?

The combo NG/wood boiler is a great suggestion. I will definitely look into that before finalizing the plans for the hot water system.

Thanks again.

 

[BrotherBart]

With free standing stoves with a blower in fireplaces you can generate and move a bunch of heat and not have to build new chimneys and give up precious floor space.

Our backup for when we are away is DeLonghi oil filled radiator space heaters in each room of the house. Unobtrusive little suckers. Tried it out for a trip the first week in April and it worked great and didn't dent the electric bill all that much. Of course I was able to buy a trailer load of them for $17 apiece last year when Lowe's was closing out heaters.