Adding a fireplace to an existing home
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| Posted in General Questions on
Any advise on adding a fireplace to an existing home?
We live in Climate Zone 5, and the winters get pretty chilly. We have geothermal, but it doesn’t seem to help much in the way of warming during the winter. Our heating bills were outrageous last year.
We are looking into adding a fireplace, and would like to vent out the gable end of the home, if possible.
We have a company coming out to give us a quote, but anything I should consider to mention to them? We have a metal roof, I would love to avoid making any holes through it.
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Replies
I know it bothers you to go through the roof, but I would only install a wood fireplace with a straight vent all the way up. No bends. Period. I know there are lots of fireplaces/woodstoves installed with 90 degree vents out through the wall, but I would never do it that way. Just too big a fire hazard - even if you know what you're doing with wood fires.
Also, make sure you can get insurance. In some areas it's a real problem. And they may have something to say about the way it's vented. They will definitely have several other requirements that you need to be aware of before going down that trail.
Back to your heating problem. You say your heating bills were outrageous, but the geothermal doesn't provide much heat. Do you have electric resistance baseboards as well?
We do not have electric resistance baseboards, no.
I honestly would prefer to not put the fireplace in at all, just from reading there isn't much heat gain at all.
Are they any safe, vented options out there to add a little additional heat in the dead of winter?
Check out woodheat.org for fireplace installation recommendations. It's true that open hearth fireplaces produce negligible (and sometimes even negative) heat gain. Modern fireplace inserts are better, but I personally would never use one as anything other than an occasional use / ambience appliance. Relying on it to heat your house is going to negative affect your air quality, and probably your quality of life (just try to imagine having to bring in firewood and feed the thing regularly, often at inconvenient times).
Are there areas in your home that you could improve to lower your heating load? Air sealing, extra insulation. If so, that is money better spent. If not, there are still other options besides wood heating, but we'd need some more details about your house and available energy sources.
I am having a weatherization contractor come out next month. Doing a blower door test and using infra red to identify where the leaks are at map out a plan from there. We have a fairly tight house, did a blower door before and score was 1700 for 4000 sq ft home. I think some of our problem is the cathedral ceiling. I feel like the huge family/living room is just taking too much energy to heat. That would be the main room we would like additional heat in.
I would advise you to consider electric inserts. There are no chases to build, no pipes going through the roof (less leaking potential), no carbon monoxide, gas pipes to run, no wood to chop or stove and pipes to clean... NO MESS! Most plug-in in a 110v outlet and produce a lot of radiant heat. They also look good and are big help with good indoor air quality.
We haven't installed an indoor open flame fireplace in 20 years, and started to use electric fireplaces within the last three years for all projects, even for multi-million dollar projects. Once we explain the benefits to the homeowners, there is no comparison.
https://learn.compactappliance.com/electric-fireplace-benefits/
Armando, do you feel they emit plenty of heat? My husband questioned me last time I brought these up.
There are models that heat 1,000-1,200 sf. Wood and gas fireplaces loose up to 70% of their generated heat “up in smoke” (pun intended, plus its 40 years since Cheech and Chong’s movie)… compared to electric fireplaces which have radiant heat, much more effective.
P.S. The tighter your building envelope, the more efficient they are.
A right-sized EPA rated wood stove is a real heating appliance, and doesn't need the power grid to function. It's local air pollution issues are real, but a tiny fraction of an open hearth fireplace. Unlike the fireplace, it puts out a significant amount of heat.
There are any number of them that come with big viewing-window front doors on them to give most of the dancing-flame charm. (Some better ones have a hard coat low-E coating on the fire side of the glass to keep the fire burning hot for higher efficiency/lower pollution.)
With a wood stove there are engineered insulated stove pipe kits to make installation easier. It's always better to run the stack indoors rather than going out the side and up the outside of the house, since a cold stack will be prone to backdrafting when starting.
You need some additional information before you can make a good decision.
What is the rated heating capacity (size) of your existing geothermal system? Do you have any information about the level of insulation (R-value) that was installed in your home? Ideally, you would know or calculate the heating load of your home. Do you have natural gas available?
Any contractor will need this information before they can give you a quote that is worth anything more than the paper it's written on.
Kathleen,
You need to sit down and assess what you really want. Do you really want a fireplace? (Most traditional fireplaces actually work to cool down a house when they are operating rather than warming things up.)
Or perhaps what your really want is a warm house? If so, it's important to figure out why your existing heating system can't provide adequate heating.
What some people call a "geothermal" system is more accurately called a ground-source heat pump. Many homeowners report that their ground-source heat pump systems provide disappointing performance -- due, for example, to poorly sized pumps or some type of system commissioning error. You may need to hire an experienced consultant capable of analyzing the performance of your ground-source heat pump.
It's also possible that your home simply needs envelope improvements (air sealing work and insulation upgrades).
I doubt whether the installation of a fireplace would solve your problems.
It seems to me you already have a very expensive heating system, you should get it to work. The one thing that is all but certain is HVAC contractors do not install undersize equipment.
How long have you lived in this house?
Heat pumps do take some time to get use to. They only warm the air about 15°, so even the air coming out of the register feels cool. I say pick a temperature sat your thermostat to keep that temp 24/7.
In a tight house to get smoke to go up a fireplace flue you need to open a window to allow enough air into the home to replace the air going out the flue. Often it will take more BTUs to heat the air coming in the window than the fireplace puts into the room. If you do not need to open a window that just means your house is very leaky, the same amount of air is getting into the house somehow.
Walta