Heating options
I’m curious if anyone may have heating options or suggestions that I should look into for a house I currently live in. The house is located in NH. Right now the house has r19 fiberglass for walls and has r30 cathedral ceilings. Currently the house has forced hot air and a wood stove for heating. With the current set up the would stove is constantly going. Seems to heat the house better then the forced hot air. When just the forced hot air is running the house feels cold and drafty.
At this time I would say the envelope of the house is poor (Lots of air leaks). Something I am slowly working on. I am currently in the process of re-roofing with foam which once the project is complete will give a tighter roof and a total r value of 60. As certain rooms are redone I’ve replaced the r19 fiberglass with r23 rockwool and have tried to tighten areas that are prone to leaking. Maybe one day I will consider adding adequate foam outside of the wall sheathing if residing is done but I am pretty far from doing that at this time.
I am curious about different heating options other then forced hot air or better ways to have the forced hot air installed. My issues with the forced hot air are:
1) doesn’t seem to warm the house well with tall cathedral ceilings
2) the house is long and there is only one zone. So with the wood stove running it makes one side of the house warm and the other cold
3) basement is a walkout basement which can be finished but the ductwork from the forced hot air limits head space. This is especially true as I would like to put insulation over the slab when finishing the basement as currently the slab is uninsulated.
Anyone have any suggestions for heating options I should look into?
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Replies
Blower directed air sealing will have a greater effect on comfort than insulation upgrades.
Verify room-to-room pressure balance with the furnace running. Also review register throw (which effects mixing and stratification).
You could zone your furnace, but you must maintain proper airflow and balance.
IMO, much of "wood stove is more comfortable" is caused by the temperature being higher - which is always an option with a furnace.
Comfort issues with tall ceilings are usually because of air leaks and oversized HVAC. Fixing the air leaks will go a long way.
If you are getting new mechanicals, make sure to do load calc based on the insulation upgrades and size accordingly. Getting the right sized HVAC in there will also make a bid difference in comfort.
Shape of the house mostly matters if you have very large west facing windows and big solar gain difference between rooms. In that case a zoned solution is best.
Basement is a good place for ducting. If you don't want to loose headroom, run the supply and return trunks along one of the outside walls and the ducting to the rooms inside the floor joists. If you have windows on that wall, the ducting can be run bellow it and turn it into an alcove. This type of setup is common around here as it keeps the basement ceiling high.
Wood stoves are radiant heat sources which tend to give that “cozy” feeling. You don’t get that effect with forced air.
If you have high ceilings, you may find that the air up high is noticeably warmer than the air nearer the floor. If this is the case, a ceiling fan on a low speed to stir the air may help. Another option may be to locate your forced air systems air return vents on on the wall to draw in warm air, and close the supply vents in the room with the wood stove. The forced air system can now be run in fan-only mode to help move the warmer air around the house to equalize the temperature. There is no guarantee that the woodstove can produce enough heat to heat your entire house this way though.
I agree with the other posters about blower door directed air sealing. Fixing air leaks can make a BIG difference. Going from R30 to R60 in the roof is a big jump that should help too.
An easy first thing to check is to see if you have any leaky seals around any operable windows or doors. Those are classic air leak spots and they’re easy to fix. Rope caulk works well on windows if you just need something to last over the winter until you can fix it the “right way” in the spring.
Bill
Wood stoves and central furnace/air handlers do not play well together. If you want to stay with the woodstove, look at a boiler with small room fan coils, small zones and a buffer tank. Easy to manage heat in the areas not warmed by the stove.
When you run your wood stove, turn the fan on for your hot air system and circulate the heat.....you could get inventive and hook up a separate thermostat to do it automatically.....
This does not always work. The air is not warm enough to make a difference and can upset the natural convection currents. This has been my experience in a similar situation.
Really, forced convection over rides natural convection......