One of the major projects in our remodel is replacing the heating system, and I’ve been thinking more about it recently because our house is chilly. I sometimes feel like living in our old house is actually a trip back in time, where I need to wear a house robe and slippers over layers of clothes just to fend off the cold. Our efforts to weather seal are hindered by a complete absence of insulation in the walls or ceiling.
Currently we have an inefficient old boiler with steam radiators. There are three radiators on each floor with pipes running through the basement and up through the first floor to reach the second, plus a brick chimney in the center of the house that both the boiler and the water heater share.
The challenge is that we’re remodeling in phases (first floor then second) but we have one heating system. We’re planning to replace it with a new high efficiency boiler (which will direct vent rather than need a chimney) and radiant floor heating, in our case a system of panels that install on top of the subfloor and have pex tubing run through them. In order to finish the first floor, we need to remove the chimney, pipes, and radiators from it. That means that the old heating system will no longer work but the new system would only be installed on the first floor, leaving us without heat on the second floor.
Because of this I had originally been looking at a radiant heating system that installed under the floor, so we could heat the second floor from below before we remodeled it. There are a few problems with this approach: it’s not as efficient as the above subfloor system because it has to radiate through an extra inch of (non-conductive) wood, we’re planning to replace the plank subfloor with OSB and installing the pex tubing to it would prevent us from doing that, and finally the new system will be sized for the highly-insulated walls we’ll eventually have and most likely will not be powerful enough to heat the second floor until the insulation is installed.
So, how can we heat the second floor if we can’t use the radiators and don’t yet have radiant floors? One option is the forced air system we’re planning to install for air conditioning and ventilation. We could get a furnace rather than a simple air handler and install the ductwork sooner rather than later. Because the ducts will go through the attic and basement, they won’t require significant intrusion into the second floor, just a vertical trunk that would go through our bedroom. It would also give us a supplemental way to heat in the event we ever had a problem with the radiant system. However, we still have the problem that this system, even if we wanted to install it, would most likely be sized for the eventual high levels of insulation, not our current drafty state of affairs and might not be up to the task. It’s also a large up-front expense that we were planning to put off for some time.
That brings us to the other option: space heaters. I started looking at electric baseboard and oil-filled heaters. While not a very cost effective way to heat a home, neither are our steam radiators. It’s entirely possible that running electric heaters would cost less than running the boiler, considering Chicago’s electric rate just dropped to 5.424¢/kilowatt hour and the fact we’re only heating one floor. Next, I briefly explored the option of an electric heat pump, which is much more efficient and can cool as well as heat, but it also costs ten times as much to buy and for a temporary solution it just doesn’t make sense.
In addition to the operating costs, if we got electric heaters we’d also need to run new wiring to power them, plus we would need at least three of them given they’re limited to 1,500 watts each. Once I started thinking about running three new circuits, it occurred to me that for about the same amount of effort I could run one gas line and put in a vent-free natural gas heater. A gas heater would deliver several times the heat of an electric baseboard and cost much less to operate. Best of all, while not as cheap as baseboards, they’re fairly inexpensive.
As with everything, there is a trade off. Vent-free heaters cause increased moisture in the house and can adversely affect indoor air quality. Unfortunately, the direct vent alternatives that put out the same amount of heat cost several times as much and are less efficient. Despite the concerns, vent free is safe and with the house being as drafty as it is I’m not too concerned. They have built in oxygen depletion sensors and we have a carbon monoxide detector as well.
My plan is to get one, install it, and see if it keeps the house warm and if it’s cheaper to operate. If so, we can get rid of the boiler and radiators right away. If not, we can keep using the radiators for now and only switch to the heater for the second floor when we have to remove the chimney.