As much as I would love the space where the oil tank is, it's not worth spending 9-10K just to get rid of the oil tank. Considering the slim margins any savings may bring, I don't think it's worth it. Especially since my boiler is on the younger side and is in perfect working condition. If my boiler was old, inefficient, and on its way out, then a conversion would make more sense. I think Dana makes a ton of sense in trying to make sure my house isn't leaky b/c plugging up any potential leaks will save more in heating costs.
If I can share one of the pictures you showed me in the message board, those "...potential leaks..." and the conductive losses from the uninsulated foundation are potentially quite large:
Notice that none of the seams in the doubled-up framing are caulked, nor is the seam between the mudsill/bottom plate and the foundation, with only partial and
wretchedly installed insulation on the framed part of the wall, with no interior side air barriers on the studwall to boot.
WAG: Even without actively heating the basement, the
basement air leak & heat leaks alone are likely to be north of 15% of the total oil bill, and can probably be fixed (or at least mostly fixed) for less than $10K, less than $5K if taken on as a DIY project.
Some primers on the
topic live
here. I've also covered the topic of
air sealing & insulating basements (using methods that don't create mold farms) in some detail
multiple times on the
TerryLove forums too. (There are many more.) Combined with the other air leaks and insulation gaps in the house it's probably cost effective at current energy costs to bring the net heating load down by 25-30%.
Since part of this basement is finished with fiberglass studwalls up against or near the foundation walls it may be harder to get at some of the air leaks, but based on the construction in the laundry area this is typical leaky pre-1990s construction.
Current code minimums for basements in NY are R10 continuous insulation (or a 2x4/R13 studwall) from the slab all the way up to the subfloor for the first floor. (See the values for the Zone 4 row of TABLE N1102.1.2). But for the insulated studwall to meet that performance level there needs to be well sealed air barriers on all sides of the batts. From a moisture control point of view studwalls that extend below grade are risky. In IECC zone 4 (Long Island, NYC, & Westchester County) it's best to have at least an inch of insulated foam board between the studs & cavity insulation and the cold damp foundation. That limits the rate of groundwater moisture entering the studwall portion, and prevents wintertime moisture accumulation which would otherwise accumulate in the fiberglass where the foundation is above grade.
I won't go into all of the details on basement insulation here unless prompted, since it's way off topic for the HVAC forum. But given the construction of the house the conversion money is far better spent fixing the air leakage and insulation gaps in the house, not limited to just the obvious deficiencies in the basement.
It doesn't hurt resale value of the house b/c there's already gas in the house. It would be easy for any prospective buyer to convert from oil to gas heating in this house if they chose to go that route.
That's true. If you're keeping it for another 10 years heating with EITHER gas or oil is likely to be a net-negative. New York's current greenhouse gas emissions goals are more ambitious than the national average, but hardly very ambitious at all, and that's likely to change. Even at the federal level there are now serious discussions of a carbon tax (which would make both oil and gas more expensive) and net-zero greenhouse gas emissions (all sectors, not just power generators) by 2035. You can't really get there while still burning oil or gas at home.
Making the house more efficient is step 1. When policy incentives (both carrots & sticks) make it worthwhile, having a lower-load home and developing the plan on how to heat & cool it cheaply without on-site combustion is really more prudent place to spend the money.
FWIW: When I first moved in to my own 1920s antique ~2400' (+ ~1600' of full basement) 1.5 story bungalow the design heating load was about 50,000 BTU/hr (@ +5F) the cooling load was about 3 tons (@ 83F) , and the comfort levels were pretty low during cold snaps & heat waves, the indoor air was Gobi-desert dry in winter, tropical in summer. The walls and attic were only partially insulated, foundation walls completely uninsulated, and the place leaked air like a tennis racquet. By spot insulating & air sealing behind the kneewall attics, blowing cellulose into the first floor walls, and DIY-ing R15-R20 worth of rigid foam on the foundation walls brought the design heat load to about 35-38K, the design cooling load is under 2 tons, and the indoor humidity can now be controlled by the ventilation rates.
The original boiler (since replaced by a modulating gas-burner a dozen years back) was sub optimally oversized by a bit more than 2x for the original load, and ridiculously oversized (by 3x) for the new-improved lower load. The 5 tons of central AC (on the list to be replaced) is also on the ridiculous side- we can get by most of the summer running a half-ton window shaker in the upstairs and leaving the doors open to allow the first floor to convection-cool. The all-electric plan for
this house is still in flux, largely due to the dearth of hydronic output heat pumps in the North American market, but a 4 or 5 ton LG Multi-Vs full VRF could easily handle the hot water and heating loads. There are several mono-bloc style hydronic heat pumps that could handle it too, but in my climate where -10F outdoor temps aren't super-rare using a mono-bloc would require anti-freeze and higher, less efficient water temps or more radiation to handle the lousier heat transfer characteristics when anti-freeze is in the mix. Going with a more dilute anti freeze only sufficient to prevent pipe bursting (but not prevent freezing) is one possible compromise, but I'm hoping more fully split hydronic heat pumps using more environmentally friendly refrigerants will make it to our shores.
In RJHNY1's case it would be easier. He's unhappy with the comfort performance of the existing hydronic system, and separate duct systems for (likely way-oversized) air conditioning two zones already exist. An all electric plan there would be a bit easier here than at my house, replacing the existing AC units with right-sized heat pumps (right sized for both heating & cooling at the new-improved "after upgrades" version of the house), and installing a heat pump water heater. Since the AC is fairly new and the boiler has substantial life left, just as in my case there isn't any rush to make that conversion. But if/when the boiler fails or either of the AC systems fail it's worth having the plan already in the file to avoid making yet another $5-10K mistake on equipment selection. If greenhouse gas reductions incentives or oil pricing volatility make it cost effective, it may very well become worth retiring the equipment early, getting rid of BOTH the oil tank
and the gas meter.
But the real no-brainer "right now" investment is air sealing and insulating anywhere that doesn't require gutting a nicely finished room. It might still not "pay off" on an NPV basis or immediate resale value financial basis, but it WILL pay off on a comfort basis, something that a mere fuel conversion (of equivalent or lower financial return) will NEVER do. Moving to gas won't change the deficiencies of the radiation, with the same drafts & colder or hotter rooms. Insulating and air sealing makes it possible to actually
control the heat & moisture flows in the house, and lowers the room to room temperature differences.