Hydronic or Something Else

As they work to remove and decommission the heating oil tank, I am considering how to heat the place.

Currently, the forced air furnace distributes heated air to the main part of the house and there are two electric wall heaters for the breezeway and BR3. We can replace the oil-fired furnace with a 96% efficient Lennox EL296V gas furnace and make minor adjustments on the ducts and vents for $7,346.37 (Greenwood Heating bid, 9/1/15). We still have to (or should) insulate the 1296 SF floor.

If we go that route, we might leave the two electric wall heaters in place (or move them slightly) and install a Mitsubishi mini-split in the Trees Room (on the wall between the entry ceiling and the Trees Room ceiling) that could provide heat for the 5,600 CF high-ceiling area, and the cool air would cover the whole house on peak cooling days. Those are about $5,000.

Back on April 23, I got a bid from Northwest Mechnical of $32,470, and a better price from Radiantec for a hydronic system on May 15. They bid $4,202.50 for the tubing under the floor, $5,646.90 for a Noritz NRC1111 boiler and custom heat exchanger and three-zone manifold system, and $1,200 for (30) Sunboard Sunfoam panels for the BR3 concrete floor. The total bid was $11,049.40 not including shipping (from Vermont) or any installation.

But, wait. Real oak floors aren't great with under-floor hydronic. The spot heat might dry out individual boards, leading to joint separation and/or "cupping." We could install the hydronic and deal with floor problems as they occur, or we could proactively remove the oak flooring and put in 1300 SF of, say, ceramic tile. That's about $9,750 not including the demo and disposal of the old floor. $7.50/SF is tile or hydronic-compatible engineered wood.

So, the hydronic approach is: $11,050 materials, $250 shipping, $10,000 installation, $2000 floor demo, $9750 new floor. That's $33,050.

Noritz NRC1111--18" x 24" x 9"

To compare apples to apples, let's assume we get the Noritz boiler ($1600) for tankless water heating, refinish the oak floors ($3570), and insulate the floor and ducts ($5000).

Hydronic and new tile/engr wood floors with 3 zones: $33,050
Forced air with some a/c but only 1 zone: $22,520

The trouble with these numbers is that I have bids for the forced air, but the hydronic installation could cost even more.

Three zones is useful for apartment/Airbnb solutions, but it's not worth $10,530. The other advantage of the hydronic is the elimination of the ugly baseboard vents--hydronic heats without moving dusty air around, which is very appealing. But we could make some pretty vents for $500.

Refinishing the oak floor is based on a 3/2/15 bid from Lane Hardwood. New oak is $11.25, but refinishing is $4.75/SF. However, we're only talking about refinishing the two bedrooms, living room and hall--about 750 SF.

The forced air solution means a separate control for the Trees Room and just the electric heater for BR3. We might want a mini-split for BR3, or a second electric heater for BA3. The three baths might want electrically-heated floors with the $10,000 that we're "saving."