Retrofit from Hot Water heat to Forced Air

As mentioned in other posts, we are the new owners of a cottage that has hot water heat produced by a natural gas boiler. This was the full-time, year-round residence for the previous owners. For a host of reasons we're now considering a retrofit to a forced-air natural gas furnace.

Amongst our goals are to be able to completely shut everything off during the winter. We would drain all water, use proper, environmentally responsible anti-freeze in all traps and drains, unplug everything electrical and stay away until the snow melts.

We have another place in northern Michigan in the woods, and we shut it completely down after each use. It has not been a problem and the cabin itself, the appliances and everything else I can think of have not been hurt by this procedure. We’d like to do the same thing at the lakefront house. If we were to spend a few days there during the winter, we would perform the same shutdown after our stay concluded.

I'm interested in hearing your thoughts regarding a new heating system and the practicality of installing it myself. I am not a tinsmith, and I am not an HVAC person. However, the new flexible ductwork seems to be easy enough for a mechanical person to work with. The house is 1450 square feet and a new furnace seems reasonably priced at Home Depot, though I have not priced all of the affiliated items.

If contracted, what might we expect to pay for a professional to complete this work?

The ductwork would be placed in the attic (unless experts advise that the crawl space is preferred), and there are no known obstructions. Any thoughts? I'd really be interested to know if this is a project beyond the ability of most laypersons.

Thanks for your replies.

Didn't know you could buy furnaces at HD, except an installed package from their contractor.

There is a lot of labor, especially working in a crawl space or the attic.

If this were a primary residence, we would give you the usual lecture about doing a manual J heat load calculation, and having a very experienced HVAC contractor design the flows, the duct sizes, etc. Given your proposed usage, "winging" it will probably keep you from freezing on the occasional weekend.

Especially in cold climated, the ideal location for heat outlets is on the floor, because of the basic fact that heat rises. Here in S. California, most homes are done with heat outlets high on the wall, partly because it is cheaper ( ducts are in the attic, not crawl spaces or basements) and partly because high is better for the cooling season.

HD will give you a free estimate for the job. That would give you a starting point. This job has a lot of labor, and they will not break out the specific equipment costs, so it can be hard to compare.