We are thinking of building a small cabin for weekend getaways and the possible week here or there. The property is located in central Indiana.

We are not 100% certain on size or details but we think we will be going in this direction:

Footprint 24' X 24'

Basement ICF (block size??)

SIP enclosed timber frame (6" walls and 10" roof)

During occupancy, heating will be provided by a small wood burner, however I am uncertain how to maintain minimal heat to avoid freezing temps. This is budget minded and I do not think the small structure warrants forced air.

I was thinking or radiant in the basement slab fueled by a small on demand hot water heater.

I guess I could better design the plumbing for easy drainage and not worry about heating when we are not there.

Ian.

Sounds like you're doing the right thing with the shell. keep plumbing out of exterior walls. If you don't have too much glass or use window quilts, I bet freezing won't be an issue. The water heater may be a good idea. Also look at electric radiant mats which go under tile in the bathroom - simple and efficient. With a good shell, the btu's that you put into the house from whatever source should stick around for a while.
_bob swinburne
www.swinburnearchitect.com

You really have three main options.

Use electric heat to keep the whole structure above freezing. You could either recirculate hot water through the slab, or just use electric resistance heat. If you are planning on using wood heat when you are there, a simple electric heater will be much cheaper, also if the power goes out during a winter storm, the pipes could bust up under the slab, which would be a nightmare.

Use resistance heat wires directly on the pipes on a timer, with all the pipes insulated outside of the wires. That way, you could heat only the pipes to keep them above freezing. My parents use a system like this where they work. Still, if the power went out, you would be in trouble.

Being able to completely drain the whole system would be the best method. Even if you decide to use on of these other methods, adding a few drains to be able to drain the system if you have to drain it will still be a good idea.

Alot of people drain their plumbing. The best way to go, especially since you are building new is to design your layout around a wet wall perpindicular to an exterior wall where your well or water line comes into the basement. Have your kitchen and bath plumbing back to back. In the basement frame a small utility room below your plumbing wall, insulate the whole area and use a small electric heater, not a cheap milkhouse heater, to heat the room and keep your pipes from freezing. When your gone shut the water off and open the faucets, flush the toilet empty and put some rv antifreeze in the bowl and main floor traps. Keep this heater on a seperate thermostat.

Although it started out as something quite different, we ended up with a very comfortable cabin that is quite energy efficient for around $30,000.

We started by building a 30x36 Morton building.  This is a 'pole barn' with metal siding and metal roofing.  The walls are supported by 6" posts every 6 feet (I think; might have been 8').  Roof is supported by prefab trusses.  We prepared a pad with local rock, and the barn went up in a day.  They came back the next day and poured the concrete slab inside the barn.  The original intention was to use this to store our camper and other toys while we built a house on the land.  When we decided to wait a few years on the house we started to do some finishing of the barn.

I built 2x4 interior walls between the structural posts.  This left a gap on the back side between my wall studs and the exterior wall stringers and siding.  We hung 6" fiberglass batts in the wall and let the glass fluff out into the gap. After wiring, drywall went up.  We built an internal wall to separate one garage bay from the living area.

For the ceiling I used joist hangers to hang 2x6 rafters between the trusses.  We hung drywall then blew 48 bags of cellulose into the attic.

Because we were worried about freezing in the winter, all of the water is contained in the bathroom and the pump room.  The interior walls were insulated around these two rooms, and we intended to heat them with small electric heaters during freezing weather.  Because I didn't want to dig up the concrete, we built the bathroom up off the concrete slab.  Because the barn has 10' ceilings, there's still plenty of headroom in the bath, and the pipes run under the raised floor.

For primary heat we installed a wood stove.  We tend to leave a window open when heating with wood, because to get the stove hot enough to burn efficiently, raises the temp inside to uncomfortably warm levels.  Interestingly enough, the main room of the cabin has never gone below 35 degrees (F) in over 5 years, even without ANY heat.  We're located in central Missouri, and we've had below-zero temps for prolonged periods.  I believe the earth beneath the slab is warm enough to keep the main room above 32 even in the coldest weather.

In the summer we can open the garage door for summer breezes.  We purchased a screen that covers the entire door opening.

The Morton building and slab was around $19,000.  I did all of the finish work (except drywall) myself.  Excluding the underground electric service, well and septic tank, finish work was less than $10,000.  We ended up with a very comfortable, zero-maintenance cabin.

Rick

Thanks for the replies.

Over thanksgiving weekend, we are going to have some contractors come to look at the land and give us some estimates for the laneway, basement (if we decided) ,septic and well.

I'm sure it varies by local, but what is the general rule for electrical hook-up to the house. How far off the road would the utility typically run the wire vs. us having to pay? I estimate the laneway to be about 1600 feet long.

I wondered too about how hot the place would get even with the smallest of wood burning stoves. This seems to be the smallest that I have found. Says will heat up to 600 square feet. I think it would heat the 24' X 24' space quite nicely.

http://www.vermontcastings.com/content/products/productdetails.cfm?id=135

So we looked more closely at the site and a basement does not really seem to make much sense.

Options would be slab on grade or possibly piers.

From an initial as well as long term cost which would be better?

Insulated slab or insulated joist / subfloor?

Other advantages? (flexibility with plumbing with floor on piers for example.)

Thanks again!

Ian.

Thickened edge monoslab will be cheaper, and will provide a good stable floor IF you will put some rebar in it. If you don't see the need in rebar, do yourself a favor and use joist and subfloor.

Another good thing about concrete, is you can have it stained or polished, and presto you have a finished floor surface.

In my experience, even a small fire can make a large house uncomfortably warm. With the size of room you are referring to, be ready to open windows or that fire will run you out of there. If you use a slab, you can insulate the bottom and edges, and the slab will act as thermal mass. It will store the excess heat you will have when the fire is roaring, and re release it once the fire goes out, evening out the temperature swings.

Yes, it is harder to fix plumbing mistakes, but double checking your measurements can fix that. You can use some of the money you will save by using the slab to slightly oversize the drains to keep them from clogging. Also, include some cleanouts where you can.

Ian,
We have a 24x28 2 bdrm 1 bath cabin in northern minnesota on piers with a wall furnace with blower centrally located that will heat the place up in freezing temps no problem.

With point loads in a timber frame you might end up with big piers and or complicated beam framing depending on design, I think grade beams would be easier. I have another property that has a wall furnace with no blower that heats the entire unit, 672 sq ft, year round. They're both Empire wall furnaces in the 40,000 btu range. I think its a great solution as you can locate your thermostat near plumbing and not worry about freezing pipes and not dink with wood. Wood is a novel idea at first but becomes a giant pain in the ass unless you like spending your vacation time hauling, splitting, stacking and then hauling it into your house again. Better as back up heat.

Little furry mammals will have a better shot at getting into your cabin on piers as well, and you need to be high enough off the ground to avoid using pressure treated lumber, on the other hand I like the look of a cabin on piers latticed off versus slab on grade which looks reminds me of hud housing or something. If you have year round plumbing and freezing temps you will need to create an insulated "room" for the water line and drain line to avoid freezing.

If you do piers make sure they are designed correctly with footings underneath otherwise your little cabin can fall over as frost heaves it around (if your winters are severe)