I am in the process of buying a unique post and beam log cabin. This cabin features 30′ high ceilings and a metal fireplace right in the center that can raise and lower. My first problem is there is no heating or air-conditioning. I live in Southern Indiana. My thoughts are using mini splits. This is an all open structure with cathedral ceilings. Everything is pretty much exposed so hiding anything would be a chore. It has two separate lofts on each side. This is an all open structure. I will be sectioning two rooms off on one side of the loft. The other side already has a room and a bathroom. Thanks for the help!
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Minisplits are a great way to heat and cool living space, so that's a great option. Out of curiosity, how did the previous owners heat and cool the space?
Do the cathedral ceilings have any insulation? The reason I ask that question is that a well insulated ceiling would require a smaller BTU minisplit set up than an uninsulated or poorly insulated cathedral ceiling... And if the roof needs attention, rigid foam could be added to the outside of the cabin to better insulate the building.
I live in a log cabin, and I've tightened up with air sealing the inside with chinking and the outside with caulking. (Sashco products designed for log homes...)
In looking at your picture, I was wondering if you could hide the minisplit line sets in fake roof rafters alongside the wall in the loft. If you built a hollow beam to match your existing roof rafters, it might be an easy way to hide the linesets and make the installation more attractive.
Also, for the rooms you are building insulate the partitions for thermal benefits as well as noise transmission reduction. I did this in my log cabin when it was originally built, and it makes a big difference. If your new rooms are not "full height" in the loft, insulate the room ceilings too. (I really like mineral wool insulation, as it's easy to install, stays put, is mold and moisture resistant, and the critters hate it. Mice, for example, love nesting in fiberglass...)
A final thought is regarding the use of the cabin. Will it be your full-time home, or a weekend or summer home? Would it make sense to just heat and cool the smaller rooms, or would you need to condition all the floorspace throughout the cabin?
Good luck with your new place! It sounds like you'll have a lot of fun renovating and improving the cabin, and that fireplace that goes up and down is truly unique!
The previous owner just had fans for cooling and the furnace just lays down flat. It blows out the bottom of the unit and all electric. There is a air conditioner unit outside but the line sets were never hooked up. Thought about just selling that unit. I have inspected the roof and it appears to have 1/2" of just regular house foam for insulation. When I decide to replace the roof the rigid insulation will be a must. How thick did you go? I will have a ton of air sealing to do. The chinking does not look very good. Not sure if they used the right product. A lot of it looks loose. Thanks for your help
I don't have a cathedral ceiling in my log cabin, and there are a number of ways to have a well insulated cathedral ceiling. (None are quick and easy...) I'll point you to an article by Martin Holliday entitled "Five Cathedral Ceilings That Work" for some ideas, but another option would be sufficient thickness of Rigid Rockwool insulation to meet or exceed your local code. In the Fine Homebuilding 2021 home build in Nebraska, they used a Rockwool product on a low-slope roof...
For chinking, I used Sashco's Log Jam, inside the house. It comes in a variety of colors and you can buy it in large caulking tubes (30 oz.) or in bulk. For caulking seams outside the house, I used Sashco's Log Builder. I use a cordless caulk gun, and it works well if you have one person running the caulk gun, and another smoothing it with a brick jointer tool. A mix of water and rubbing alcohol in a spray bottle helps with tooling the chinking and caulk...
For larger air leaks, use spray foam. If you don't have a spray foam gun, get one, and don't depend on spray foam cans that come with a straw. I always used the "straw cans" until about a year ago, but once you've used a gun (~$50), you'll never use the "straw cans" again.
If you need to refinish the exterior, remove existing stain with a wood-friendly product like CPR, and treat the logs with a borate product such as Penetreat to keep the wood-eating insects from being attracted to your logs, before restaining/refinishing. (I use Penetreat to treat non-PT lumber to make it last outdoors by spraying or dunking, and I've had great success with Douglas Fir that looks great after a number of years...)
You might want to start with some kind of manual J analysis to get your arms around the heating and cooling load.
the photo looks like this is built like an old school ski lodge. build a fire big enough, it is good for folks to warm up from being in the cold.
options for insulation are many. but the first step is to size the heating and AC loads.
good luck.
I have had several HVAC guys there to give me there ideas. I like the Mitsubishi units but that contractors quote was $25k. The fijitsu mini split quote was better at $15k. Still wanting to get a few more quotes to figure out the best method.
Are there any rebates from your local utility for minisplits? Where I live in NY, the local utility, Central Hudson, covers 1/2 the cost. My daughter had Mitsubishi mini-splits installed for about $20K, and their net cost was about $10K. I don't think you can go wrong with either Mitsubishi or Fujitsu, but carefully compare the proposals for the workscope they are including and the details of the installation. Usually, the installations are for their ease of installation, and not for aesthetics...
The place looks inviting and welcome but the big open plan that makes for great aesthetics is going to rub up against the realities of HVAC. If you insulate you lose all of the exposed framing that make the place look great. If you do outside insulation you are looking at tons of work.
There is no magic bullet here. Do your research and let us know what you plan to do. This forum is not going to figure this out for you but if you come back and post solutions you might help many others.
Thanks. I thought so as well. It sits right along a creek in the back. I am going to document everything I do on this project and going to post the knowledge I learn.