Post Frame GARAGE/LOFT Propane Heat?

[Shrubsteppe]

Hello All.
I am in Central WA. 2000' on side of mtn. Building a 1200 sqft workshop/garage w/ 600 sq ft LOFT studio spartment (open floor plan w/ 1ba).
I am 100% off-grid Solar + propane. Well water.
Opinions pls. on propane heating options for LOFT space. The 4 winter months avg 10 - 15° F. (Lows -10).
First I'm going to insulate the s**t out of it!
Then... Rinnai, Martin ? direct connect wall mount propane heater?
Additional Radiant floor heat set-up?
I can site all mechanicals in garage space below loft and just run up piping.
Garage will be insulated also.
Wife and I will be lliving here for 2 yrs. while I build main house. She won't commit if I can't promise her "warm" winters.

I'll have a 10Kw solar setup for the main house (which I can utilize until its built). After we move into house I just need reliable lp heating for the loft when kids visit during winter. I will have a 1000 gl lp tank (waiting for main house) I can tap into.

I'll have 2 ceiling fans to circulate heat (+ cool).

re: "insulate the s**t out of it".
as in closed cell spray 5" x r6.7/", ext sides & 1 inner wall + floor of loft., 6" roof


Appreciate ideas.

 

[jives]

Surprised no responses yet, but here is my $.02. First questions is what is to be done with the room after you move out. Garage office? Rental space? Mother-in-law apartment? In other words, how much use will the space get? Will it be occupied full time, or only on occasion when the kids come? While the mechanicals are in the garage, you still have plumbing water that needs to be kept from freezing.

If part time or sporadic use you still need to keep the space warm to prevent freezing of pipes, so what is going to be the most efficient and mindless way to keep the space at 55 deg when no one is there? Radiant? Wall mount propane? Keep in mind that the bath may not warm with a single wall mount propane in the room.

We have a dual wall-hung unit that provides both domestic hot water and radiant hydronic heating. The plumbing is complex, more so than I would want in a loft apt.

 

[jrsavoie]

Surprised no responses yet, but here is my $.02. First questions is what is to be done with the room after you move out. Garage office? Rental space? Mother-in-law apartment? In other words, how much use will the space get? Will it be occupied full time, or only on occasion when the kids come? While the mechanicals are in the garage, you still have plumbing water that needs to be kept from freezing.

If part time or sporadic use you still need to keep the space warm to prevent freezing of pipes, so what is going to be the most efficient and mindless way to keep the space at 55 deg when no one is there? Radiant? Wall mount propane? Keep in mind that the bath may not warm with a single wall mount propane in the room.

We have a dual wall-hung unit that provides both domestic hot water and radiant hydronic heating. The plumbing is complex, more so than I would want in a loft apt.

I would go with something like that if there's floor heat in the garage.

You can always install a heat exchanger for forced air for the apartment.

With the insulation you are talking about, you shouldn't need much.

The floor heat will go a long ways towards heating the whole building.

 

[Jackfre]

The Rinnai EX-22 (8200-20500 on LP) will walk away with that space. It draws between 33-56 watts.

 

[dcg9381]

direct connect wall mount propane heater?

I have a 2400 sqft building that heated/cooled by 2 ductless systems. Below 30 my particular ductless system - heat BTU capacity drops pretty rapidly.

When Texas had the "great freeze" in 2021 (and associated power outage) - I started figuring out how to heat the house and shop with propane. The house I have a 500 gallon propane tank and the shop got a 100lb propane tank. I use ventless wall mount propane heaters. I have 3 ranging from 20k - 30k BTU. I can heat the entire house from one 30k unit (3000 sqft) when I place it in the basement near the stairs.

For your deal (off grid) - highly recommend. They're cheap and work great.

 

[toyotadriver]

For a cold climate, do NOT use ventless heaters. They work ok in dry, not too cold climates (especially when you also have another source of heat) but outside of that, they introduce too much moisture to the inside. Yes they work and yes they are cheap but that’s about it. The OP should not consider them for his project.

 

[Awag]

For every gallon of propane you burn as a by product the heater puts out a gallon of water. So a ventless heater puts all that water vapor into the air. Causing rust and mold.