Joined a few days ago - hello from Finland!

[upnorthandpersonal]

New to the forum, but not new to off-grid stuff. I'm currently building my dream place here in Finland, my log house:



Off grid of course, but providing all the modern amenities my family would expect. Solar for power, own waste water treatment (slightly more than your typical septic system), own water well, etc. Since we're in a cold climate, there are quite a few challenges to overcome. For power, sunlight isn't available from November through January. A vegetable oil generator will pick up the slack during those times. Heating is done with wood (plenty of that around), and processed with electric tools using the excess solar generated in summer. I have a build gallery with more details (at least, the first three parts) with hopefully more to come, time permitting:

https://imgur.com/a/htCRrKi

https://imgur.com/a/5VrKTBH

https://imgur.com/a/SKgNw02

 

[Bob142]

Your house and location look stunning. What an epic project. Thanks for sharing.

 

[upnorthandpersonal]

Thank you! I hope to be able to document the entire set-up; it's been in planning for a decade

 

[Steve_S]

Welcome !
Great Location and excellent design, love it. I'm also deep in the woods (Cedar & various pines) with a hyper efficient cabin, composting toilet & grey water systems, deep well (80m deep) and off-grid of course. I sided my place with Live Edge Cedar using the rainscreen method and my roof uses a Cool Roof design that provides a passive airflow and thermal break between the roof structure & roof skin, which saves huge on heating & cooling. The roof system greatly exceeded expectations & performance here in Mid-Northern Canada (see temp swings from -35C to 40C). All built by M.M.I. (Me, Myself & I)

Spoiler: Cool Roof info for the curious

Here is some info on this system from a contractor who documented it extremely well. I have slight mods for my climate but 98% similar.

Houstoncoolmetalroofs.com Is For Sale

The domain name Houstoncoolmetalroofs.com is for sale. Call BuyDomains at 844-896-7299 to get a price quote and get your business online today!

www.houstoncoolmetalroofs.com

 

[upnorthandpersonal]

@Steve_S : Interesting, seems quite similar to my roof design (including passive airflow), except I don't have the attic space.

https://imgur.com/P2hhFsJ

 

[Steve_S]

I have a Cathedral Ceiling throughout so there is no attic. BUT I do have 8" / 20cm of PolyISO insulation between the rafters and my walls are built like SIPS with 5.25" / 13.5cm High Density EPS-II foam sitting on a frost protected slab foundation with Radiant Pex heating in it. Quite comfy for an old decrepit bugger like me. Because of my build method, all windows & doors are installed into the walls with a Bailey Box system which provides me with nice deep window sills. Also because I wanted to keep the envelope as solid as possible, my wring & plumbing does not breach any of the outer walls, it's surface mounted (but you'd never know it) and the internal wall do have powerlines etc inside them. One of the difference I did on the Cool Roof design, is I put in a 3" / 7c,m slot running along the bottom of the eaves and with a venting ridge cap, the convective air flow is incredible and as that is tied into the 2" / 5cm air space between the house shell and siding skin, there is never any humidity or "locked dead air" which provides an amazing thermal break that works I both summer & winter.

Here's a pic just as I was finishing the siding (Live Edge white cedar) an the setup you see is for the porch. (roof is 12" / 30cm thick)

 

[Dzl]

Beautiful looking home in a beautiful looking place! I'd love to see your country some day.

It looks like the Finnish government has done a great job raking the forest around your cabin as well! ?

 

[Sojourner1]

It looks like a beautiful place and beautiful home in progress!?

 

[upnorthandpersonal]

@Steve_S very nice! I designed my roof in such a way that I had 40 cm to fill with cellulose insulation. The windows are all triple pane with argon gas and the floor is insulated with 30 cm or so of foam and is 'floating', with that I mean the concrete is not touching any of the walls - probably similar as yours, and also has the radiant pipes in it. The walls are laminated log 203mm (8 inch), quite massive but in essence that's the weak point when it comes to pure R value - but I accept that - I wanted a log house. I can always insulate the walls in the future, but the energy envelope as it is right now is perfectly fine and complies with some of the stricter norms for building here (even though in essence I didn't have to follow those rules).

@Dzl The president was a little behind on that, we use vacuum cleaners these days

@Sojourner1 Thanks!

 

[Steve_S]

@Steve_S very nice! I designed my roof in such a way that I had 40 cm to fill with cellulose insulation. The windows are all triple pane with argon gas and the floor is insulated with 30 cm or so of foam and is 'floating', with that I mean the concrete is not touching any of the walls - probably similar as yours, and also has the radiant pipes in it. The walls are laminated log 203mm (8 inch), quite massive but in essence that's the weak point when it comes to pure R value - but I accept that - I wanted a log house. I can always insulate the walls in the future, but the energy envelope as it is right now is perfectly fine and complies with some of the stricter norms for building here (even though in essence I didn't have to follow those rules).

@Dzl The president was a little behind on that, we use vacuum cleaners these days

@Sojourner1 Thanks!

Prior to building this home, I investigated using SIPS (Structural Insulated Panels) as well as many other methods including straw bale. I was leaning very heavily towards a Cordwood Structure which is quite common in my area with some examples dating back 200 years still in use today, even a couple of barns ! But it did not fit my timeline and a few other factors. The #2 consideration was a Butt & Pass log building but again that raised other issues. Mostly because I designed & built everything myself and as a single geezer building a home with only 2 hands & a full set of DeWalt Cordless power tools I had to consider the how-to. The only thing contracted out was the concrete pour and having the roof finshed (intsalling the metal). One thing I quickly realized & understood about LOG / Coordwood (moreso) is that the Thermal Mass of the wood itself overcomes the R Value limits. At least with Coordwood you have walls which are 12-24" thick (30-60cm) which is substantial to say the least (and a lot of labour).

My slab is identical to the image below but I used 4" / 10cm XPS foam under the entire slab, as opposed to the code minimum of 2"/5cm, which provides an R20 protective layer and my "wings" extend out 24" / 60cm from the side of the structure, to prevent frost creep

.

TIP for anyone looking at foam insulations. The thickest you can buy in Big Box stores is 2" / 5cm and whether it is ISO, XPS, EPS it's outrageously expensive (thanks to at least 500% markup, some even more) I discovered that Commercial Roofer's use much thick foams and here by law, they have to remove & recycle all foams when redoing any commercial roofs if they are not reinstalling it. This creates a chain of good high quality serviceable insulation which will not break the bank. case in point: 4'x8'x4" PolyISO cost me $8 & 4'x8'x3.5" was $7. The HD-EPS 4'x4'x5-1/2" was $10 and the XPS 2'x4'x4" was also $10 per sheet cost from commercial roofer. 4'x8'x2" ISO at Home Depot = $50 here ! Had I not gotten this deal an lucked in, I would have ended up using pure RockWool (Roxul Plus) and even that would have cost me more. IF your building yourself, do your research, nothing wrong with perfectly good recycled foam insulations, other than keeping profits out of the greedies pockets.

 

[Mark.Jackson]

Happy New Year!

 

[upnorthandpersonal]

@Steve_S cool My foundation including different gravel for drainage etc. looks like this:

https://imgur.com/a/bUTa2vA

Labels were in Finnish, but essentially an isolated floor with the heating tubes in, and a bunch of foam under it. Looks very similar to yours; guess that's cold climate best practices at work!

 

[Steve_S]

Yes indeed, in our climate where temps can go from 40C in a heatwave to -35C or lower in the depths of winter, many hard lessons have been learned and frost is the evil monster we do know.

 

[kimsv]

Great house! Nice to see some off grid projects from this part of the world. Where in Finland is this? How is your solar setup going to be?

 

[upnorthandpersonal]

Thanks! It's in Korsnäs (Pohjanmaa). Solar is 10kW of panels coupled to a 30kWh battery. As you can imagine, this gives tons of excess power in summer, but that's when I use the power to process wood for winter (sawing, splitting, etc. all on electric). Additional excess solar also goes into a 3000L hot water tank. There are actually only three problematic months (November, December and January) where we don't have enough sunlight; those are offset with a SVO (vegetable oil) generator. And the key of course is to use as little electricity as possible, for example cooking is done in summer on induction, but in winter on gas (it's the only thing I made a concession on since gas is just the best for cooking Heating is done using wood (both a masonry fireplace and underfloor heating), and in case of an emergency, there is a gas backup heater on the premise that can be hooked up to the gas bottles used for cooking.

 

[kimsv]

Wow! That’s a big battery, what type of battery setup do you have? Voltage and SCC? Interesting that is works so well in Korsnäs, I’m from Örnsköldsvik originally so that’s just across the water, can’t be more than 150km. I live further west now but basically on the same latitude.

 

[upnorthandpersonal]

Yeah, it's pretty big - 48V battery system, with 2x Victron SmartSolar MPPT 250/100. Solar panels at ~180V open circuit, 2 chains of 5kW. It's a bit of a mess right now though since this system is being renewed/optimised/changed for this new place and used to be at another place with a bunch of different components etc. The goal for this year is to finish the whole thing properly. Hopefully I'll have time to document everything and share. But yeah, solar works great at this latitude - the fact it doesn't get too hot even in summer means the panels are pretty efficient, and even in Winter there tends to be a lot of light (some reflected on the snow/ice) that generates a non-insignificant amount of power, it's just the amount of hours is limiting. But worst case scenario running only the essentials gives me 7 days of autonomy (if you design a system to be off-grid, every Watt is accounted for and non-essentials ave alternatives), and then the generator will be used to just charge the batteries over a day every week.

 

[kimsv]

Smart! Looking forward to follow along!

 

[jmicaelk]

Thanks for sharing, sounds like I could learn a lot from your system and house builds for my planed house for northern Sweden. Did I read it correct that you have underfloor heating through wood fire ?? Could you share some of that with me and how is the 3000L tank used ?? I am planing on using wind turbines for the days without sun, but that makes the system much more complex as I can not use a Hybrid inverter with built in MPPT charge controller if I understand everything correct. Anything you can share would be great

 

[upnorthandpersonal]

I didn't want to use wind since it's complex, needs too much maintenance, and too noisy. I know, a generator is noisy as well, but it's inside in an insulated technical building and it only needs to run a few days a month at worst in winter time.

The underfloor heating is hydronic, i.e., hot water is pumped through pipes embedded in the concrete floor. To heat the water, you have a thermal battery which is a 3000L water tank, which is coupled to a wood burner which can also take wood pellets if needed. Excess PV solar is also put into the tank, it's just hooked up to another heating element in the tank and switches to that when the battery is full.

The key aspect of making off grid electric work up in the north here is to limit your use of power for things that have clear alternatives. Heating is one of those: I don't use anything that needs electricity for heating, safe for an emergency battery heating pad. Cooking in summer as I mentioned I can do electric because of excess solar, but use gas the rest of the year. The rest of the heating is done using wood, as I mentioned, both for underfloor heating and this type of masonry stove. The stove keeps radiating its warmth over 36 hours, and more so with the thermal mass in the floor.