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felineman
Member
# Posted: 20 Feb 2015 01:34
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Only in the planning phase, but thinking dig down 2 feet and using gravel stacked stone 2 feet wide 1 foot above ground level with drainage weeper system. Otherwise known as a shallow trench rubble foundation. this will be done in Northern Ontario in an unincorporated township. Anyone see any problems? There won't be any permits required as I will be at least 200 km from nearest town. Very little information in this type of foundation. Everyone expects you to pay thousands to have poured concrete. Stone and rocks not an issue will NOT be using mortar or cement, dry stacked only like the days of old.

OwenChristensen
Member
# Posted: 20 Feb 2015 08:27 - Edited by: OwenChristensen
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Very interesting. What dimensions?

I'm a builder and I would not expect that you wouldn't have a lot of frost heaving. Normally we need to go under the frost levels or on smaller building float on top. I have wondered why the rock pile on my old homestead seem to be so solid.

Owen

Don_P
Member
# Posted: 20 Feb 2015 08:34
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Typically the rocks shift and the bearing changes, the house settles until doors and windows bind or the floors go unacceptably out of level. I've worked on a number of these, presently putting the third foundation under one. We found and saved many of the rocks that were under there from the first foundation. The second foundation was difficult for them to install properly and they took shortcuts because the work was difficult, so it also failed.

There is nothing wrong with a proper rubble trench foundation, which is actually just a footing under some other type of foundation wall or slab. Those walls can be poured in place, precast or treated wood.

leonk
Member
# Posted: 20 Feb 2015 09:41
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welcome, fellow Ontarian Where's the place?
I am not sure at what level you're going to install the weeping, but the water has to be removed from the foundation or you will have a problem. If you dig a trench and the soil is poorly draining type, you're going to have heaving.
It has been said here before - dig below the frost line or don't bother at all. Unless you're building large structure, I wouldn't dig.
Or just remove the top soil. What kind of ground is there?
The site elevation is very important - the foundation and the water removal from around the foundation, has to be designed with elevation/slop in mind (including roof overhangs etc).

creeky
Member
# Posted: 20 Feb 2015 09:50
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saw a "solar" house in Alberta (dang. don't remember the magazine). Log cabin style.

The owner was interviewed and he sort of tossed in the "experimental" foundation they used. Basically a rubble foundation. then an XPS type 4 layer. Then poured a short concrete wall. Built the house on top of that. It's been in place for over a decade with no problems. And an extreme climate. and it's big house. 2000 sq ft.

felineman. maybe you could put a 4" xps layer on top of the rubble to raise the frost line. If you mated exterior insulation from the house to it you would have a nice insulated box.

I want to redo the foundation on my studio (skids on gravel). I've been thinking about just what is mentioned here.

My building is only 12x20 tho. and if it moves. well. no biggie.

felineman
Member
# Posted: 20 Feb 2015 10:31
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My issue is the land I want is 100 km from any road no fly-in or boat-in. So Its got a small path that will let me drive in but a cement truck forget it. I don't want cement or portland or any other POS foundation. I want natural. I would dig down to either clay or 1 foot below frost line, 12 inches of gravels or crushed rock, with a weeper pipe installed under foundation and then the weeper would go 50 feet down sloped to a pit with a 12 volt pump. stones would then be stacked slightly sloped to center double row to a height of 12 inches above grade. Being sloped inwards and being double row each row would fight to slide inwards against the other row making for a very strong wall without the need for mortar or cement. YES will take forever but also will last forever. I will be building a 12 inch square cut log cabin on this with 8 foot walls and 4x6 square log roof trusses covered with 1x12 planks and metal covering. I have my own portable sawmill. Everything that has to be bought in can NOT exceed 12 feet wide if I get the property. this trail is also over 40 km long and somewhat overgrown. Once I go out there I won't be coming back out unless its an emergency. I have 2KW solar system ready to go with 12 batteries charge controller and inverter, wood stove and almost everything I need including a 10K fuel trailer full (Don't ask how much to fill) There is no right of way to property only access across crown land trail and its about 3 hrs south of Hudson Bay not the town the body of water. Property size is about 2000 acres fully wooded with all water,mineral and tree rights including pine. I will be living in a travel trailer till cabin is built. Cabin will be approx 30x25 in an "L" shape with 8x12 foot deck. Compost toilet and rain collection with UV filter. Everything will be done to code hense the questions on foundation. I will never see a building inspector or anyone else up there but want it to last. So any information on the last detail of my build would be helpful. I also will have internet and tv thru satellite and property taxes paid thru bank so that travel isn't required more then couple times a year for general supplies.

CanadianNorth
Member
# Posted: 20 Feb 2015 11:10
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I'd suggest a PWF crawl space (4' walls) on compact soil. It's reliable if done right, easy to build, relatively cheap and fast. You may need a small excavator to dig the trench thought, but it would be worth it. A small piece of machinery such as a rubber tired excavator can do a lot of work for you, such as dig a well, put in a septic field, open up the building site, etc.

Steve_S
Member
# Posted: 20 Feb 2015 13:50
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Finelineman, sounds like you have all the essentials figured out. I think your frost line will be the scary part as I believe that's 4-1/2 feet at that location. Rubble trench foundations can work really well with a drainage tile @ the bottom. Ideally if you can find a spot that is high on solid bedrock like a granite outcrop or similar then you just build onto that... You'd likely need some of that horrid concrete for leveling but it would be minimal. Just a point of ponderance, French Drains always to the south and make sure the surface over the rubble drain trench is clear (sunlit).

As CanadianNorth suggests, the use of an excavator is seriously something to consider ! I used both a Backhoe & an Excavator for trenching and digging out my greywater runs etc... for a full week and that is after having full sized CAT 390 Excavator onsite for 2 days doing the "big grunt work".

I'm personally not fond of crawl spaces as they can be problematic in regards to water & critters. That being said, I'd consider it "if" the cabin was being built on a decent rise (good for drainage) where I could excavate into the rise for it... But certainly look into a "conditioned crawl space". More info @ buildingscience.com Cond-crawlspaces There is also the advantage of building that to also suit as a Root Cellar & Food Storage.

You foundation build will be limited to what you can get & what you can use. I somehow doubt that you'd be able to get mixed concrete and certainly would not get a cement truck up a 40km dirt path. 30+ Tons on mucky dirt, eeks.

XplorNet is able to provide Satellite up there for you (I'm using that right now). As a safety precaution, I have a small APC-350 backup UPS just for the satellite modem. Computer System is on a separate CyberPower Smart-UPS.

For your intended location, I'd also be thinking, snow shoes, x-country ski's, ATV (with big tires) Trailer & Sled, possibly a skidoo too and if water nearby a Canoe (one you can field repair). Avoid high tech & complicated kit, go simple & easy to repair even if less efficient... Efficiency means zilch if it fails to operate or cannot be repaired in the field.

felineman
Member
# Posted: 20 Feb 2015 16:11
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I have an old 80's moto 4 quad and an old 64 snowmobile snowshoes and skis. Ya I think I may be digging 4 feet down. shouldn't be too hard by hand I have nothing but time. I have xplornet myself and UPS backups. I won't be able to get a mini backhoe but I can hand dig it in about a week, stone isn't an issue as the Canadian shield has billions of metric tons of it everywhere free for the taking. Most of it sitting right at ground level. Sledge hammer and chisel is all you need. I've done a few stone stacked sheds and about a mile of stone stacked walls up north already so I have experience doing them. Don't think I said but foundation would be 2 feet wide with footings being 3-4 foot wide 2 over 1 and 1 over 2 stacked flat stone, not round stone. It all depends on how deep the clay base is. Anyone know of any books on stacked stone foundations WITHOUT mortar or cement. Don't forget if I use them I need sand and that has to be trucked in. Canoe is the one thing I have yet to find I want an aluminum one for ease of repair.
cabin1.jpg
cabin1.jpg


felineman
Member
# Posted: 20 Feb 2015 16:44
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I'm working on trying to find a better drawing program to do the plans for cabin Sketchup isn't working for me and autocad is just to complicated. Might just pull out the old paper and pencil its what I grew up on. If anyone knows of a program for logs let me know. BTW I might have gotten the property I'll know Monday. 2000 acres with all rights tree,mineral,water and even air rights up to 200 feet with deed from 1700's so government can't touch it for any reason. Its the original tittle before Canada was even a country. It does have a small 8 sq mile lake on property fed from a river from Hudson Bay. And I've been told there are even fish in it. Its about a 19 hour drive from me so I will probbly have to do two trips to get everything there as the limit is 75' 6" and I have a 32 ft trailer and a cargo trailer thats 34 ft. Plus the gas trailer that is another 21 foot. I will be using 100lbs propane tanks for fridge freezer and instahot water heater and backup heat. Without using backup heat I should be good for a year on one tank but will have 3 100llbs tanks. The sawmill is a bandsaw type with a propane powered Onan 12.9 HP engine capable of cutting from 1/4 planks up too 2 feet wide. Also have 3 chainsaws all stil 24" bar 14"bar and 12" bar complete with enough parts to fix them 10 times over. Quad was just rebuilt competely from tires up including rear gears. Snowmobile is in good condition with new engine and extra engine still in crate. I have 24 245 watt panels but won't use them all so I have backups, Battery charger is from an old railway station and can charge anything from 2volt to 72 volt. 3 inverters and 12 batteries to be split into 2 banks. I would suggest you getting a book called "Real Goods Solar Living Source Book" 30th edition is the newest edition. Its the BIBLE when it comes to offgrid living. I can provide an older public domain copy in this post but it doesn't have the amount of info the 30th edition has. I also have a personal library of over 200 thousand books ranging from animals to zoology ranging from early 1800's to 1950's. Below is a list of some of the sites I have collected this info from.

http://www.survivorlibrary.com/?page_id=1014
http://www.permies.com/forums
http://www.freeinfosociety.com/media_index.php?cat=6&start=0o
http://www.survivalistboards.com/downloads.php
http://www.tpub.com/
http://www.truthistreason.net/16-survival-downloads-field-manuals-and-handbooks
https://archive.org/
http://modernsurvivalonline.com/survival-database-downloads/
http://www.survivalebooks.com/usmilitarymanuals.html
http://www.naturalhomes.org/library.htm

I have about 50 more but that should be more then most of you can read in your lifetime. I also have all these books on DVD and its over 80 DVD's. My power requirements are Instahot tankless water heater, 5 lights,laptop,inkjet printer, Radio, and the few power tools such as drill,circular saw and router. Everything else is either gas or propane. I may add a tv and dvd player but I have internet for entertainment and lots of work to do. As you can see I have thought of almost everything I can as just have the foundation left and collecting what I don't already own, and a LITTLE packing. This will probably happen very soon if the deal for this land goes through Monday.

Steve_S
Member
# Posted: 20 Feb 2015 17:03 - Edited by: Steve_S
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Geez, you really thought about it, planned it and are certainly ready to execute "the plan". on the 64 Skidoo... indestructible ! Who needs TV when you have internet and don't have to suffer commercials and some blokes idea of what you should be watching & when...

Can't help you on the drawing program as I have a commercial Architecture Software (Home Designer Pro) but as you don't need draftsman / architect drawings maybe someone else could pipe up... The only other drawing program I use (free) is called Paint.Net which is very powerful with many addons and extras for virtually every task. It is comparable to GIMP and Photoshop.

Re foundation: google up "dry stacked stone foundation" which presents many hits. There is a few good articles / docs to be found. Like you, I am making good use of the glacial deposits here in the bottom of the Canadian Shield (I'm not far from Petawawa) but as is typical, it's a real mix of stone and I'd say at least 20% is useless for any kind of building. Not that there is a shortage.... LOL

--- edit
I should have added that sadly, the majority of the stone I'm getting off our property is more akin to round field stones. There isn't any good "flat stock" around for me to do anything with. You have a definite advantage there.

The only thing I think I would add to your foundation plan, which you likely already thought of, would be some kind of membrane / liner on the outside against the stone work to direct the water down into the trench and out of the walls. I was thinking along the lines of those EDPM plastic rolls dimpled for concrete or similar.

Hope it helps.

felineman
Member
# Posted: 21 Feb 2015 23:00
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I would like to hear from everyone, Ideas questions anything. I need to have everything questioned so that nothing pops up while I'm miles from nowhere. Lets talk it to death before I end up dead from something simple I've overlooked.

Don_P
Member
# Posted: 21 Feb 2015 23:18
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If it's square logs Sketchup should be able to handle it, circles are pretty crude.

As far as natural, mortar of some sort is in the evolutionary path of stonework going pretty far back, probably about day two. It provides a bed to distribute the load out over a broader area, the rocks are less prone to slip and there is much more friction inside the wall... if you keep the water out. I've seen clay used. Next step up is burnt lime or shells. We have limestone available locally and a couple of old kilns for burning lime are still in the weeds, this and river sand was generally the mortar between bricks or stones until the middle of the last century here. As the lime reacts with the CO2 in the air it slowly reverts back to limestone, it is also soluble enough that it tends to "heal". The romans discovered that adding a high silica volcanic ash with lime putty produced a good cement, several of their POS buildings are still standing .Clay is usually high silica and crushed bricks were often used. I imagine lime is scarce there though. More interesting old stuff if nothing else;
http://www.buildingconservation.com/articles/pozzo/pozzo.htm

You mentioned sizes of material, logs, rafters... have you checked the dimensions for the loads there?

Sounds like fun

felineman
Member
# Posted: 21 Feb 2015 23:41
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My issue is sand would have to be trucked in I have little clay and MUCH stone and timber. The foundation will only be 12 inches above ground so there isn't much rock to move. I agree that some sort of bonding agent would be better, maybe concrete or mortar on the above section but would rather not have to truck in any sand as its a 3 hr round trip. I've heard of using charcoal too but not sure how that would work. I need to also know how thick the foundation needs to be to support this cabin. Also looking for ideas on what to use to lift logs, I was going to use overhead cables or log ramps. Getting a crane in is not going to happen.

Don_P
Member
# Posted: 22 Feb 2015 01:12
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Gin poles work quite well. I've also built braced lifting towers that straddle the lift and dropped a chain from the crossbeam at the top. You can hook a come along to a chain and lift till it strokes out, then while #1 has the load, attach another come along to the chain as far above as it will allow, repeat, swapping the come alongs. You can climb as high as you have chain. A good rope block and tackle are very handy as well.

My wife and I have raised a 25' wide x 20' tall timberframe bent using a windlass attached to a rigid frame weighted with rocks. They didn't have cranes on cathedral jobs. I worked for one log builder, he would say "You've just got to outsmart the log". I'd consider piece-en-piece, log post and beam, for solo log building.

With much stone and gravel you can build a level topped gravel pad a good bit larger than the footprint atop a natural, draining, mound and then minimally rise above that with the foundation wall rocks. Load is considered to travel through most materials, and gravel, at up to a 45 degree angle. If you have a 1' wide wall on a 1' thick, well contained and compacted gravel layer, the load is going to spread over a 3' wide footprint.

Look around, sand is bound to be deposited there somewhere, either glacial deposits or streambeds, the quartz in that shield rock has got to have made sand.

felineman
Member
# Posted: 22 Feb 2015 02:07
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Could you dumb that down into detailed instructions. maybe a link or two. I've had a trip too the land and there is nothing but rocks no sand to be found other then clay about 5 feet down from the test holes and the standard soil. So 3 times the footing to 1 foundation thickness your saying? Anything you can direct me too on gin poles and other lifting aids would be greatly appreciated.

Don_P
Member
# Posted: 22 Feb 2015 08:22
Reply 


Here's a good foundation reference, including gravel footings under PWF foundation walls;
http://publicecodes.cyberregs.com/icod/irc/2012/icod_irc_2012_4_sec003.htm
Not 3:1, a 45 degree angle. Understand the concept, load can travel through the material at up to a 45 degree angle, rather than trying to remember that ratio, it'll bear more fruit later (without any engineering a floor joist is allowed to overhang its' bearing beam by up to joist thickness... that would be 45 degrees, you'll see the concept repeatedly once you look). In our example if you have 2000 psf bearing capacity soil then the rubble trench is capable of supporting 6,000 lbs per lineal foot of foundation wall. Macadam was the fellow that figured out that if roads were built of angular stones small enough to fit in a man's mouth they would bear load and hold up better than the roads they had of the largest rocks men could place. Adding tar as a binder with the gravel created tarmac. I assume he died toothless but happy.

It looks like there are tons of hits and some videos googling "gin pole". Jim Rogers on the timberframe and log board at the forestry forum has done a tutorial over there several years ago.

For windlasses or non geared winches the math is pretty simple. I used a 6" dia "drum" to wrap the cable around and had 4 spokes projecting 36" from the axle the drum was on, ~ 12:1 mechanical advantage, the person pushing down on the opposite handle also had a 12:1 advantage, it's simply a lever problem worked around a circle. Again the concept is all that is important, the details and ratios will change. You will be mastering simple machines.

Speaking of which, pipe is an excellent wheel for rolling timbers on tracks made of boards. The old egyptian log rolling method,even up an inclined plane, my wife reminds me they had more than one Isrealite.

I think I have some pics of "walking the dog". Basically 2 sticks joined to form an A with a chain or rope dangling from the cross. Straddle a log to be moved and lean the A away from the direction of travel and hook the chain or rope to the log. Push forward and the rising A will lift the log and move it forward. Replant the feet of the A and walk the dog again, slow but can move a ton or two by hand, for miles if you are patient enough.

Read up on parbuckling, with 2 logs leaning on the wall you can parbuckle a log up that ramp with ropes from the other side, I load large logs on my trailer this way but it comes from old log builders.

I've been smashed up by some of this stuff, when you are playing with big sticks you are a bug. You will be far from help. Some of these rigging concepts should be played with and learned closer to civilization, a broken leg out there would not be good. Be careful

creeky
Member
# Posted: 22 Feb 2015 09:50
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looks like you've got quite the plan. and done lots of research.

i know your trailer will have a propane fridge. but once you settle in you might want to pick up an electric one. as I see you have lots of solar. so for the spring/summer/fall an electric fridge will save you 1.25/lb of propane per day (average consumption of a propane fridge).

so you run electric for 250 days. that's 312 lbs of propane. and for the winter. well hang. the freezer is right outside. and keeping a cool spot is not bother either.

that's why I sold my propane fridge. it's expensive to run.

felineman
Member
# Posted: 22 Feb 2015 14:21
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A Propane fridge runs on either AC/DC/Propane 120 volt/12volt/and its actually .34/lb day. Small fridge. to run it on ac would be more then 2kw perday and in dc mode would be about 3400 watts even for a bar sized fridge. DON"T believe the sticker on the back. I have tested it with a device called Kill-A-Watt energy monitor. Propane is under 50 buck to fill a 100 lbs tank and will run fridge for over 5 months. I also have a freezer that uses about 1.47 lb day but its also a big freezer for meat and pelt storage once I get my trap lines setup. I want my batteries to be over 80 percent charged at all times. I don't have the income to buy 4k worth of batteries every year. I will run a laptop 50 watt/12/7 plus the sat dish and modem 30 watt/24/7 that is almost 80 percent of my power everyday. With the bulk being during the day. Still doing the calcs. This is based on a 5 hr day of sun at the min. 2 banks of 6 batteries at 248 AH should give me 3 days of power. I have backups of everything in case something breaks. The pump should come on more then a couple times a day and being 12 volt just has to pressurize the tank. Not sure total power requirements but its darn close to 2 KW per day. May need to add some more batteries. If someone wants to recheck my calcs please do, the math gets a little confusing.

Laptop 50 w/h x 12 hr
printer 100 w/h x 1 hr
lights 40 w/h x 5 hr
radio 5 w/h x 5 hr
Tv 35 w/h x 3
Modem/sat 30 w/h x 24 hr
Circ saw 900 w/h x 2 hr
1/2" drill 750 w/h x 2 hr

Plus other tools, as you can see even if I don't use any tools I am very close to my limit. I could shut down the laptop and lights but I want to plan for the worst so that when it happens I know I am covered.

Don_P
Member
# Posted: 22 Feb 2015 22:19
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Here's some pics, I hope

This is "walking the dog" Slow but a pretty good way to move moderate sized timbers when nothing else will work.

The rope or whatever is choked up slightly shorter than the upright height of the A frame. It's a leverage problem, on heavy logs you move in nibbles, lighter logs you can choke shorter and really move the log.

You can just make out the 46" circle blade of my mill behind the board on edge in the left of the shot.

This is a lifting gin I cobbled together from my Red Green pile to tip up the frame of my shop. The gin pole in this setup is the angled blue frame redirecting the pull. The windlass is at the right rear of the machine..."gin" is a very old abbreviation for engine, so this is roughly a medieval lifting engine.


Stopped for a minute to check everything and get a drink, my wife is walking around the right side. For this particular application I've set the gin pole down at this point and am directly pulling from the top of the tower.


This is the windlass end. The brake is set, it's the old motor scraper blade up top, it swings down to catch the spokes on the left end of the windlass.


Below is a shot of how they did it in the 1400's, two gin poles with windlasses at the bottom of each. They propped it to take a break and go get the tie timbers ready. So in 600 years, mine has a brake
rearingcruck.JPG
rearingcruck.JPG


leonk
Member
# Posted: 22 Feb 2015 22:46
Reply 


Look at army rigging manual, here's one location
http://www.wilderness.net/toolboxes/documents/tools/rigging/Army_rigging_manual.html

If you can dig 4'x2' trench manually in a week, you don't need an excavator

More importantly, the frost line looks to be around 3 metres(!)
http://www.raqsb.mto.gov.on.ca/techpubs/ops.nsf/20746bdcd064df1f85256d130066857e/94d4 961aa74fb84b852570c9006cfaf8?OpenDocument

You project sound like fun. If you let me fish in that like I can be your foundation on site consultant. (joke).

leonk
Member
# Posted: 22 Feb 2015 22:48
Reply 


there was a poster here - alaskaman - look up his build on permafrost, very similar squared log construction.
It was a link to another site, which since moved, if you can't find it - let me know, I may be able to dig it up.

Don_P
Member
# Posted: 22 Feb 2015 22:50 - Edited by: Don_P
Reply 


This is a jib mounted on the rear low slope rafter with a block and tackle to lift the front steep rafter over the greatroom hole.


The first attached pic is using pumpjacks to lift the ridgebeam into place.

Second pic is some ginpoles being used on a castle.

Third is a braced tower lifting the first of two 18"x24' LVL's for a ridge.
pumptimber.jpg
pumptimber.jpg
ginpoles.bmpAttached file: ginpoles.bmp
 
24.JPG
24.JPG


leonk
Member
# Posted: 22 Feb 2015 22:58
Reply 


don, these are pretty big frames!

One more thing, another poster here, fpw(?) has some nice pics of rigging, sadly he took his blog down, may be some of his pics can be found in his posts here or on forestry forum.

felineman
Member
# Posted: 23 Feb 2015 00:55
Reply 


Thanks give me a start anyways. Could someone check my solar system calcs? I'm thinking I may need to increase system to 2500 watts and add a few more batteries. I want the state of charge to remain over 80 percent 70 at the lowest. Also do I have to change to 24 volt system or can i stay with 12 volt over 2000 watts. I might have a chance to buy an old tractor with a forklift in 3 point position with 16 foot lift. Needs injector work and runs on gas. Crosses fingers. Anyone have any issues with more then 1 trailer behind a vehicle if you stay under the length limit.

Truecabin
Member
# Posted: 23 Feb 2015 12:26
Reply 


ideas

what about using large log beams and set the cabin on a small number of boulders such as 4 or 6

if one boulder sinks a little then shim it back level
if a boulder rises then take out a shim

for this you have to be able to move large logs and boulders to set in place
and you need to think about access under the corners if its necessary

it depends how stable you think the ground is at the site do the boulders there look like they heave in frost or do they stay in one place?

felineman
Member
# Posted: 23 Feb 2015 13:41
Reply 


I have shale like rock if you hit it it breaks into slabs not much round stone. I also want it too look good. Got the tractor today for 400 bucks also needs head gasket. waiting on final inspection from surveyors office before I proceed with land purchase, Try to get them to add a right of way on the logging trail. If you can call 2 ruts in the mud a trail. Looks like I might be moving up as soon as the ground allows wheels to roll. Need someone to check those solar calcs for me still.

Truecabin
Member
# Posted: 23 Feb 2015 16:41
Reply 


If cabin is more than 20 feet per beam size may get out of hand for boulder foundation but cabins on rocks are truecabins you could do 20x40 on 6 boulders. Shale doesnt sound like a good material for discrete load points.

12volts is easier than 24v because devices that run on 12v directly like 12v LED lights are easy to find and simple

if you go to 24v you have to invert to 120vac to run lights every night which is a further energy cost all the time. but theres something to be said for wiring the cabin for 120vAC its simple and sensible and if you want that go 24v or 48v

if the cables from your solar panels are longer than 30 feet, 12v can give trouble with voltage losses. its more complicated than that but many are using higher volts like 24 and 48 because their panels are away from the battery bank. For 12v you need the panels very close by or mounted right on the cabin. if your cabin site is in full sun that makes 12v more feasible

and i would say if you are really using more than 2000 watts you ought to be thinking 24 or 48v anyway

cant tell you what you are going to use. I dont think your printer is really going to print pages for a full hour every day but your laptop can charge for some time at 75 watts.

I usually run about 4 lights in my cabin which is plenty bright and it uses less than 20watts for about 4 hours in the evening which is about 6.7 Ah which I think of as a tiny amount of power.

i started with 12v and 1000 watts inverter but early on I found some very large feeder wires that go the 100 feet to my panels. Also I havent needed any more power so there i am. I think of 2000w as - twice as much as I need.

Better off with a 2kw generator for your construction tools. If you work solo you can use a 2k but if a crew you need minimum 5kw because the compressor turns on whenever it wants. Also pay attn that 5kw is only 2.5kw per leg so pay attn which outlet the compressors plugged in and keep your tools on the other leg. 7Kw is a better size.

felineman
Member
# Posted: 23 Feb 2015 19:14
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Only tools are hand drill and circ sw no generator but I do have one I can put on back of tractor. Need to rebuild the points in it. Was an old welder someone converted into a DC generator powered off the PTO. I'm using ac lights, computer and 12 volt water pump. The fridge and freezer is propane. I'm using a charger from the railways it can charge anything from 1.3 volt to 72 volt DC. and never has to be turned off as it regulates the power to trickle charge voltages. Only down side it has to be changed from DC to AC to do it. But I can spare the little power the inverter wastes to charge the batteries. I'd rather stay 12 volt maybe separate systems for water pump and lights? I have plenty of wire and could always make more then one bank of batteries. My panels are on the roof less then a 20 foot run from panels to breakers. Cabin will be built in a L shape with stacked stone walls 12 inch above ground at 5-6 foot intervals so that there is no span greater then 5-6 foot. Build it too last and it shall. Lots of stone work but also low maintenance. Roof will have at least R50 insulation and walls are 12" solid log for at least R30. Floor being 12 inch off ground and full stone enclosed will provide at least an R10 I guess with solid 1-2" tongue and groove flooring. Woodstove has an underside air inlet so I don't need to have air from inside cabin for combustion. One question with dry stack foundations how would you attach the bottom log to it seeing as there is no mortar or cement?

Don_P
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# Posted: 24 Feb 2015 00:18
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There's the rub, the bolt needs to be attached to something large and stable enough to be an anchor for the anchor bolt. Either epoxy into a honking big rock or use... mortar. A stone wall doesn't require that much. Since you are not going to hit frost depth, finding dry, free draining ground is your best bet for avoiding frost heave, or avoiding it as much as possible.

Wood has an R value of about 1 - 1.25 per inch, in the code standard the table lists R value by density. 12" is around R 18. The floor is R2, you will know this for certain the first winter. Beyond that, do it in 2 layers with tarpaper in between to block draft, an old board and board floor. It is good to triangularize sheathing when you aren't using plywood, sheathing on the diagonal makes things rigid. Use tarpaper or something between the rock and the sill log. The concept there, triangles are stable, frames with more than 3 sides are unstable, they need a diagonal or more to triangularize them and make them rigid.

Slate is shale that has been through more heat and pressure, if you have any good slate it can be very handy. Take some muriatic acid to check the rocks for lime, it'll foam up on a lime based rock, like a calcerous shale.

We've all read pioneer stories, a true cabin had a groundsill and a dirt floor, the rest is whatever we deem a cabin to be. If a 20 x 40 cabin in the north has its' sills elevated onto 6 boulders the resulting load on those boulders is going to exceed 12 tons each, with a soil that has a 2,000psf bearing capacity that is a healthy rock. A sill that would support those loads over a 20' span would also be impossible to move. The concept there is to think things through logically.

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