What's the best option for a small cabin foundation?
DIY concrete footings? Precast? Treated wood posts? No footings at all and just put the cabin directly over gravel?
Best footing/foundation for a wood cabin?
What's the best option for a small cabin foundation?
DIY concrete footings? Precast? Treated wood posts? No footings at all and just put the cabin directly over gravel?
How cold is the area? How windy? You should always anchor it.
Cheapest way is just get some buckets, fill them with crete and bury them, essentially making a plug in the ground.
>How cold is the area? How windy?
Should rarely go below -10°C (14F). Some wind, it's in the mountains at 1300m of altitude (4200ft).
piers probably need to be at least a foot below ground level for frost line there...maybe 2ft
your picture is some blocks over a patio slab
do you need more
Some people just put wood posts straight to the ground like that, and I'm wondering how long these would last and what kind of treatment would be the best.
'The best' depends on materials and local conditions.
Concrete piers would be a good choice...
Are there conditions where concrete wouldn't be the best choice? I heard they can crack, especially if done yourself, but precast tend to do better.
I'd go precast for convenience.
I'd also compare material costs to a 20 or 40" container as they're instantly usable, last many decades and are very easy to work with. (I have four 40' High Cubes and a 20' standard so this isn't one of the gasworthy larping imitation crab meat living on mongtards suggesting something they never did.)
Tincancabin did it nicely but expensively because he started out without a long hardcore applicable background or much container knowledge. He also had plenty of cash. It's easy to add containers over time which I've also done without using heavy equipment.
Fire of course easily destroys wooden structures but a generous firebreak helps. I don't waste time with wood since a container can be deluged with embers and remain undisturbed if a decent firebreak is cut around it.
They won't last long. Treated would doesn't use the old toxic stuff that made it last like before.
You can use them as long as the ground is solid and you're OK with replacing them in 10-15 years depending on the moisture level.
>You can use them as long as the ground is solid and you're OK with replacing them in 10-15 years depending on the moisture level.
How doable is replacing the fricking foundation of even a small cabin?
>How doable is replacing the fricking foundation of even a small cabin?
You just need to jack that shit all up.
However if all your piers are fixed to the structure like pic attached then it must be a fricking nightmare to disconnect them. That's something to think about while building the foundation...
>How doable is replacing the fricking foundation of even a small cabin?
Pretty easy. You can do it with a regular car jack. A small 12x12 floorplan? Hell, a guy could probably lift that with a rock bar.
It's not all that complicated. You could take a length of #80 PVC pipe, fill it with concrete with a plate at the top and bolt right to that. It'll be there for decades.
I soak cribbing in waste oil and pour it onto the old RR ties beneath my shipping containers. Wood is pleasantly spongelike.
Depends on how wet it is. Wood posts in the ground like that here in Western Washington last maybe 5 years even if they're "treated". You need to put that shit in concrete and shape the top of the concrete so water runs off the edge and it's elevated off the ground an inch or so.
Something like this
is a better idea still, this prevents the wood post from even being in contact with the concrete in the first place.
You can do even better cheaply using steel pipe or heavy I-beam which is easy to find surplus. If you score structural posts from a demolished building you already have the end plates installed and since most are double ended cutting one post yields two shorter posts.
Attach posts to house frame, level frame then fill hole with concrete mix. Steel doesn't rot or burn, termites don't eat it and it's very easy to work with. When I poured my shop slab I used I-beams for the outer box which is both foundation and form. I welded pipes to the base beams, flipped the pipes into holes I'd dug with a post hole digger, leveled beams with cribbing, complete the box with two more beams welded to the first, reverified level then had the slab poured (my back is destroyed so no floating concrete for me). That got me a foundation I can weld or bolt to which I did.
Wood prices being silly these days I'd keep alert for surplus steel. Most sellers get it free from doing demolition jobs so they have freedom to barter it. Guns make great barter so I keep an AR handy for trade bait. Bubba's wife may object to him buying a fun but can't argue with barter. A cabin with a steel foundation solves problems before they happen. Steel studs etc are nice too so run the numbers on different ways to get the cabin suiting your esthetic and financial situation.
did you use metal decking inside the box? essentially an elevated slab?
I did better and poured fiberglass-reinforced concrete atop RR gravel for my slab since it's a shop. Steel decking would suit me fine but I don't have a cheap source that would have beaten concrete. If I did I'd have welded it like a barge deck with .045" flux core from my suitcase feeder.
OTHO my chicken coop building which is built to home construction standards (so it could be more shop space if we got bored with chickens) is on treated wooden skid I'll have to raise because though only about 15 years old the skid is beginning to rot.
6 years ago I painted regular Doug fir 4x4s and buried them directly with concrete and they haven't rotted at all for a fence when I was feeling cheap.
>straight to the ground like that
Those posts are probably set in some concrete footing.
>Some people just put wood posts straight to the ground like that, and I'm wondering how long these would last and what kind of treatment would be the best.
generally speaking if you put wood in the dirt, or near the dirt, moisture will frick it up and rot it away fast.
Maybe thats fine if you want a cabin that lasts 7 years, but if it were me... just do pressure treated wood onto concrete footings. Its not even that hard and you'll have something that can last a lifetime if taken care of.
Gotta say, youre kinda lazy for even asking. You should know that you shouldnt bury untreated or even treated wood in the dirt. Its so obvious.
>Its so obvious.
It did seem obvious to me, but then I ended up watching several videos of people doing just that so it got me wondering whether it was that bad or not.
yeah well, lots of stupid asses out there doing dumb shit. Gotta be careful with taking advice from strangers on youtube, especially broke diy:ers.
Is shit like this not easiest? Pour/bury whatever concrete you want, drill this into it, seat some 4x4.
do this. with sonotubes or something, or make your own forms. do not bury wood in dirt or concrete
>Drill?
What are you drilling? Just drop it in the wet concrete before it sets like a normal person
look at the picture dingus. Unless it's epoxy coated a metal footing will rust out after being in concrete long enough. By using one like the picture up there you can just jack up the cabin and swap it out when it starts breaking down.
>Unless it's epoxy coated a metal footing will rust out after being in concrete long enough.
How long do you think that concrete will take to harden? Do you think it won't continually get wet after it's cured? Who gives a shit about the rust that will form from 1-2 days of being in the pour. If you're that worried I guess you can put spray paint on it and waste 3 dollars to fix a non issue you invented in your head.
read this dingus https://www.cement.org/learn/concrete-technology/durability/corrosion-of-embedded-materials
Do you think this dude making a jack shack is going to spend money on coated rebar and posts when huge buildings don't even use coated rebar in the foundations?
follow the thread of conversation better dingus
this, it's what I used making my deck and works great. drill four holes with a tractor, fill it up with concrete, drop a 120mm rectangular prism of rebar in sticking out another 20cm and a sono tube around that and put additional concrete in that to form a big base with the smaller concrete pier.
then just short wood legs up to your floor joists, the wood legs take up the difference in height of the concrete so you dont have to frick around with ground leveling or be careful with the concrete.
Civil Engineer here, depends entirely upon your design considerations, budget, geotechnical conditions and how long you want this cabin to last.
For design, you'll want to consider how large and how heavy your structure will be. A basic log cabin type structure with maybe some wooden furniture in the dimensions shown in the picture would be fine on some pretty basic foundations, like something you'd do for DIYing a deck. Keeping it raised on piers removes any problems with water ingress as well. Here's where I'll recommend hiring a licensed professional engineer to make the blueprints for you, even though you probably won't. Having blueprints will help your structure not collapse during extreme weather or simply fall apart and being a massive fricking headache a few years down the line.
Budget wise, consider what equipment you already have. If you have a huge dually truck with a crane on it that can offroad to your construction site, feel free to go with precast footers and piers. The most economical option is wood stuck into concrete. Pick your poison for your wallet.
Geotechnical considerations are just so you don't build on a sinkhole or an area with the potential for a mudslide or something. This goes back into hiring an engineer, cause you certainly can't make sense of a driller's report lmao. Judt make sure your footers are below the frost line.
As for how long you want your cabin to last, be realistic. You don't need this thing to last generations, it's a log cabin more or less. More longevity = more $$$. Be economical, but don't cheap out on the structural elements. This is just to say you don't need to build a complex foundation for what amounts to a fancy shed
Thanks for the help frens.
>A basic log cabin type structure with maybe some wooden furniture in the dimensions shown in the picture
I'm actually gonna do an insulated stick build, so it would be lighter than full logs. Definitely not bigger than the picture.
>Here's where I'll recommend hiring a licensed professional engineer to make the blueprints for you, even though you probably won't.
You're right, I probably won't. Just gonna do tons of research on all the ways these things can fail.
>The most economical option is wood stuck into concrete.
Should the wood be at ground level or is it better if it's raised by a few inches? Also what's the best treatment for the wood?
Also, what would be the advantage of wood posts in concrete vs laying the cabin directly on the concrete like in the OP picture?
So tell us then anon...
> footers below the frost line
Probably the most important thing
No offence to engineers, but looking at OPs photos, it might double the price of the project to get the geo survey and design done
Just go for and let motherfricker fall over in 20 years and the build another one for the same price as getting it engineered. Chances are it won’t fall over anyway so you’ll be fine
it's a cabin not a house
if one post no longer touches the ground you just toss some gravel back in
or if it sags then you hammer some wedges in
talking about foundations and shit is nonsense for a cabin
>The most economical option is wood stuck into concrete.
A handful of Simpson post bases is less than $100 and will stop the wood from rotting inside the concrete in 5 years
it's also way easier to get a nice square and level layout, which will make the rest of the build go smoothly
putting wood directly into concrete (even with a sleeve, tar or other treatment) is Africa-tier construction
>rotting inside the concrete in 5 years
you know-nothing morons on here are constantly whining about this and yet I've never in my life actually seen this happen. Seems like another wives tale that started up at some point and enough people repeated it that it's now gospel. I've got 20-year-old posts in my backyard that were sunk directly in concrete and they're still standing strong, won't budge an inch. I've seen older too, my buddy's deck built in the 80s is on posts sunk in concrete and there's zero sign of rotting or moisture damage of any kind on the posts.
not the anon you replied to here. Well shit for brains, just because you saw your trailer home neighbour do it, doesnt mean its the right way.
Typically over here in the civilized world, (untreated) lumber is never, ever, supposed to be in contact with concrete. It may be more important in basements due to lack of ventilation. Either way moron, building rules exist for a reason and that reason tends to be experience.
Go kick rocks homosexual.
don't care, didn't read, I know more than you and I also make more money than you
cope and seethe
You can tell from 'neighbour' that he's Canadian, British or Aussie and thus, a moron that knows nothing.
how many genders do your people have in your "civilized world" ?
>you know-nothing morons on here
I do timber framing and decks for a living, and a lot of our money comes from tearing down and replacing shitty stuff that was done poorly. I have seen a lot of rotted posts.
When you do it professionally you get a big sample size, instead of just you and your neighbor's house. When your shit comes with a 25 year money back warranty you do it the right way.
If you don't care about your builds or take pride in your work, don't want to pass them on to your kids, etc that's on you.
I hope you reply to this mister timber framer. I would really like to pick your brain. I'm in the building trades and I do electric, so I am not an expert. But I want to know the real answers as to how to make a structure last as long as absolutely possible.
What are the best ways to make a foundation for a timber frame shed? Piers, and footings, okay, but how do you interlock the shed with the foundation, in a way that will last 100+ years (if possible)? In addition, I was going to build a light frame 2x4 type structure on the outside of the timber frame shed - easier to install windows and doors I think. What kind of sheathing and cladding should I utilize? Finally, is there a way to place a woodstove into a timber frame structure where the stove is on masonry as required by code - or does it heat the timbers around it too much? I assume copper rooves are the most long lasting but I wouldn't immediately resort to the most pilferable by scum, so if you have ideas about that, I'm all ears.
The best option is slab on grade, with footing piers under each post. This will also accommodate the woodstove, and as long as it's not within maybe a foot of the timbers it should be fine.
Using coated metal brackets like in my previous post is good for posts, whatever works though as long as they're not touching concrete.
I would say Zip (tm) sheathing against the timbers, with furring strips running vertically outside to create an air gap between the siding and the structure. Metal siding is the most durable but doesn't look great.
For framing windows and doors just use PT sill plates and use as much of the timber frame as possible, i.e. in the picture you don't need a header above the window because of the beam.
For roofing we use plated steel, it's warrantied by most places for 30-50 years depending on the exact product and supplier but will last a bit longer than that.
A single slope roof pointed downwards towards the lowest grade point will usually be the best option. Generous eaves overhangs will protect the walls and siding from weather, I like at least 18"
Itt people that know nothing about construction
Thank you for your meaningful insights
Sonotubes //concrete below the freezing depth of the soil // smooth + taper the top of the footings and have some kind of anchored saddle for bolting onto. To taper the concrete, put extra concrete for each footing in a bucket... as it starts to firm up a bit then you can trowl it onto the footings and shape it nicely. Put some wet papet towels covering the concrete once it is hard yet still wet.. reape the whole busoness up with saran plastic wrap, really tight around the sonotube and work your way up. Bonus points for reapplying water for a few days into the wrapped footing to get a really good strong cure.
Don’t forget to have a footing at the bottom of your concrete piers, and gravel for drainage. See pic related.
Yeah, that means you can’t just do it with auger and a straight hole, which makes it a pain in the ass but if you want to do it right you need the big foot. Lots of cheap skates do a straight hole… but then the consequences may never be the same
Interesting
Ty
put pressure treated posts directly in dirt and it will last 15-20 years. This is a cabin, not a house. Don't pretend like you'd rather make a 70-90 year foundation with all that work for cement when you can put a 10 dollar 4x4x8 right into the dirt and if it ever rots decades later just replace it in a day.
That's fine and all, but how on earth do you replace a 4x4 in the ground under a house? Do you lift the whole house up 4-6 feet in the air so you can re-dig the hole?
>but how on earth do you replace a 4x4 in the ground under a house?
tunnel
Yes. They are called foundation jacks, you have to go slowly and it will take a long time, but you literally lift the house in the air.
>you literally lift the house in the air.
They remodeled a house near me, a small older house, probably two bedrooms, kitchen, family room and one bath. They jacked it up far enough to walk under. I suppose that made it a lot more comfortable to handle new hvac, plumbing, electrical, plus a new foundation. Then they lowered it back down, and with new siding, windows, roof, etc., you had a new house, sorta.