again, and again....Slab or piers

rsbhunter · July 24, 2012, 01:01:01 PM

Ok, i know this has been discussed a million times, but i am debating....i can dig the holes for footers and low piers (6"-12" above grade,pour the cement with rebar in sonotubes myself, or have the area excavated 8" or so and pour a slab. Is it a doable job for one person, maybe 2 to build the forms, screed and float a 20'X30" slab? I'll have to have the cement delievered, (12 miles on a dirt road from 7,000 ft to 10,000ft altitude) which might be prohibitively expensive right from the start.....The wants and reality might be two different things. A slab is better all around, but the piers "seem" to be more doable by one or two people...

Also, if the concensus is piers, should i go 8" or 10" sonotubes? This will be a 20x30 one story cabin, plans from Countryplans...As far as plumbing and sewage and elec, it will be a composting toilet, one storage tank water line run in under the foundation, and all power from solar no septic system, drain lines, or elec lines underground .rsbhunter

alex trent · July 24, 2012, 01:16:10 PM

I built on piers. Smaller place.

But if you are on fairly level ground, my vote is a slab. A safer bet all around...dealing with a lot of known issues and solutions with a slab. So many variables with piers that it will give you headache you don't need...and IMO you will not have all the info available, so will have to overbuild to safe.

July 24, 2012, 01:18:47 PM

Quote from: rsbhunter on July 24, 2012, 01:01:01 PM
A slab is better all around, but the piers "seem" to be more doable by one or two people...

Seems it really depends on where you are, how much money you want to spend. My daughter and I just finished building the piers and posts and beams for our 14x20 Little House. We did it by ourselves on a couple of weekends. It's on a slope so if I had considered laying a slab, it would have been really expensive. I didn't want to spend a big pile of money on a concrete base. I also like the piers because I want access under the house for an eventual grey water drain. It all depends on what requirements will make you happy really. The hardest part of putting in the piers was breaking the thick sod with a spade shovel. I think I lost 5 pounds that day!

MountainDon · July 24, 2012, 01:37:12 PM

If the concrete truck can't easily make it then consider a permanent wood foundation or build a crawl space using concrete blocks with the surfacing cement method.

One thing missed by many is that as moisture content of the ground changes the piers can and do loose much of the lateral resistance that they think the soil is providing. Yes piers are cheaper, when the structure is first erected....... And if there is a slope, all the more reason to very cautious, conservative.......

UK4X4 · July 24, 2012, 02:01:10 PM

10,000ft - in CO winter run off of that snow will soak the ground and need to be concidered

I'd think along the lines of squirls foundation- perimeter concrete footings and then blocks, either dry stack or surface bonded

you'll need to go to frost depth- mine is 48" at 8500ft

and consider snow depth too, I did'nt want timber sat under snow for 6 months

Another suggested foundation for the mountains from a local engineer was 48" of crushed rock with a bolted pre-built foundation over that, if your ground allows it.

www.intermountainprecast.com

From my small experience - you have to look at the gound make up first and then build for the land you have.

I needed a soil report from the HOA rules - but this provided me basicly the same information

http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm

July 24, 2012, 04:41:16 PM

Ok, so maybe i need to lean towards a slab....although the area for the cabin is supposed to have been graded flat????Will inspect (another subject) I am on one side of a road that is the top of a ridge , so there shouldn't be alot of run off from above, as i am maybe 3ft below the road height.....But, it is a real concern, as snowfall ia abundant!!!...Might have to check into the cost of cement delievery....Could the forms be done by an individual? Figuring i'm a fairly adept person, simple 20x30? Thanks for all the help...rsbhunter

firefox · July 24, 2012, 07:13:15 PM

Somewhere on here if I remember, was a discussion of using wood for forms that was then used for part of the structure. I believe they discussed how to prep the surface so that it could be easily reused.

Maybe some of the other folks here remember what I am refering to and can produce a link.

Bruce

Don_P · July 24, 2012, 10:11:56 PM

You mentioned excavating 8" deep for the slab and later that this is in snow country. The footings need to extend below frost depth or it needs to be done as a shallow frost protected foundation.

rsbhunter · July 25, 2012, 11:52:23 AM

According to one of the excavators i talked to, some of the people that live in the area are using piers to build on, that is why i had thought of that style....i also read in the book on cordwood construction (by Rob Roy) that on the U.S. -Canadian border (heavy snow country) that "floating slabs (4" thick) with 12" deep perimeter worked, as long as you have good drainage by way of a gravel base ( 4" or greater) compacted...that the slab is a stable platform to build on.....But, i learn new stuff every day....all advice is welcome...rsbhunter

July 25, 2012, 05:56:29 PM

As long as water does not saturate or move in to saturate the soil then it will not heave.
Where I am that determination would have to be made by a geotech engineer.
It's easier and makes more sense in my zone to spend that money on a frost depth footing.
That equation has several factors though

rsbhunter · July 26, 2012, 09:33:01 AM

In the end, i may have to bite the bullet and spend the $$$ to have a crawl space foundation, or slab done for me...This is my retirement home, and my goal is to have everything paid off 100% by retirement age (5 years, or so). But, if i have to go into debt, better now than later....rsbhunter

CjAl · July 28, 2012, 08:18:16 AM

i dont like slabs on a personal level. i am from the midwest where we have basements and houses on slabs just dont look right, too close to the ground.

also down here in se TX we have such bad termites. and the soil naturally builds up over time. slabs are so low its not long before you have soil at the wood. grading it back down every so often is hard on landscaping

Don_P · July 28, 2012, 08:57:40 AM

The slab under my living/dining room is raised about 3' above grade at one end down to ~1' at the low end. It's a case of unbalanced fill on the inside. The foundation then steps to a 3' crawlspace under the plumbed rooms, I poured a thin slab under there and don't regret it at all. The raised slab has radiant tubing that I plan to hook up one of these years.

rick91351 · July 28, 2012, 10:28:39 AM

My concern about slabs has always been plumbing. We poured a few that were poured with a footing, foundation and then filled with gravel and then the plumbing and heating was all run so they sat up in the air as a conventional home. However in areas here water is very unkind to plumbing. One town in particular until they put in their new municipal wells. WOW Short - very short life span...... Point is in fifteen years you were jack hammering due to pipes filled with minerals.

July 28, 2012, 09:33:22 PM

I debated on ours whether to do the plumbing over a crawspace, which is what we did, or whether to keep on with the raised slab, running a 3' dia culvert down the length under the slab. Use that as an underslab chase and drop the plumbing into it through sleeves. It started sounding like more trouble than the crawl, but something else to consider.

rsbhunter · July 28, 2012, 10:31:49 PM

Ok, i understand about mineral build up, i'm in S.E. New Mexico now....the water here eats holes in copper pipe....honest. There will be only one pipe in, and one out for grey water....the one in from a 1500 gallon tank...Toilet is composting type..This will be rustic...i'm not fooling myself...i'm going solar , wood heat, basic on everything......My idea of retiring is to NOT worry about bills, and i have not deluded myself about what the lifestyle entails.....I tent camp at 9500 feet, with lows in the 10 degree range, although, that's not a magical bullet to keep away hard times, just that i do know what "roughing it" is....The foundation/pier/slab-crawlspace has to be figured out first, obviously. Next time i go up, i'll drive around the area and see what lind of soloutions others have come up with....Sometimes what we want, and what has to be, are a ways apart.....rsbhunter

rick91351 · July 28, 2012, 11:42:23 PM

Roughing it ten years ago seemed challenging and fun.

Now that I have retired it is well not so special.

I just do not think I would build anything that I could not plumb or remodel for more creature comforts at a latter date.

Check with your county and find out what snow load requirements are for your area. Our ranch property is 120 pound snow load requirements and major wind load engineering as well. I do know where my property is located the cost to build is not cheap. If I was really concerned about building on the cheap so to speak I would never choose there. I would choose down in the valley where permitting is way cheaper, and engineering is not required. Up there everything considered a human dwelling or domicile is engineered. Cement is way cheaper in the valley, up there - there is truck time, mileage and then a out of zone charge, and then a fuel surcharge, and we do not even have any concrete in the truck yet. The last I poured up there was like $175 a yard when we did the figuring and that was two years ago. http://countryplans.com/smf/index.php?topic=9342.msg120056#msg120056 Building materials in the valley are cheaper as well. Because you are not saddled with the fuel cost to transport unless of course the lumber yard will haul them for you without tacking on delivery fees.

Right now I am looking at the options of what to do where we want to live. The ranch has a orchard and our new shop. This time of year I have to travel up there to water the orchard at least once a week. We have over 100 trees and 50 blueberries and about 150 plus feet of raspberries, and we have started some grapes up there as well this year. I'm to point of saying this is not affordable having two places. I am more than content to live here, yet up there was the place we always figured we would land when we retired. So we planted a huge orchard http://countryplans.com/smf/index.php?topic=11346.msg155059#msg155059 and a mini orchard http://countryplans.com/smf/index.php?topic=10850.msg158920#msg158920 But it is not cheap to build or live there with the current price of fuel in fact it is sort of stupid to even own it.

flyingvan · July 29, 2012, 08:06:33 AM

If you're building according to concensus, my vote goes to the perimeter foundation. There's ways you can do it yourself, the plumbing is accessible (or you can add it later), you keep a lot of the moisture out of the house, you gain securable storage space, you can work with the slope, insulate your floor and deal with radon. (I did both of my builds with no prior experience, using fabric formed foundations. The only day help with both projects was hiring a concrete truck and pumper for about 2 hours so there would be no cold joints) but cinderblock is used a lot more frequently

rsbhunter · July 29, 2012, 07:25:40 PM

Well, as far as roughing it anymore, those days are fading in the rear view mirror.....hence the cabin.....as far as plumbing, like i stated before, there will be a 1500 gallon tank....and a grey water line out...future plumbing won't happen...i'm at 10,000feet...it will be cost prohibitive to drill a well. This is why solar is the way i'm going...power is 5 miles away, figure the cost of bringing that in!!!!!!!!......so, this is what it is....i understand that i could have bought land in San Luis Valley, cheaper even.....heck, i could stay where i'm at, 3bdrm, 1-1/2 bath, grid, city water, etc....But, i don't think that is why most of us buy these plans, and build these cabins/small homes....I'm not lookig for "Sunset retirement home" Iv'e dreamed of this for many years,,,,wish i was younger, but other than that, iv'e always taken what life offered, good and bad.....So, i'll do some checking on cost of the different options, and see what comes of it...rsbhunter

Checi · July 30, 2012, 09:55:42 AM

Quote from: rick91351 on July 28, 2012, 11:42:23 PM
Roughing it ten years ago seemed challenging and fun. Now that I have retired it is well not so special. I just do not think I would build anything that I could not plumb or remodel for more creature comforts at a latter date.

I am more than content to live here, yet up there was the place we always figured we would land when we retired.

I'm with you on this one Rick. I'm building my 30x30 log home with retirement in mind too. This little house I'm building will be a roof over my head while I build the big house. As much as I can admire those who will live with the composted toilets and ladders to lofts and other such things, in my OLD AGE, I don't want to be hobbling my old bones out of a warm bed in a cold cabin in the middle of the night to climb down a ladder to sit in a wood box of a toilet on my deck. Suffering does NOT keep you young!!

July 30, 2012, 12:18:39 PM

You are right, i won't be going out on the deck either....cold or warm...The compost toilets vent thru the roof, and they are in a "bath" room like any other comode......They cost more, but it's cheaper than $5000.00 for a septic...(and that is a quoated price)....You are 100% right, suffering does not make you younger, nothing does that.....Like the saying about life goes "don't take it so serious, it's not permanant"....rsbhunter

rsbhunter · July 30, 2012, 12:29:03 PM

This is what i'm looking into doing....this is upper state N.Y......probably similiar frost/freeze conditions...

http://www.countryplans.com/velsko.html

Don_P · July 30, 2012, 09:24:27 PM

I've had more reason to think harder about composting toilets of late. For about 2 months I fought a really nasty antibiotic caused bacterial infection that really messed up my public works department. The nurses would scrub and glove in my presence, they considered me and especially what came out of me contagious. And boy howdy did it come out of me, I think it would have overwhelmed a composter. We also maintained a high level of washing, etc. I'm not really sure the conventional system survived. So first off for a permanent residence you will get really ill at times. How will the composter handle it? Second, or number two, can be something you want out of your presence quickly, entirely and without any possibility of contamination, vectors, etc.

rsbhunter · July 31, 2012, 12:41:15 PM

I believe that there are times when i might have to accomadate a special situation.......You're right...but, it is not going to happen where i'm at....i'll have to come up with a plan "B'.....Outhouse, bucket, something.....but , now that you've brought that up, it is worth researching some other forums about it.....i know there are people out there who live year round with them.....Thanks, i wouldn't have thought to research it , if you hadn't said something...rsbhunter

Squirl · July 31, 2012, 01:30:53 PM

As far of the "away" out of the building part, there are options for that.
http://www.sun-mar.com/prod_flush_cent3_acdc.html
I have designed mine to flush to a unit that is insulated, heated, and on a slab next to the house.
The reason I brought that up is it may factor into the design. Everything flows with gravity. So if going with a remote unit, it has to be 2-3 ft below the toilet height. That would eliminate a slab, unless you are putting the bathroom on the second floor

As far as the illness part, that can be a challenge. The system is designed to work by beneficial bacteria. High dosages of anti-biotics can kill all the beneficial bacteria in it, stopping composting.