View Full Version : Building on sloped land


lockness
11-15-2006, 12:48 PM
Im hoping to start planning a new shop behind my house. My one concern is the land behind my house sopes downhill. Not sure how to measure it but if I picture a horizontal line, Id say the slope is downward around 25 degrees.
If I build say a 30x30 shop Id imagine the back wall would need to be at least 10 foot high to level the shop. Anyone have experience on building on sloped land? Im really concerned about the cost involved in making the land usable. Almost to the point where I may consider moving :( . Id like something pretty simple like a pole barn but if I need to bild up a big foundation then it seems I might as well go with a stick build. Any thoughts/ideas on how I can tackle this?

junkman104
11-15-2006, 01:19 PM
I had a 30x50 put up back in August and had the same problem. $4200.00 later I had a level site to build on. It aint nothing but a thing. I have 12ft along the side and back with a swell cut for drainage and plan to plant some juniper to protect the bank. We finaly got the C.O. and get to move in the new house this weekend :beer: :beer: :beer:

http://i7.photobucket.com/albums/y253/Junkman104/Picture378.jpg

http://i7.photobucket.com/albums/y253/Junkman104/Picture416.jpg

http://i7.photobucket.com/albums/y253/Junkman104/Picture540.jpg

http://i7.photobucket.com/albums/y253/Junkman104/Picture537.jpg

mjribeiro
11-15-2006, 01:27 PM
I had a 5' lowside, 900 tons of fill later it's nice and flat. 600 tons of quarry process, spread and rolled with a 9 ton vibratory roller - 300 tons of fill around the perimeter. That was a 6 digit escavation job!

Bolt11
11-15-2006, 04:31 PM
Depending of course on the soil quality and how compacted you want it to be, if it works out for the site layout it is often possible to take the dirt from the high side, put it in the low side, giving you a level site about half the hieght of the original hill. This way you don't have to buy and haul fill, so it would be relatively inexpensive to do. And for a 30x30 it can't be too much.

jhchoppers
11-15-2006, 05:10 PM
We had our 25 x 40 built on a hill. We just notched out the hill.

8406 8403
8404 8405

Click here (http://www.jhchoppers.com/newshop/index.htm) to see the entire build

Crazy Legs
11-16-2006, 10:10 AM
i'm working on this same problem in my backyard, my slope isn't near as bad as 25 degrees but i may have to add 4' to my back to bring it all up to grade, so far i've brought in 26 tons of fly ash and i'm working on building a retaining wall out of railroad ties, and alot of broke pieces of concrete.

Keep me informed on your progress!!!

twostory
11-16-2006, 01:05 PM
I built footers, then a 41 inch tall stem wall for most of my garage. My property drops about 4 feet over the entire 44 foot depth of my garage. I then demo'ed and dumped the driveway concrete in the newly formed pit. Then I had 9 dump truck of fill dirt, compacted in 4 to 6 inch lifts. Then I topped this off with one dump truck load of #57 gravel. The slab sets on top of the gravel base.

My wife & I did almost all of this work, but I paid a crew to pour the slab. I built wooden forms for the stem walls. Reused this wood when I framed the garage.

Once you go over a 4 foot high wall, you normally will need an engineer to design it. So stay under 4 foot if possible.

If you can dig into the hill, and create a level spot that will save you thousands of dollars and time. A bulldozer and experienced operator can do this work in an afternoon.

Goto my profile for a link to my garage build.

Goodluck

lockness
11-17-2006, 12:41 PM
I cant really dig into the hill since my driveway will be coming downhill to the shop.

My situation is alot like jhchoppers. Could you share an estimate of what it cost to the foundation you had done? I know having a pumper truck isnt cheap.

GTS225
11-17-2006, 05:13 PM
This might sound outlandish, but........... Might it be possible to pour a "terraced" slab to build the garage on? (Local codes may have a big say in this.) Seems that if it's permissible, one could pour the slab in such a way that the center, or one side of the building would give quite a bit of overhead, thus allowing room for a lift, or taller vehicles. It may be a bit of a hassle in the interior, but if it could keep the initial price quite low........

Roger

Ironcrow
11-17-2006, 08:05 PM
I just made this post in a thread about block walls:

"I have a 12 inch thick block wall on my shop. It is 14 feet tall and is a retaining wall. The grade behind garage goes up another 9 feet. Yes, the back of my garage is, essentially underground. Did I mention my lot is steeply sloped? In my case, the 12 inch CMU (Concrete Masonary Unit - "block") wall was selected as an alternative to a formed and poured solid concrete wall. There are two 5/8 inch rebars in every cell, four per block. The entire wall is poured full with 3000 psi grout. This is more rebar than the architect and engineer came up with, but I got a good deal on the rebar and I like overkill."

I would say, bite the bullet. Have an architect look at what kind of retaining wall you need for a level floor. Realize it will cost you. Make a decision to go for it or find a different site. Don't compromise with a smaller building, uneven floor, or piling up fill dirt to the moon to get a level spot. You'll hate the compromise.

Sundowner
11-17-2006, 10:25 PM
did you say TWENTY FIVE degrees?
that's like a 1 on 4 slope. that's huge.
we were in Hawaii a few days ago and the road down into Waipio Valley is 25 degrees. it's mf'n terrifying, and they don't even let you drive it unless you have 4wd with a low gear.

I would reccomend that you do a combined borrow/fill earth move.

build a modest landscape block retaining wall into the low side of the slope and "borrow" earth to fill it from the high side of the slope to fill in behind the wall. cover the excavated high side with some geo textile prodiuct to protect it from slide and erosion. savvy?

the down side of this is that you will have to use the middles of sides as the egress for vehicles. not a big deal for a square garage.

trs900
11-18-2006, 07:01 AM
http://i112.photobucket.com/albums/n187/trs900/P1010117.jpg

I had the same problem, reason I decided to build up instead of digging out to get it level was for drainage as I did not want to be constantly fixing wash out around building with all the water draining towards it..

Herb
11-20-2006, 01:10 PM
We had our 25 x 40 built on a hill. We just notched out the hill.

8406 8403
8404 8405

Click here (http://www.jhchoppers.com/newshop/index.htm) to see the entire build
Boy, what a big waste of space that was. I had a very similar situation so I put a full basement with a roll up door there instead of filling a nice spot like that with dirt.

sharpshooter
11-20-2006, 04:21 PM
Boy, what a big waste of space that was. I had a very similar situation so I put a full basement with a roll up door there instead of filling a nice spot like that with dirt.



When I was looking at the pictures I thought man thats gonna be a nice spot for some extra storage then the next pic it was filled in, I was surprised, but hey Im sure he had his reasons on not using it.

jhchoppers
11-20-2006, 04:46 PM
The cost for our build was 27K. This only was for the outside work, no electrical, insulation, or sheet rock ... We are doing all that ourselves.

I did call on some buddies to help, but I paid them $20/hour. Just make sure you get several estimates. We got one as high as 58K for the same thing !!!

I would call several concrete guys yourself, to get a ball park.

Also, in hindsight, I should had put preformed concrete form floors in, then I could of had a basement for about 7K more. Our first estimate for the basement was 20K, but I found a guy who would of done it 7K after the hole was filled with rock

Hope this helps

KELLHAMMER
11-20-2006, 07:08 PM
I designed a 30 by 60 garage. Two levels on a steep lot. We used a concrete plank to create the second story garage floor. The attic is an apartment.

KELLHAMMER
11-20-2006, 08:09 PM
This is a garage I designed for a friend. We've been building it for about 6 months. It was a barn for horses. We turned into a 5 car garage. The upper half of the original is going to be for the kids to hang out. The new addition has a 14'-0 ceiling so the will be no interference for the 2 post lift. Notice the sloping track for the 16'-0" wide garage door. It has a 2 zone infloor hydronic radiant heat system. Powered by 40,000 btu electric boiler.

lockness
11-21-2006, 10:48 AM
The cost for our build was 27K. This only was for the outside work, no electrical, insulation, or sheet rock ... We are doing all that ourselves.

I did call on some buddies to help, but I paid them $20/hour. Just make sure you get several estimates. We got one as high as 58K for the same thing !!!

I would call several concrete guys yourself, to get a ball park.

Also, in hindsight, I should had put preformed concrete form floors in, then I could of had a basement for about 7K more. Our first estimate for the basement was 20K, but I found a guy who would of done it 7K after the hole was filled with rock

Hope this helps

Wow thats not bad at all for that much work. You have given me hope. Thanks for the ideas.

kcclark
09-10-2007, 01:07 AM
I need to build a garage into a slight slope. Ground is around 2' higher at the back versus the front. Garage ceiling will be 12'. Topping off with gambrel roof for attic.

Was planning on using poured concrete for walls but $ situation has changed (gotta spend some on another project). Is a pole building out of the question because of the back/side walls being partially underground?

arbee
09-10-2007, 10:09 AM
You can see the details of my situation here: http://rbgarage.googlepages.com/gradingandfoundation

I "only" had a 6 ft drop from one corner to the other though.

JMURiz
09-10-2007, 10:13 AM
KELLHAMMER: Those are some awesome designs!

Lockness, you should contact this guy, those are some nice looking ideas.

PAToyota
09-10-2007, 11:08 AM
Is a pole building out of the question because of the back/side walls being partially underground?

You would not want to backfill against a pole building. But you could pour or lay block walls up high enough that it is out of the ground on all sides and then frame on top of that.

Bigger Hammer
09-10-2007, 11:40 AM
If I were in your shoes I'd seriously consider a 2 story type structure where you can have a workshop below and an elevated slab for parking above. Since you are already driving to the high side anyway you would basically build your garage with a walkout basement. While an elevated slab or precast slab panels might get into some big ching it wouldn't surprise me if it was comparable to an extensive earthwork scope. Not to mention, earth workers are notorious for sticking it to ya if they get into something that was unforeseen.

Here is a pic of a 1940's cabin rebuild I did about a year and a half ago.

Hillside const. (http://www.contractortalk.com/attachment.php?attachmentid=1924&d=1144466740)

I dug the foundation into the hillside and backfilled the crawl with the spoils. But in your case you could do something similar and simply pour a slab instead. There would be a lot of dirt coming out of the hillside on a 30x30 building but it wouldn't be hard to burn it up around the perimeter after the foundation was in place. btw, the slope on that cabin was intimidating to look at but it was steep!! the foundation is only 12' from front to back and it dropped roughly 5'-7'.

shocksystems
09-10-2007, 11:55 AM
I designed a 30 by 60 garage. Two levels on a steep lot. We used a concrete plank to create the second story garage floor. The attic is an apartment.

Kellhammer: That place is beautiful. :bowdown: What part of the country is that as well? Cheers! Jim

kcclark
09-12-2007, 01:00 AM
You would not want to backfill against a pole building. But you could pour or lay block walls up high enough that it is out of the ground on all sides and then frame on top of that.

Been trying to avoid stick built this whole project but now I don't seem to have much choice.

Yotaforce
09-13-2007, 10:32 AM
Same problem I had. I had a hillside that would've required a 6-8' retaining wall to get a foundation. After finding out how much it would cost, I had a contractor with a dozer come out and he just took dirt off the highside and pushed it to the lowside. In the end, I had a bank of dirt only three feet high and a level area about 40x70 to build my 30x40 garage. Plus, it only cost about $100 per hour for the dozer work and it took him about 4 hours(between equipment failures) to finish it off.

kcclark
09-13-2007, 10:51 AM
Flattening things out isn't much of an option for me. Playing with the grade would run me into problems with the county because of drainage issues. Making the ground level would run me into problems with the township because they would make me shorten my proposed garage.