Building on a steep grade.

[shenders]

Hi. New here, great website.I have learned more in two days here than I have in years.
Does anyone have any pics and ideas about building a slab on a steep grade.The spot I have to use is level at the front,where the garage door will be and 40 feet back will take about 5 feet of bank run to bring it level with the front.The gravel is already in and level,but now I am having second thoughts about the height of the fill in the back.
Any pics of anyone elses build on a steep grade would sure help.

Thanks.

 

[twostory]

I am building a garage, 26ft wide, 44ft deep. My elevation drop is about 3.5 feet from the garage door back to the rear wall. I built footers and a stem wall. Then filled in the area under the slab with fill dirt, compacted every 4 inches with a (sheep's foot roller/********). I attached a picture of me during the fill doing some work.

If you need more detail, let me know.

Robert

 

[Tman]

I left the cut bigger on the west side of my place for a little BBQ area. Pics are in the Intro section.

 

[shenders]

Thanks, this is helping,please more pictures.

 

[Herb]

Hi. New here, great website.I have learned more in two days here than I have in years.
Does anyone have any pics and ideas about building a slab on a steep grade.The spot I have to use is level at the front,where the garage door will be and 40 feet back will take about 5 feet of bank run to bring it level with the front.The gravel is already in and level,but now I am having second thoughts about the height of the fill in the back.
Any pics of anyone elses build on a steep grade would sure help.

Thanks.

I had a similar situation, but my drop was 6 ft side to side. I didn't want to fill for (2) reasons. 1- Expense for good quality fill, 2- Even compacting at 4" lifts, I don't think it would ever be as stable as needed in my lifetime. My solution was to have a full drive in basement under my garage. 11 foot walls, 18'' Ibeam, 4''x9'' hemlock joists, and 3'' t&g hemlock flooring- 3 years and it hasn't fallen down yet.

 

[shenders]

Thanks Herb,I might chicken out but the gravel,150 tons is already in and leveled.Driver asked me what in the hell I was doing.Maybe a retaining wall at the back would help.
Thanks for the info so far.I have a huge gravel spot in the back yard and if I don't do something with it soon i'll be living on it.

 

[shenders]

Two Story thanks. More pics of the back would be great.

 

[twostory]

Re: Fill dirt cost

Yes fill dirt is expensive. I used 8 dump truck (18 tons) to fill under the slab area. That cost $2,000. The top load of gravel was $400. (1,000 square feet, 4 inches deep) I spent more on dirt and equipment rental than all the concrete cost to make my footer and 41 inch tall stem wall (25 yards)

As for compacting, Georgia is full of red clay. Clay will compact very nicely if the moisture content is right. I had good luck with the clay I had delivered, the vibrating roller would compact it easily. I passed the slab inspection today. I had to hire a "3rd party engineer" to check my dirt compaction. He said it is 2,000 psi or better.

If you look at my picture above, you will see the dirt is surrounded by the stem wall, so even if the dirt settles, it can not go anywhere. I do not expect much settling at all. I have the area covered in plastic right now, so rain water will not get into the fill dirt before I can pour the slab.

I am pouring the slab inside the stem wall and it will truely float on the dirt. The slab will not be attached to the stem wall anywhere. So if the dirt settles, the slab can move downward as a unit, and probably not crack much at all.

 

[twostory]

Two Story thanks. More pics of the back would be great.

Shenders,

I have more pictures on my home computer, but you can see a few pictures on our web site. I will post a "rear wall view" later tonight.

http://www.gtcreations.com/workshop/index.html

 

[shenders]

excellent pictures.Looks like a ton of work,literally.

 

[twostory]

Re: How many tons?

excellent pictures.Looks like a ton of work,literally.

I added up the weight (slow day at work)

25 yards concrete (2ton x 25 = 50 tons)
33 yards of broken up concrete from the old driveways (66 tons)
9 trucks of dirt/gravel (18ton x 9 = 162 tons)

Grand total = 278 tons of material have been moved to my new garage footprint.

I have another 17 yards of concrete for the slab (34 tons) and do not have a guess on how much the wooden two story structure will weigh (probably several tons).

 

[Donzi4me]

I have a 4' drop off from side to side. Poured a footer then put a 4' wall on top of that. Alot of fill inside and fill on the one side along with a retaing wall.

 

[PAToyota]

Shenders,

I have more pictures on my home computer, but you can see a few pictures on our web site. I will post a "rear wall view" later tonight.

http://www.gtcreations.com/workshop/index.html

Took awhile to make the connection, but I've read your wife's articles in Fine Woodworking! Nice work that she does! She is going to be up at the WoodWorks Show in York next month doing a couple classes - about 45 minutes south of me.