[xjxt]

How to form slope in a 24'x34' garage slab

Hello to all
It's been many years since I last visited and posted a question on this forum at the time I was doing a total rehab on my current home,approx. 2011
At this point I'm in the planning stages of building a new 24x34' detached garage and I found several posts on this forum in regards to the different methods in how to set concrete forms to create slope in a garage concrete slab.
In one post I found was by a member who's user name (if I remember correctly) is ,"jomama45" he gave an explanation on how he uses a 2x4 to create this slope from the rear of the garage to the front of the garage with out having to rip the inner form board length wise to form the slope. I read it several times but I'm still having a hard time picturing exactly how he sets this up.

 

[dj3]

String a line from the back end to the front with a 1/8" per foot slope. Then frame it following the line.
Example: if your pad is 10 ft deep, the rear end of your form should be 1-1/4" higher than the opening. Do the same thing on the other side. Then grade to fit.

 

[Nealtw]

I would just put the slope in the form and then use a laser level to measure the studs to fit so the top of the wall is level.

 

[SeniorSitizen]

Have you considered this method of wall framing then slope the compacted gravel / soil the amount of slope you want the floor. This will automatically provide you forms on 3 sides. Even concrete block stem walls have been real common for a long time and do well when done right on a good footing.

 

[ddawg16]

You didn't say where you are. Do you have to deal with a frost line?

I'm personally a fan of stem walls. My stem wall sticks up 8" from the slab. This gets the base of my wall well above grade thus reducing the chance of water ingress.

As for slope? I have 2" from front to back. It's way to much. I wish I had gone with 1/2" at most.....or no slope at all. The only time I have any water in my garage is if I'm washing it out.

Look at the garage build link in my signature for some pics.

 

[xjxt]

A big Thank you for all your replies.
ddawg16,I'm also located in So.Cal. in Claremont.
I took a look at the link you provided of your 2 story garage build .WOW, that is absolutely awesome work.I'm only looking to build a simple single story 24x34' garage. My existing attached garage was built with a short stem wall approx. 6" tall but it was built using blocks with the cells filled with grout or concrete as SeniorSitizen described, it was built in the '60's, I've always seen stem walls in all new construction.
So getting back to my original question I wonder if having slope is really neccessary or required by code
Another question I have, is pouring a footing with blocks set on top and pouring the slab last? I wonder what the cost difference is compared to a monolithic type?

 

[Nealtw]

If you are building a work shop, you don't need a slope but you want the apron out side to have a 1% grade away from the door.

The only reason we do a stem wall is for frost depth, you can form up and put a curb on a flat or sloped slab.

 

[Old Thomas]

My shop is 36x48. The back half (24’) is flat, the front half slopes to a drain.