Footing Questions

[icmaster]

I'm a do- it- yourselfer, trying to build my first house myself. I am working on my forms for my footings right now. The inspector told me to use metal grade pins. I bought what the building supply store called metal grade pins- 18 in rebar. How are they supposed to be used?
I've used a laser - shooting the middle of the footing and setting the grade pins where the laser beam hits the top of the grade pin(at 12 inches). I have set my forms to the same level. Also, the top of the footing at one end of the house will be 7 inches above grade. Is this acceptable - according to 1999 Southern Building Code- what our county uses?

[Rich]

Try this article for a basic outline of what is involved with your footer.
http://www.construction-resource.com/articles/concrete_footing.html
I think the reference to metal grade pins are what I call form stakes. I've used grade pins before but never for a footing... I used them to outline a valley in a floor slab so I didn't miss the change in slope. Form stakes are smooth pieces of 3/4" metal with holes through the center. They work by pounding them in along the outside of the form and then using the laser to shoot the top of the form in at the level desired. When you get it where it's supposed to be you use the holes in the form stakes to nail through the stake into the form (8d duplex nails work best).
7" out of the ground doesn't seem right. Of course when you're building in Montana everything is 38-48" deep to be below frostline. But since you're in the south where there are quite a few slab on grades you might be alright with that. Make a call into your building inspector - they should be able to help you out as far as local code requirements.
Hope that helps.
Oh.. and welcome to the forum..

[icmaster]

I am still digging my footings, and after shooting it with my laser, I have to dig deeper to keep the top of the footings at grade level. The county requires 12inch thick footings by 18inches wide, but in some portions of the footings I hit solid rock where I will not be able to go down 12 inches, though the footing would be resting on solid rock. Do you know of anyone that has encountered this problem? What is done about it, if anything? The only other option I see to keep the 12 inches, will put my footing 7inches above grade on one end of the house.
Thanks for the welcome to the forum- this is a great idea.

[Rich]

There are typically stipulations in the code that has some language as to bearing on solid rock. I would say if you had 4 inches or more you would be ok... and as long as it's not for too long of a distance.