Replies

1. 
   jhausch | Nov 10, 2002 05:46pm | #1

   Hey Andy,

   I don't know what the soil is like in your area, but normally the lally's (since they are not subject to frost heave) only need to get to the firm stuff under the topsoil.  That being said, I would also add that the base of the lally should probably be 16" square and a minimum of 12" deep; put two layers of tic-tac-toe rebar in there, too.  The reason for a "minimum of 12" depth" is in case you are in an area with a very thin topsoil so you don't build them too thin.  Since you are in a basement, I am guessing that the topsoil doesn't make it that deep and you will be able to just dig out the hole, form it up, and go.  I recall a FHB article in the last couple of years that dealt with soil compaction, column supports vs. footers, etc.  I will 'dig' around for it.

   Steelkilt Lives!
1. 
   andybuildz | Nov 10, 2002 06:04pm | #2

   Jim

      Thanks. Thats what I thought which is why I said I was over doing it just to be safe with 18" wide and 18" deep. Rebar of course.

   Yeh...I'm abpoout six feet below the outside grade or better.

   BE well

          Namaste

                        AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

1. 
   Mongo | Nov 10, 2002 07:04pm | #3

   "Standard" lally footing for me is 24" sq, 12"deep. It allows a little lateral wiggle room.

   Set of plans I'm working on now specify 30" square, 12" deep footings, with three #5 bars in each direction, top and bottom. With the load above it's total overkill. All the columns are supporting is a single floor platform with no additional carried load from above.

1. 
   andybuildz | Nov 10, 2002 07:23pm | #4

   Mongo,

           I spose I dont understand the 24" wide part in my head....well, kinda do. I just thought that the depth was more important then the width being that the weight goes down. 12" depth to me just in my mind seems so shallow and fragile in spite of what everyone says. Knowing me at this point I'll end up going

   24x24X18. I just hate having to get all that dirt outta the basement in spackle buckets. My backs already killin' me just thinkin about it. Spose my back would hurt more if this old house came down on me after 322 years. It'd only figure.

   Thanks

   aIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

1. 
   calvin | Nov 10, 2002 07:38pm | #6

   Andy, we had to remove alot of dirt and debris from an old basement and found an electric conveyor got it through the window and into the bucket of a bobcat pretty easy.  Check your rentals.__________________________________________

   Remodeling Contractor just outside the Glass City.

   http://www.quittintime.com/

2. 
   brownbagg | Nov 10, 2002 07:28pm | #5

   let me reply as you was building here, different area has different variables.

   1) got to get below frost line.

   2) it depends on weight of whole house

   3) soil conditions

   4)concrete and rebar

    a good soil here will hold 2000 lbs per square inch, bearing wt.

   so by making the footing bigger and wider it will hold more weight with less pressure on soil.

   rebar does nothing buy keep concrete from bending, by more weight on top it will bend more.

   size of rebar does not matter it is total size of all steel in footing that matters.

   3 #4 or 2#6 basically the same. So figure how much weight, soil condions then how big of foting you can put in place. By pouring a stronger mix you can use less rebar. By using more rebar you can pour weaker concrete. By using more rebar, stronger concrete you can have a smaller footing. By having a bigger footing, stroner concrete and more rebar it will hold up more weigh so you can have a bigger safety factor. Just remember the weight of the concrete in the footing and the soil on top of the footing are also in the weight of the house.

1. 
   andybuildz | Nov 10, 2002 07:48pm | #7

   OK..heres the thing really. Besides the fact that I need a structural engineer. What I'm doing basically is just holding up the floor joists(trees) and the center bearing walls. The rubble rock is holding up the actual exterior walls (which is why I need a S.E). Thats another issue that I have not a clue about except through speculation around town here which aint worth much. I really need the S.E to look at the rubble rock foundation to tell me what to do with it and the plates above. The foundation actually appears to ME to look in good shape. I see no crumbling or rocks falling away from the wall.

    Bad earth pitch outside that needs correcting as well as better drainage outside. Need to keep the water away from the house which has been ignored for over half a century at least if you ask me. So far, the Historic Society says they'll get back to me to no avail. So where does the money they get go besides tours and tellin people what they CANT do? We'll see if they come through for me to a degree.

   Be well

           Namaste

                        AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

2. 
   Piffin | Nov 10, 2002 08:29pm | #8

   Haven't read the other posts becaus ethe wife is calling to go someplace.

   I just dig down 8-12" for something like this as long as it's solid ground. Then I tamp in a couple inches of inch minus sand-gravel mix to be firm and level. Then I roll in one of those concrete donuts you can buy precast about 18"diameter x 6or 8" deep. Post sits on it. I look to have the top of it flush with the ground so that if you pour a floor later, it wraps around the post and sits over the donut.

   Being close to the foundation wall, I would not dig too deep and you may not be able to use cookies or donuts but have to pour a hand mix.

   See you later.

   .

   Excellence is its own reward!

   "The first rule is to keep an untroubled spirit. The second is to look things in the face and know them for what they are." --Marcus Aurelius

1. 
   andybuildz | Nov 10, 2002 09:01pm | #9

   OK everyone....nuff said. gonna dig down 12" and do a 24" square with rebar double layered. Mix concrete and pour it......Thanks everyone.

   Be well

           Namaste'

                          AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

1. 
   r_ignacki | Nov 10, 2002 11:49pm | #10

   hey homeboy, why don't you just train those "tree floor joists" to grow branches down to the basement floor. Then you won't need no girder post looly pop colon holding them up.  lol  lol  listening for the secret.......searching for the sound...

1. 
   Nails | Nov 11, 2002 02:07am | #11

   p.r.   ............."looly pop colon"......Say What????? I'm going to the beer tavern and have one , with you in mind ,you poor confused soul.

2. 
   alias | Nov 11, 2002 06:24am | #12

   andy have used a system called the bigfoot system, have dug arather large hole to accomadate crushed blue stone and a lightweight plastic form that flares out at the bottom. have used them three times to shore up timber frame barns that were more than 40 lbs a square foot live load, with good results no stress cracks any where, and its been four years. i'm sure youve seen it in FHB. so give it a look see at f&s manufacturing in nova scotia the phone number is 1-800-934-0393, fax 902-275- 5704. i'll see if i have the web site in my file cabinet..... bear

3. 
   alias | Nov 11, 2002 06:33am | #13

   http://www.bigfootsystems.com pdf file also try http://www.strunet.com/concrete_beam, the later is a little work but helpful with a calculator, kinda enjoyed it ... good luck... bear

   Edited 11/10/2002 10:34:49 PM ET by the bear

   Edited 11/10/2002 10:35:24 PM ET by the bear

   Edited 11/10/2002 10:38:18 PM ET by the bear

1. 
   andybuildz | Nov 11, 2002 03:36pm | #14

   Bear,

           Couldnt open the second link. I tried typing it into my browser but that didnt work either. Thanks for the effort though. I thought about you when I started figuring my rubble rock foundation. Didnt you say you worked on it when you were in your early twenties? The actor that you said lived here from what I hear from my eccentric neighbor that you met I think said it was rented out in the summers, so that must be time you spoke about.

   Thanks again

                   AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

2. 
   andybuildz | Nov 11, 2002 03:53pm | #15

   Bear...One other thing. I think I'm going to do it the old fashon way.....dig...mix....and pour. I'm not really holding the exterior walls up, just basically the floor (trees) joists. After I do that I'm going to investiagte what to do with the soggy sole plates that ARE under the exterior walls. Thanks again

   aIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM

1. 
   GJR | Nov 11, 2002 05:32pm | #16

   BrownBagg,

       Is that correct   "a good soil here will hold 2000 lbs per square inch, bearing wt."    If that is the case then a 24"x24" footing would be capable of sustaining 576 tons!  What soil do you have,  bed rock? 

                                                        Regards,   Gary                                                 "Don't take life too seriously, you are not getting out of it alive"

2. 
   JohnSprung | Nov 11, 2002 11:23pm | #17

   > correct   "a good soil here will hold 2000 lbs per square inch,

   Probably he meant per square foot.  If not, the ground there is almost as hard as it is out here.  People backfill trenches with concrete mixed very very wet, because it's easier to dig out again....  

   -- J.S.

3. 
   brownbagg | Nov 12, 2002 03:54am | #19

   sorry, my mistake.  per square foot. i work with per square inch all day, it got me.

4. 
   GJR | Nov 12, 2002 04:09am | #20

   No problem and no need for an apology.  I thought you meant Sq Ft, but hey,  you never know!  Thought maybe you lived on the planet Jupiter :-)"Don't take life too seriously, you are not getting out of it alive"

3. 
   alias | Nov 12, 2002 01:21am | #18

   FWIW .......www.strunet.com...... the "old way" is really all you need to do with your house, start with some 3/4 blue stone 4-6 inches of that tamped, rebar four pieces banged in on corners stepped in 3-5 inches from forms. two layers of rebar depending on thickness of pad/footing 3-5" from bottom of form, 3-5" from top of form, wired to uprights, and a stiff pour take pad sander with pad taken off and run it around perimeter of form for 5 minutes to force air out and your done. a little overdone but i like taking that extra step.......but you know all this and i 've been explaining all day and i'm finished explaining today right know cheers bear