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residential footer

29K views 20 replies 9 participants last post by  TimNJ  
#1 ·
Hey folks,

I have a question about how you guys do your residential footers. In Holmes County, there is no real code when it comes to residential building, with the exception of the septic plan, so now that I am building a house for my wife and I, some questions about the footer/foundation have come up.

the common footer size here for residential is 8" deep, 16" wide. What is it where you folks biuld?

Also, the print calls for the garage floor to be a minimum of 4" lower than the living quarters to avoid dangerous exhaust gases from creeping into the house. My question is, do I drop the footer 8" and add a block to keep wall height the same, or do I not add a block and use longer studs in the non-common garage walls?

What would you guys do?

Some info for perspective:
foundation: 3 courses of 8" with 1 course of 4x4x16 solids around perimeter
finished floor: 100'
finished garage floor: 99'8"
top of living area frost footer: 97'8"
top of garage area frost footer: 97'4"
 
#2 ·
There is no real code where we build most houses either (or should i say inspectors to inspec it) but we dig footings 12" deep and 24" wide and add 3 strands of #4 rebar 4" up from bottom on rebar chairs.Crossing and tieing at corners. I think we started doing that just cause our backhoe guy only had 1' and 2' buckets and 1' deep just sounds like a good number not to mention easy to figure concrete. I usually figure my crete at 26" wide cause the buckets teeth stick out a little. As for the garage we use longer studs, but our houses are allways on crawl space so the garage will be 3-4 steps down anyway with a 10- 12' ceiling.
 
#3 ·
footers

In NY our footers have to be 42" below grade If i was building on slab I would dig down in the front of the garage to 42" deep 16" wide for 8" block Then i like to pour the footer up about 18 "in the trench and start blocking from there because it hard to lay block down in the hole so deep.If there where only 3 rows of block i would make the walls even on top for framing.On a slab i would use shoe block for the liveing space and 8x8x16 cap blocks in the garage area .The garage floor gets poured inside the block walls .Our footings are allways twice the size of the block 8" block 16" footer 10" block 20" footer I use a 20" footer most of the time because my track hoe has a 20" bucket. We run 2 5/8 rebar around the footer. My floor are 4" thick with 6x6 wire and a 6 mil plastic. Our wood has to be a min of 8" out of the ground .If you had a wood floor the blocks would be the same hight and the wall studs would be lounger in the garage. I would think its cold in ohio and your footers would need to be be deeper .
 
#4 · (Edited)
I forgot to mention. Say the ground is level and the house has 4 rows the garage will have 1 or 2 rows ( depending on how high the drive will be) plus a row of form block. Then pour the garage floor and build on top of that. I just seems easier to me to pour the slab first. It also gives a nice clean and level place to work too. The wood will be more than 8" from ground and the outside is usually bricked up to the level of the house floor if not all the way up. Counting a floor thickness of about 1' there will be 3 or 4 steps down to garage floor.

I also think the frost line is a concern in your area. No such thing here.
 
#5 ·
IEven if you do not have a code, look at the International Resisential Code (2006 IRC) for foundation construction. It is a good, reasonable prescriptive standard to use as a guide. It is unfortunate that you do not have a code official or inspector to lean on for advice.

As far as the depth to the bottom of the footings, call and advacent area to see what the requirements are there. Mother Nature is usually pretty consistant if you do not stry to far. If you have a choice, pick and area north of you since not being deep enough is major mistake that can cost a fortune to correct.

For footing size, 8" thick is usually adequate and reinforcement is not required in some places. Some people use a 12" thick footing. For width, the 8" footing should he 8" wider (4" on each side onf the wall) than the wall thickness. Around here, more contractors automatically use 20" wide since the foundation wall thickness could change or the footing layout may not be perfect when it comes to the walls. This makes it easier to give the wood butchers a squre place to start. All footings here are formed.

Here, most garages are built using higher (about 8" max) block stem walls so the slab can be a floating slab poured between the stem walls and can be poured later for drainage slopes and still have level foundation wall heights and keep the garage floor below the house floor. - It also makes for an easier to clean floor that will not cause the plate and studs to rot. Normal stud lengths (or more) are used to give more valuable headroom or a higher door.
 
#7 ·
We're only required to go 16"X8" deep
for up to two stories, no bars.
A mile of ice packed our clay
down pretty well.
I always dig with a 2' bucket though,
a little over kill and a little wiggle room.
I run the block level all around (usually)
and pour down 4" in the garage.
Stop the drywall at the bottom of the
sole plate, like concretemasonry says,
can hose it down and not hurt the d/w.
Haven't done a slab house in a ****'s age,
so it winds up @15½" slab to subfloor.
 
#9 ·
I hear what you guys are saying. This is exactly what I had planned to do, but if I do that, I will not be below frost with the bottom of my footer around the perimeter of the garage.

The plan is 3 rows of 8" with a row of 4x4 solids to be the form for the slab for the living area. For the garage, I almost think I need to go 4 rows of 8", so I would have to drop the footer by 4" to keep a common foundation height. I have been thinking, and if I do this, my stud lengths will different anyway, because all the walls on the slab will be regular walls with ACQ bottom plate, studs, and double top plate. In the garage area, we will need a 2x8 ACQ sill plate, with the walls built on top of that, making the studs 1.5" shorter.

I'm thinking in circles here...I just want to make this as simple as possible for the framers. I wish I could put a drawing of this in here.
 
#10 ·
In Lubbock everything is 12" deep and 12" wide. Two rows of #4 bar set on bricks or chairs. 48" bypass on all rebar joints. Then they monolithic pour slab and footings. Garage is 8" lower than slab. In Kansas it's 24" deep minimum, and 10" wide. You will never see a block used. Way too much labor. Engineered floor trusses sith on pressure treated plate bolted to the foundation wall.
 
#13 ·
Hey Dutch, surely your frost line
is at least 32", which means three
courses in the ground, and
you want at least 6"-8" from
grade to frame.
That's 4 full courses all round.

BTW: I just realized where you
are, I have an aunt in
New Philadelphia.
My Dad use to love visiting
with an old wood carver in
Dover, maybe his little museum
is still there.
His name will come
to me by and by.
 
#14 ·
Hey Dutch, surely your frost line
is at least 32", which means three
courses in the ground, and
you want at least 6"-8" from
grade to frame.
That's 4 full courses all round.

BTW: I just realized where you
are, I have an aunt in
New Philadelphia.
My Dad use to love visiting
with an old wood carver in
Dover, maybe his little museum
is still there.
His name will come
to me by and by.
Hey Neo,

I am not trying to make this difficult, I am trying to make it as simple as possible. If it means adding another course of block, I would gladly do that. What is making this difficult is the whole slab thing. I want the foundation to be a common height in the living area and garage, and using the 4x4 solids as a form for the living area is the source of this dilema. I am now thinking about going 4 rows of 8" for the living area, with the 4x4 solids on top of that as a form. Then I will use 5 rows of 8" for the garage. the new elevations would be:

living area finished floor: 100'
garage finished floor: 99'8"
final grade outside: 99'4"
top of footer for living area: 97'
top of footer for garage: 96'8"

footer is 8" deep and 16" wide. This would give me 8" above final grade to start the framing. Does this sound better?

BTW, that old school carver from New Philly was named Mooney Warther. :thumbsup:
 
#17 ·
Tell me if I am beating a dead horse here.
I'm starting to think that the term "ell block"
doesn't translate across state lines,
might be local lingo?

This place calls them, "8X8X16 Solid Header Pier"
http://www.cinderblockonline.com/graphics/grayblock_8.gif
(second row from the left, fourth one down)

The beauty of these is that with the ledge
turned out you can run foam insulation
all the way to the top of the block,
thereby creating a complete thermal break.
If you use 2X6 studs the sole plate
will bridge the block and the foam completely.



Thanks for the info about Warther,
and yes I've got a regular pair
and one of the triples, both signed.
I went on and dug 'em up anyway.
Got to admit though, Dad's are more special.
 
#21 ·
Also, the print calls for the garage floor to be a minimum of 4" lower than the living quarters to avoid dangerous exhaust gases from creeping into the house.
I never heard of that one. Is CO a heavy gas that settles low?

This is what I understand the reason for the step and the downslope to the garage door. If a car ever develops a gas tank leak or if somebody spills a gas can, or other flammable liquid for that matter, if there was no step in the floor level of the living space vs garage space the flammable liquid would run under your wall and into the living space. Second reason for anybody in snow country, when you pull into the garage and your car has a ton of snow packed on it and it melts, you don't want all that water running under your walls and doors into your living space either.