Garage pad- add on

[craigcd]

Allright i have done some searching on this topic and havent been able to come up with a answer. I am building a garage this spring and currently have a 22x20 pad poured by the builder.

I would like to extend the pad, and have poured concrete before(but never an extension). I am wondering if anyone has ever done this? Im sure i need to tie the new part into the existing pad, but im not sure how? Has anyone done this before?

Thanks

[97'Scort]

If you didn't leave rebar it's pretty hard to tie in. You can drill holes and grout in some rebar, but it's almost useless and the holes need to be about 3 feet in to be effective. You're better off grading and packing the new area well, and floating the new pad next to the one you poured.

I've seen the tie ins done, though, so I'd call a concrete company and see what they can offer.

[craigcd]

Originally posted by 97'Scort
If you didn't leave rebar it's pretty hard to tie in. You can drill holes and grout in some rebar, but it's almost useless and the holes need to be about 3 feet in to be effective. You're better off grading and packing the new area well, and floating the new pad next to the one you poured.

Yaa thats kinda what i figured, im just not sure if doing that would meet code. I have a call into the city (Aidrie) to see whats acceptable.

It has to be somewhat common i would think?

Craig

[ExtraSlow]

I guess it depends what you are using the extension of the pad for.
If it's for a parking pad beside your garage, then floating should be ok.

[97'Scort]

I chatted with a couple of the structural eng's at the office here, and they say there's a way to drill in and secure the rebar properly. You'd still have separation in the pads, though, and if one settles more than the other you could damage both of them. It's your call, but if you're fairly confident in the stability of the soil in your yard, then tying it it would be your best option.

[craigcd]

I am extending the existing pad to build a bigger garage. The builder poured the existing pad, and we are the second owners. I cant see why a seperate floating pad would a big deal, the ground is flat.

[97'Scort]

The problem is that if one of the pads, in, say, 10 years, settles farther than the other, it's going to cause damage to the structure attached to the top. Buildings have this problem where they don't like to bend very much

If you get a proper concrete company to come out and do the job and will warranty the construction, then go with whatever method they think will work better. If you're going to do it yourself, then soil, drainage, and packing prep is a lot more important than having flat ground.

Your third option, which you might want to consider if the costs are all coming in about the same, is to bust up the existing pad (especially if it's not on piles or a deep foundation) and pour a new one to your size.

[ExtraSlow]

Another option not mentioned is you could build the garage on new footings, and let the existing pad float inside of it.
That way, the structure of the building is solidly attached to one piece of concrete. if the slab in the middle settles or anything, it's not big deal to bust it up at that time and re-pour.

[barmanjay]

Originally posted by craigcd
I am extending the existing pad to build a bigger garage. ......

Make sure you check with city hall and see if you are allowed a bigger garage.

sizes are regulated.

you would definitely have to have new footing poured and rebar underpinned into the existing pad
Also before you think of it extending,.. and have the ok from city hall,.. have the local services come out and survey where the utils are.

If they run under where the new proposed pad will be, then you are SOL, you won't be allowed to construct.

[97'Scort]

Originally posted by ExtraSlow
Another option not mentioned is you could build the garage on new footings, and let the existing pad float inside of it.
That way, the structure of the building is solidly attached to one piece of concrete. if the slab in the middle settles or anything, it's not big deal to bust it up at that time and re-pour.

I like this idea too, but you'll have to sink piles to do it. Not bad though.

I'm going to dig up some pictures of the garage my dad and I did, I think there are a couple of people on here who will appreciate the engineering work in it

[ExtraSlow]

Originally posted by 97'Scort


I like this idea too, but you'll have to sink piles to do it. Not bad though.

I think piles would be overkill. Just your standard footer/pony wall setup would be plenty for almost any size of garage.

[Antonito]

Originally posted by ExtraSlow


I think piles would be overkill. Just your standard footer/pony wall setup would be plenty for almost any size of garage.

Hehe, then don't have an O&G engineer design a garage. A friend got an engineer to do one for him for free, and he spec'd 30 piles for a 2 car garage. My friend decided it was cheaper to pay regular rates to another engineer for a reasonable design

[barmanjay]

Originally posted by barmanjay


Make sure you check with city hall and see if you are allowed a bigger garage.

sizes are regulated.

you would definitely have to have new footing poured and rebar underpinned into the existing pad
Also before you think of it extending,.. and have the ok from city hall,.. have the local services come out and survey where the utils are.

If they run under where the new proposed pad will be, then you are SOL, you won't be allowed to construct.