strong concrete block walls - Page 3

> Former Hoosier. 36" should be good for that area.
> I wouldn't pour a footing for a doghouse without a
> couple #4 rebar's in it.

> wrote:
>> Former Hoosier. 36" should be good for that area.
>> I wouldn't pour a footing for a doghouse without a
>> couple #4 rebar's in it.
> Well, that's pretty interesting considering who's
> saying it. You're
> an old timer and you often point out about the
> benefits of old time
> construction. They didn't use rebar in footings for
> generations, so
> what's happened to the soil recently that it's now
> required in every
> situation? Right, nothing.
> Code is an attempt to create a one-size-fits-all
> building. If a
> builder knows what they're doing, and take into
> account local
> conditions and compensates for them, there is no need
> for rebar. If
> Code calls for it, well, you have no choice and you
> have to put it
> in. That doesn't mean that the rebar actually adds
> any benefit and it
> does not compensate for poor foundation practices.
> R

> > Hello, I will build a concrete block wall 4 blocks high for a garage.
> > Three of the courses will be below grade. I want to make this wall as
> > strong as practically possible. (I could not use a poured wall because of
> > access problems). I live in a freeze/thaw area. I want to use some rebar
> > in the cores for strength. Should these cores with rebar be filled with
> > concrete or mortar? Also anything I can do to prevent cracking from the
> > freeze/thaw cycles? Would a control joint on each wall make sense?
> Basically I don't want the wall to crack. It will sit on a 8 x 16 footer at
> the frost line. The wall will be 4 blocks high with 3 below ground. My
> concern was could expansion/contraction from freezing/thawing crack the
> wall? And if so, is there anything I can do to prevent this?
> I'm not sure this would normally happen, so maybe it's not a problem, but
> since I don't know I sent the post. I will use the rebar in the footer and
> at 4' as DanG suggested.

>> > Hello, I will build a concrete block wall 4 blocks high for a
>> > garage.
>> > Three of the courses will be below grade. I want to make
>> > this wall as
>> > strong as practically possible. (I could not use a poured
>> > wall because of
>> > access problems). I live in a freeze/thaw area. I want to
>> > use some rebar
>> > in the cores for strength. Should these cores with rebar be
>> > filled with
>> > concrete or mortar? Also anything I can do to prevent
>> > cracking from the
>> > freeze/thaw cycles? Would a control joint on each wall make
>> > sense?
>> Basically I don't want the wall to crack. It will sit on a 8 x
>> 16 footer at
>> the frost line. The wall will be 4 blocks high with 3 below
>> ground. My
>> concern was could expansion/contraction from freezing/thawing
>> crack the
>> wall? And if so, is there anything I can do to prevent this?
>> I'm not sure this would normally happen, so maybe it's not a
>> problem, but
>> since I don't know I sent the post. I will use the rebar in
>> the footer and
>> at 4' as DanG suggested.
> I just did a quick check on frost line depth in Indiana, and
> depending
> on where you are, it can vary from 30" to 42". The first thing
> you
> should do is verify the frost line design criteria.
> The buried portion of the foundation does not usually have a big
> problem with freeze/thaw. If you're garage is unheated and
> there's
> soil on both sides of the foundation, there's almost no chance
> of a
> problem. Freeze/thaw
> only becomes an issue if there is a fair amount of water in the
> soil.
> While you are excavating your foundation, you should determine
> what
> sort of soil you have and it's drainage capabilities. If there
> are
> any doubts, you can put in drainage tile (not actually tile,
> it's
> really pipe) around the perimeter, and/or use gravel and sand in
> the
> backfill.
> Rebar in footings is unnecessary unless you have doubts about
> your
> soil or if your subgrade preparations are faulty. A couple
> pieces of
> rebar won't make the footing act like a beam, it will just keep
> the
> pieces together, and, frankly, it's extremely rare for different
> sections of a footing/foundation to have any appreciable
> differential
> settlement unless the soil conditions and drainage are poor, or
> your
> subgrade preparations are faulty.
> I guess you catch my drift by this point. If you don't take
> into
> account the soil conditions, drainage and subgrade preparations,
> any
> work you do after that will be at risk. 'Superior' construction
> won't
> negate those failures.
> R