I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Thanks,
Dave

On Jun 25, 12:33 am, headware wrote:
I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

There's no need to attach the patio slab to the house. Slabs don't
slide unless you did something seriously wrong, like build it on a
hillside. The patio slab should not move appreciably, if at all, if
you prepare the sub-grade soil correctly, add aggregate as required
for drainage, and compact it.

R

On Jun 25, 12:33 am, headware wrote:
I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Thanks,
Dave

determine soil type, drainage now and after, and whether the earth has
been disturbed in recent years.
in a climate that includes winter, and if needed by soil type,
foundation footers of concrete may be used to a depth specified to
below the frost line. if this is a warm climate beach house or pole
house on sandy soil there may be a different local answer. make
specific plans for rain drainage as needed by your climate. thickness
of concrete and its future use as an enclosed part of the home may
help determine its construction, such as an insulated slab
requirement.
your local building inspector may have plenty of experience with all
your local factors and that helps you to do it right the first time.
its size and placement and setbacks on your lot are best determined
with him.
see also:
http://www.buildingscienceconsulting...r_Renovate.pdf

"buffalobill" wrote in message
ps.com...
On Jun 25, 12:33 am, headware wrote:
I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Thanks,
Dave

determine soil type, drainage now and after, and whether the earth has
been disturbed in recent years.
in a climate that includes winter, and if needed by soil type,
foundation footers of concrete may be used to a depth specified to
below the frost line. if this is a warm climate beach house or pole
house on sandy soil there may be a different local answer. make
specific plans for rain drainage as needed by your climate. thickness
of concrete and its future use as an enclosed part of the home may
help determine its construction, such as an insulated slab
requirement.
your local building inspector may have plenty of experience with all
your local factors and that helps you to do it right the first time.
its size and placement and setbacks on your lot are best determined
with him.
see also:
http://www.buildingscienceconsulting...r_Renovate.pdf


Down in Palm Beach County, Florida the rebar is a 'must'. The County would
not approve the permit unless you drilled the rebar into the existing slab.

On Jun 25, 7:33 am, "jerryl" wrote:

Down in Palm Beach County, Florida the rebar is a 'must'. The County would
not approve the permit unless you drilled the rebar into the existing slab.

Interesting. What's the reasoning?

If the patio base is prepared correctly dowel pins don't do any work
at all. If the base is not prepared correctly the dowels will be
called on to do all of the work, which will almost assuredly lead to
the top of the slab spalling above the dowels.

Code requires three inches of concrete cover around rebar for ground
contact slabs. So FL requires a 6" patio slab?

Makes no sense.

R

On Jun 25, 1:45 am, RicodJour wrote:
On Jun 25, 12:33 am, headware wrote:

I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

There's no need to attach the patio slab to the house. Slabs don't
slide unless you did something seriously wrong, like build it on a
hillside. The patio slab should not move appreciably, if at all, if
you prepare the sub-grade soil correctly, add aggregate as required
for drainage, and compact it.

R

Rico, attachment is common "upstate" to prevent migration caused by
front heaves -- esp. since most patios are floating and don't have
footers to keep them in place.

Another way to do it, is to interlock to big eye bolts (no one said it
was easy) and to put on into the wall and one into the slab (tacked
onto the screen or the rebar) with the "joint" at the border of the
two pieces (in the felt expansion pad) so that the slab can float up
and down without drifting away.

On Jun 25, 10:27 am, Pat wrote:

Rico, attachment is common "upstate" to prevent migration caused by
front heaves -- esp. since most patios are floating and don't have
footers to keep them in place.

Another way to do it, is to interlock to big eye bolts (no one said it
was easy) and to put on into the wall and one into the slab (tacked
onto the screen or the rebar) with the "joint" at the border of the
two pieces (in the felt expansion pad) so that the slab can float up
and down without drifting away.

I know it's common, so is questionable construction. The dowels are
silly.

Frost heave is only a concern if there's a chance that the sub-grade
structure will be levered/ratcheted up with repeated freeze-thaw
cycles. There is exactly zero chance of a slab being racheted upwards
as there is nothing sub-grade for the freeze-thaw to work against.
The slab floats on top.

The only thing you have to worry about is the tiny amount of
differential movement between the house and slab, and you pointed out
one way to deal with that.

R

On Jun 25, 10:50 am, RicodJour wrote:
On Jun 25, 10:27 am, Pat wrote:



Rico, attachment is common "upstate" to prevent migration caused by
front heaves -- esp. since most patios are floating and don't have
footers to keep them in place.

Another way to do it, is to interlock to big eye bolts (no one said it
was easy) and to put on into the wall and one into the slab (tacked
onto the screen or the rebar) with the "joint" at the border of the
two pieces (in the felt expansion pad) so that the slab can float up
and down without drifting away.

I know it's common, so is questionable construction. The dowels are
silly.

Frost heave is only a concern if there's a chance that the sub-grade
structure will be levered/ratcheted up with repeated freeze-thaw
cycles. There is exactly zero chance of a slab being racheted upwards
as there is nothing sub-grade for the freeze-thaw to work against.
The slab floats on top.

The only thing you have to worry about is the tiny amount of
differential movement between the house and slab, and you pointed out
one way to deal with that.

I just realized that I wasn't clear about something. The expansion
joint material is all you need, not dowels or eye-bolts or anything
else.

The same way that Bob Morrison (hope you're doing well, Bob!) sees
little if any benefit in placing wire mesh in a concrete slab, I see
no benefit in using dowels in an attempt to compensate for proper sub-
grade preparation.

R

On Jun 25, 7:01 am, RicodJour wrote:
On Jun 25, 10:50 am, RicodJour wrote:



On Jun 25, 10:27 am, Pat wrote:

Rico, attachment is common "upstate" to prevent migration caused by
front heaves -- esp. since most patios are floating and don't have
footers to keep them in place.

Another way to do it, is to interlock to big eye bolts (no one said it
was easy) and to put on into the wall and one into the slab (tacked
onto the screen or the rebar) with the "joint" at the border of the
two pieces (in the felt expansion pad) so that the slab can float up
and down without drifting away.

I know it's common, so is questionable construction. The dowels are
silly.

Frost heave is only a concern if there's a chance that the sub-grade
structure will be levered/ratcheted up with repeated freeze-thaw
cycles. There is exactly zero chance of a slab being racheted upwards
as there is nothing sub-grade for the freeze-thaw to work against.
The slab floats on top.

The only thing you have to worry about is the tiny amount of
differential movement between the house and slab, and you pointed out
one way to deal with that.

I just realized that I wasn't clear about something. The expansion
joint material is all you need, not dowels or eye-bolts or anything
else.

The same way that Bob Morrison (hope you're doing well, Bob!) sees
little if any benefit in placing wire mesh in a concrete slab, I see
no benefit in using dowels in an attempt to compensate for proper sub-
grade preparation.

R

We pour 500+ patios, driveways, etc. a year in Southern CA. Some soils
engineers require 'dowels' to be installed on any concrete flatwork
that adjoins to the foundation. In my experience this is a waste of
time and money. 90% of problems with concrete flatwork occur when the
sub-grade is not properly compacted or pre-saturated in highly
expansive soil. The other 10% of problems come from incorrect joint
placement,improper finishing and rarely bad concrete. Just my 2 cents.

On Sun, 24 Jun 2007 21:33:39 -0700, headware
wrote:

I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

We just had a thread about stoops or front porches that sink, and one
person, I don't remember who, said to put in rebar to keep the stoop
from sinking.

This sounds similar, fwiw.


Thanks,
Dave

On Mon, 25 Jun 2007 08:01:35 -0700, RicodJour
wrote:



The same way that Bob Morrison (hope you're doing well, Bob!) sees
little if any benefit in placing wire mesh in a concrete slab, I see
no benefit in using dowels in an attempt to compensate for proper sub-
grade preparation.

Now I'm confused. Despite Bob's attitude, a lot of people do place
wire mesh in concrete slabs. Maybe even you. By comparing** Bob's
opinion there to your own here, it makes it seem like it would be
prudent to put in the bars.

**Bob says little if any benefit. You say flatly no benefit, but
still similar.

R

On Jun 25, 5:36 pm, mm wrote:
On Mon, 25 Jun 2007 08:01:35 -0700, RicodJour

wrote:

The same way that Bob Morrison (hope you're doing well, Bob!) sees
little if any benefit in placing wire mesh in a concrete slab, I see
no benefit in using dowels in an attempt to compensate for proper sub-
grade preparation.

Now I'm confused. Despite Bob's attitude, a lot of people do place
wire mesh in concrete slabs. Maybe even you. By comparing** Bob's
opinion there to your own here, it makes it seem like it would be
prudent to put in the bars.

**Bob says little if any benefit. You say flatly no benefit, but
still similar.

You're right, it does seem that you're confused.
Bob believes that mesh in a slab is a waste of money and time - I
agree with him.
The effort and expense can be put to better use dealing with where the
problems start, the sub-grade preparation.
Same with the dowels.
I'm not trying to put words in Bob's mouth. I don't remember him
weighing in on this particular aspect but the approach is very
similar.

R

headware wrote:
I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Thanks,
Dave

I don't know concrete, but what you are suggesting sounds like a bad
idea to me, especially if you live in an area with deep freezes. My
reason is that with some heave from freezing you could end up with the
patio slanted toward the house and have problems with water and/or ice.
If not properly done, it might even expand enough to crack foundation
or do something else weird.

"headware" wrote in message
ups.com...
I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Oh, hell no. If the patio frost heaves, it'll crack the foundation.
Horizontal movement isn't the problem- up and down movement is. 2nd big
problem, especially if patio does frost heave, is water on patio ponding
near house, draining in the crack where it meets foundation, and flooding
basement. (I have a small dose of that here, with an abandoned patio buried
under a 18" tall deck. No way to fix without tearing out deck.)

So, you want patio to have the classic 1/4" per foot slope away from house,
you want yard past that to keep sloping, you want good flashing on house
side where it meets the patio (and never pour concrete so it buries the
siding), and maybe just for laughs a drain tile on house side of patio,
going to daylight or a collector box. A good roof overhang or awning helps,
too. Patio itself needs footings, either traditional or a monolithic pour
based on shape of the hole and the fabric and rebar. Any good concrete
flatwork company will understand, and do what is appropriate for local
climate and soil conditions.

aem sends....

On Mon, 25 Jun 2007 14:55:34 -0700, RicodJour
wrote:

On Jun 25, 5:36 pm, mm wrote:
On Mon, 25 Jun 2007 08:01:35 -0700, RicodJour

wrote:

The same way that Bob Morrison (hope you're doing well, Bob!) sees
little if any benefit in placing wire mesh in a concrete slab, I see
no benefit in using dowels in an attempt to compensate for proper sub-
grade preparation.

Now I'm confused. Despite Bob's attitude, a lot of people do place
wire mesh in concrete slabs. Maybe even you. By comparing** Bob's
opinion there to your own here, it makes it seem like it would be
prudent to put in the bars.

**Bob says little if any benefit. You say flatly no benefit, but
still similar.

You're right, it does seem that you're confused.

Hey, I've been confused by less complicated things than this!

Bob believes that mesh in a slab is a waste of money and time - I
agree with him.
The effort and expense can be put to better use dealing with where the
problems start, the sub-grade preparation.
Same with the dowels.
I'm not trying to put words in Bob's mouth. I don't remember him
weighing in on this particular aspect but the approach is very
similar.

R

On Jun 25, 7:18 pm, "aemeijers" wrote:
"headware" wrote in message

ups.com... I'm planning on pouring a concrete patio up against my house in the
back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Oh, hell no. If the patio frost heaves, it'll crack the foundation.
Horizontal movement isn't the problem- up and down movement is. 2nd big
problem, especially if patio does frost heave, is water on patio ponding
near house, draining in the crack where it meets foundation, and flooding
basement. (I have a small dose of that here, with an abandoned patio buried
under a 18" tall deck. No way to fix without tearing out deck.)

So, you want patio to have the classic 1/4" per foot slope away from house,
you want yard past that to keep sloping, you want good flashing on house
side where it meets the patio (and never pour concrete so it buries the
siding), and maybe just for laughs a drain tile on house side of patio,
going to daylight or a collector box. A good roof overhang or awning helps,
too. Patio itself needs footings, either traditional or a monolithic pour
based on shape of the hole and the fabric and rebar. Any good concrete
flatwork company will understand, and do what is appropriate for local
climate and soil conditions.

aem sends....

So it sounds like this might be a really bad thing to do. I live in
Austin, TX where we do occasionally have pretty serious (but brief)
freezes, but I don't know how much they affect the soil.

My yard is on a slight slope with the back (where the patio is going)
being higher than the front. I am planning on sloping the patio away
from the house with the end running into a dry creek bed that will
serve as drainage.

I guess I'll just have to see what the building inspector has to say
about it.

Thanks for all the help.

Dave

headware wrote:
On Jun 25, 7:18 pm, "aemeijers" wrote:

"headware" wrote in message

roups.com... I'm planning on pouring a concrete patio up against my house in the

back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Oh, hell no. If the patio frost heaves, it'll crack the foundation.
Horizontal movement isn't the problem- up and down movement is. 2nd big
problem, especially if patio does frost heave, is water on patio ponding
near house, draining in the crack where it meets foundation, and flooding
basement. (I have a small dose of that here, with an abandoned patio buried
under a 18" tall deck. No way to fix without tearing out deck.)

So, you want patio to have the classic 1/4" per foot slope away from house,
you want yard past that to keep sloping, you want good flashing on house
side where it meets the patio (and never pour concrete so it buries the
siding), and maybe just for laughs a drain tile on house side of patio,
going to daylight or a collector box. A good roof overhang or awning helps,
too. Patio itself needs footings, either traditional or a monolithic pour
based on shape of the hole and the fabric and rebar. Any good concrete
flatwork company will understand, and do what is appropriate for local
climate and soil conditions.

aem sends....


So it sounds like this might be a really bad thing to do. I live in
Austin, TX where we do occasionally have pretty serious (but brief)
freezes, but I don't know how much they affect the soil.

My yard is on a slight slope with the back (where the patio is going)
being higher than the front. I am planning on sloping the patio away
from the house with the end running into a dry creek bed that will
serve as drainage.

I guess I'll just have to see what the building inspector has to say
about it.

Thanks for all the help.

Dave


Hey, if you are here in Central Texas, you should pay
attention to this. I have only done 50 or so new slabs
against old slabs, but they have all been engineered. In
every instance, the engineer specified dowels into existing
concrete, spacing, etc. I always do this here as I have had
to remove 3 slabs (not mine) that have move away from the old
foundation enough that it caused problems.

I know that many of the people in here are against dowels and
some are against rebar at all. I have been working in this
area for about 30 years and I have never seen anything but 2nd
story patio slabs (lightweight concrete, 2" thick) poured
without rebar. And I have never seen a slab connection that
did not have dowels.

I have never had an engineer that is familiar with the soils
in this area spec anything but dowels and rebar for new
against existing. The soils in this area demand it.

--
Robert Allison
Rimshot, Inc.
Georgetown, TX

"Robert Allison" wrote in message
news:nZAhi.258$bO2.83@trnddc05...
headware wrote:
On Jun 25, 7:18 pm, "aemeijers" wrote:

"headware" wrote in message

groups.com... I'm
planning on pouring a concrete patio up against my house in the

back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Oh, hell no. If the patio frost heaves, it'll crack the foundation.
Horizontal movement isn't the problem- up and down movement is. 2nd big
problem, especially if patio does frost heave, is water on patio ponding
near house, draining in the crack where it meets foundation, and flooding
basement. (I have a small dose of that here, with an abandoned patio
buried
under a 18" tall deck. No way to fix without tearing out deck.)

So, you want patio to have the classic 1/4" per foot slope away from
house,
you want yard past that to keep sloping, you want good flashing on house
side where it meets the patio (and never pour concrete so it buries the
siding), and maybe just for laughs a drain tile on house side of patio,
going to daylight or a collector box. A good roof overhang or awning
helps,
too. Patio itself needs footings, either traditional or a monolithic pour
based on shape of the hole and the fabric and rebar. Any good concrete
flatwork company will understand, and do what is appropriate for local
climate and soil conditions.

aem sends....


So it sounds like this might be a really bad thing to do. I live in
Austin, TX where we do occasionally have pretty serious (but brief)
freezes, but I don't know how much they affect the soil.

My yard is on a slight slope with the back (where the patio is going)
being higher than the front. I am planning on sloping the patio away
from the house with the end running into a dry creek bed that will
serve as drainage.

I guess I'll just have to see what the building inspector has to say
about it.

Thanks for all the help.

Dave


Hey, if you are here in Central Texas, you should pay attention to this.
I have only done 50 or so new slabs against old slabs, but they have all
been engineered. In every instance, the engineer specified dowels into
existing concrete, spacing, etc. I always do this here as I have had to
remove 3 slabs (not mine) that have move away from the old foundation
enough that it caused problems.

I know that many of the people in here are against dowels and some are
against rebar at all. I have been working in this area for about 30 years
and I have never seen anything but 2nd story patio slabs (lightweight
concrete, 2" thick) poured without rebar. And I have never seen a slab
connection that did not have dowels.

I have never had an engineer that is familiar with the soils in this area
spec anything but dowels and rebar for new against existing. The soils in
this area demand it.

Okay, backpedal time for me- I slid right over where OP said 'slab' in his
original post, nor did I know he was in Texas with their notorious funny
soils and moisture control problems. What I said is true for 'up north'
basement/crawl construction with block or poured walls, and frostlines that
are actually below ground leverl. Slabs on clay, especially pretensioned
ones, are pretty much outside my realm of experience. If the house is built
on an itty-bitty runway, as it were, that is probably a whole different
section of the how-to book, and one I haven't read.

aem sends...

On Jun 30, 5:40 pm, Robert Allison wrote:
headware wrote:
On Jun 25, 7:18 pm, "aemeijers" wrote:

"headware" wrote in message

roups.com... I'm planning on pouring a concrete patio up against my house in the

back yard. A friend of mine has suggested that I drill holes into the
side of the house foundation and plug rebar into them so when the
patio is poured it will be "attached" to the house slab via the rebar.
He says this is necessary to prevent the patio slab from sliding away
from the house after it begins settling. I'm a total novice, but none
of the books I've seen have mentioned this issue. Is he making up
problems or is this something I should take seriously?

Oh, hell no. If the patio frost heaves, it'll crack the foundation.
Horizontal movement isn't the problem- up and down movement is. 2nd big
problem, especially if patio does frost heave, is water on patio ponding
near house, draining in the crack where it meets foundation, and flooding
basement. (I have a small dose of that here, with an abandoned patio buried
under a 18" tall deck. No way to fix without tearing out deck.)

So, you want patio to have the classic 1/4" per foot slope away from house,
you want yard past that to keep sloping, you want good flashing on house
side where it meets the patio (and never pour concrete so it buries the
siding), and maybe just for laughs a drain tile on house side of patio,
going to daylight or a collector box. A good roof overhang or awning helps,
too. Patio itself needs footings, either traditional or a monolithic pour
based on shape of the hole and the fabric and rebar. Any good concrete
flatwork company will understand, and do what is appropriate for local
climate and soil conditions.

aem sends....

So it sounds like this might be a really bad thing to do. I live in
Austin, TX where we do occasionally have pretty serious (but brief)
freezes, but I don't know how much they affect the soil.

My yard is on a slight slope with the back (where the patio is going)
being higher than the front. I am planning on sloping the patio away
from the house with the end running into a dry creek bed that will
serve as drainage.

I guess I'll just have to see what the building inspector has to say
about it.

Thanks for all the help.

Dave

Hey, if you are here in Central Texas, you should pay
attention to this. I have only done 50 or so new slabs
against old slabs, but they have all been engineered. In
every instance, the engineer specified dowels into existing
concrete, spacing, etc. I always do this here as I have had
to remove 3 slabs (not mine) that have move away from the old
foundation enough that it caused problems.

I know that many of the people in here are against dowels and
some are against rebar at all. I have been working in this
area for about 30 years and I have never seen anything but 2nd
story patio slabs (lightweight concrete, 2" thick) poured
without rebar. And I have never seen a slab connection that
did not have dowels.

I have never had an engineer that is familiar with the soils
in this area spec anything but dowels and rebar for new
against existing. The soils in this area demand it.

--
Robert Allison
Rimshot, Inc.
Georgetown, TX

Well, I spoke to a contractor friend of mine here in town and he says
that in Austin you definitely *do* want to use rebar dowels to attach
the patio to the house. Frost heave is not a concern where I am
because even though it does freeze over for brief periods of time, the
soil itself never freezes.

He also said that since I have no experience working with concrete or
building frames that I would be crazy to try this on my own. I had
planned to build the frame myself and have the concrete delivered to
my house. Since I would be putting natural stone tile on top of the
concrete I wouldn't need to finish the surface, so I had planned on
having my buddies (who have some experience with concrete) help me
pour and screed it. However, given his prediction of total disaster
(his actual words) I'm thinking of doing a soft-set patio instead and
forgoing the concrete altogether. I was looking forward to a more
challenging job but I don't want to get myself into a big expensive
mess.

By the way, this is a 250 sq/ft patio we're talking about. At 4 inches
thick, it comes out to a little over 3 yards of concrete.

I did a search on this as we are getting ready to put in a huge patio in the back and the contractor said he would tie it into the house to keep it from moving. We're in MI with poor drainage - lots of clay ground here. What is the recommendation for that type of soil other than the obvious of proper ground prep?

--
For full context, visit https://www.homeownershub.com/mainte...se-228466-.htm

On Sun, 6 Sep 2020 16:00:04 +0000, Woofgang
wrote:

I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would
tie it into the house to keep it from moving.
We're in MI with poor drainage - lots of clay ground here.
What is the recommendation for that type of soil
other than the obvious of proper ground prep?


Are you talking about a large concrete pad ?
... or a wooden platform structure ?
Either way - ask your local building inspector a few
questions - he will need some info for the building permit anyway.
Our regulations require a building permit for a wooden deck -
- if it is tied to the house - even if it's a low height
not requiring a railing
Not tied to the house _might_ eliminate the need for a permit.
John T.

On 9/6/2020 12:00 PM, Woofgang wrote:
I did a search on this as we are getting ready to put in a huge patio in
the back and the contractor said he would tie it into the house to keep
it from moving.* We're in MI with poor drainage - lots of clay ground
here.* What is the recommendation for that type of soil other than the
obvious of proper ground prep?

We had a badly worn and cracked poured concrete patio in our backyard
right off a sliding glass door from a family room. The patio was flush
with the outer wall of the cinderblock foundation. There was
considerable deterioration of the near edge of the concrete due to
chronic moisture and slow settling of the concrete creating a
non-parallel surface against the foundation. Our masonry contractor
strongly advised us to have him leave an inch of space between the
foundation and near edge of the new one to minnimize the risk of similar
problems with the new pour. We took his advice. 8 years later the
entire patio slab, including the area immediately adjacent to the house
looked as good as the week the slab was poured.

On Sunday, September 6, 2020 at 12:00:11 PM UTC-4, Woofgang wrote:
I did a search on this as we are getting ready to put in a huge patio in the back and the contractor said he would tie it into the house to keep it from moving. We're in MI with poor drainage - lots of clay ground here. What is the recommendation for that type of soil other than the obvious of proper ground prep?

--
For full context, visit https://www.homeownershub.com/mainte...se-228466-.htm

1. Make sure your contractor pulls a permit and gets inspections.
2. Since it's attached to your house, the footings will probably need to extend below the frost line.
3. There's no way to keep it from moving.

Cindy Hamilton

Woofgang writes:

I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would tie it into the house to
keep it from moving. We're in MI with poor drainage - lots of clay
ground here. What is the recommendation for that type of soil other
than the obvious of proper ground prep?

Tying the patio to the house sounds like a very bad idea to me.
You must be thinking of using concrete, I wouldn't do that either.
Concrete moves around and cracks. You'll end up damaging your
foundation too.

Use pavers.

I put one in by myself about 20 years ago.
Still looks great. If I did have a problem
I could just lift up the damaged pavers and replace them.

The concrete patio I replaced was cracked and uneven.
Fortunately it wasn't tied into the house.
That would have just made things worse.


--
Dan Espen

I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would tie it into the house to
keep it from moving. We're in MI with poor drainage - lots of clay
ground here. What is the recommendation for that type of soil other
than the obvious of proper ground prep?

Tying the patio to the house sounds like a very bad idea to me.
You must be thinking of using concrete, I wouldn't do that either.
Concrete moves around and cracks. You'll end up damaging your
foundation too.
Use pavers.


I hope he's not thinking about anchoring a large concrete slab
to his house ? 1. Why ?
A properly-done concrete slab should last many many years -
- concrete is often used for driveways !
... much more stress and heavier traffic than a patio, yes ?
The modern patterns and colouring and pebble effects that
can be achieved with concrete can look great - just don't
choose the cheapest contractor !
My neighbour's driveway and patio are georgeous ! ... done
by his brother who is an experienced concrete tradesman.
John T.

On Sun, 6 Sep 2020 16:00:04 +0000, Woofgang
wrote:

I did a search on this as we are getting ready to put in a huge patio in the back and the contractor said he would tie it into the house to keep it from moving. We're in MI with poor drainage - lots of clay ground here. What is the recommendation for that type of soil other than the obvious of proper ground prep?

The secret of stable concrete is a stable base under it. I would
compact about 4" of gravel as a substrate then pour at least 4" of
concrete with steel in it. 6x6 #6 wire works but a lattice of #3 rebar
12-18" OC is better. When I did my driveway in Md, a road crew
wanting to make a few bucks on the side came by and put down #3 24" OC
plus the wire and my ex says it never cracked (1976 or so to date).

writes:


I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would tie it into the house to
keep it from moving. We're in MI with poor drainage - lots of clay
ground here. What is the recommendation for that type of soil other
than the obvious of proper ground prep?

Tying the patio to the house sounds like a very bad idea to me.
You must be thinking of using concrete, I wouldn't do that either.
Concrete moves around and cracks. You'll end up damaging your
foundation too.
Use pavers.


I hope he's not thinking about anchoring a large concrete slab
to his house ? 1. Why ?
A properly-done concrete slab should last many many years -
- concrete is often used for driveways !
.. much more stress and heavier traffic than a patio, yes ?
The modern patterns and colouring and pebble effects that
can be achieved with concrete can look great - just don't
choose the cheapest contractor !
My neighbour's driveway and patio are georgeous ! ... done
by his brother who is an experienced concrete tradesman.
John T.

I agree that concrete can look great and last a long time.

I think there is nothing that looks better than a paver
driveway. Even patterned and stained concrete.

I don't have any figures but I'm guessing pavers will outlast
concrete by a wide margin.

--
Dan Espen

On Sun, 06 Sep 2020 15:00:07 -0400, Dan Espen
wrote:

writes:


I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would tie it into the house to
keep it from moving. We're in MI with poor drainage - lots of clay
ground here. What is the recommendation for that type of soil other
than the obvious of proper ground prep?

Tying the patio to the house sounds like a very bad idea to me.
You must be thinking of using concrete, I wouldn't do that either.
Concrete moves around and cracks. You'll end up damaging your
foundation too.
Use pavers.


I hope he's not thinking about anchoring a large concrete slab
to his house ? 1. Why ?
A properly-done concrete slab should last many many years -
- concrete is often used for driveways !
.. much more stress and heavier traffic than a patio, yes ?
The modern patterns and colouring and pebble effects that
can be achieved with concrete can look great - just don't
choose the cheapest contractor !
My neighbour's driveway and patio are georgeous ! ... done
by his brother who is an experienced concrete tradesman.
John T.

I agree that concrete can look great and last a long time.
I think there is nothing that looks better than a paver
driveway. Even patterned and stained concrete.
I don't have any figures but I'm guessing pavers will outlast
concrete by a wide margin.


Do you mean "brick" pavestone ?
what we used to call interlocking brick
I do agree that it looks nice when first done -
but for the long haul - I'll take concrete -
- no weeds in the cracks requiring yearly round-up ;
- no refreshing the crack-sand every few years ..
John T.

writes:

On Sun, 06 Sep 2020 15:00:07 -0400, Dan Espen
wrote:

writes:


I did a search on this as we are getting ready to put in a huge patio
in the back and the contractor said he would tie it into the house to
keep it from moving. We're in MI with poor drainage - lots of clay
ground here. What is the recommendation for that type of soil other
than the obvious of proper ground prep?

Tying the patio to the house sounds like a very bad idea to me.
You must be thinking of using concrete, I wouldn't do that either.
Concrete moves around and cracks. You'll end up damaging your
foundation too.
Use pavers.


I hope he's not thinking about anchoring a large concrete slab
to his house ? 1. Why ?
A properly-done concrete slab should last many many years -
- concrete is often used for driveways !
.. much more stress and heavier traffic than a patio, yes ?
The modern patterns and colouring and pebble effects that
can be achieved with concrete can look great - just don't
choose the cheapest contractor !
My neighbour's driveway and patio are georgeous ! ... done
by his brother who is an experienced concrete tradesman.
John T.

I agree that concrete can look great and last a long time.
I think there is nothing that looks better than a paver
driveway. Even patterned and stained concrete.
I don't have any figures but I'm guessing pavers will outlast
concrete by a wide margin.

Do you mean "brick" pavestone ?

Yes.

what we used to call interlocking brick

On the patio I built I used those key shaped pavers.

I do agree that it looks nice when first done -
but for the long haul - I'll take concrete -
- no weeds in the cracks requiring yearly round-up ;
- no refreshing the crack-sand every few years ..

There is that.

This year I discovered I can make a really quick pass with the weed
whacker and wipe out the weeds in seconds.
I'm not so meticulous that I feel the need to mess with the sand.

I find the repeating pattern really appealing to the eyes.
My driveway is asphalt now but I keep toying with the idea
of pavers.

I did my own patio, but the driveway is a bit more than I want to
undertake.


--
Dan Espen

I do agree that it looks nice when first done -
but for the long haul - I'll take concrete -
- no weeds in the cracks requiring yearly round-up ;
- no refreshing the crack-sand every few years ..

There is that.

This year I discovered I can make a really quick pass with the weed
whacker and wipe out the weeds in seconds.
I'm not so meticulous that I feel the need to mess with the sand.
I find the repeating pattern really appealing to the eyes.
My driveway is asphalt now but I keep toying with the idea
of pavers.
I did my own patio, but the driveway is a bit more than I want to
undertake.


For the last few years, I've been using double-strength vinegar
on my gravel driveway weeds - applied with a hand-pump
garden sprayer - it works fairly well - ~ 3 or 4 applications
per year - ie : not as lethal as round-up -
... but it adds up to ~ $ 15. worth of vinegar and no PPE.
ps: I'm a paid-up member of the Green Party
so I gotta make it look like I really care .. :-)
It's gotta be the 10 % cleaning vinegar - accept no substitutes.
I've used it on the walkway pave-stone weeds but worried
about the possible staining and/or acid effect on the bricks
over too-many years of use .. ?
Weed-whacking the crack weeds is ~ 5 times per year
for me ... and takes 5 times as long as doiing it on the
old ugly pre-cast sidewalk slabs ...
more cracks = way more weeds !
John T.

writes:


I do agree that it looks nice when first done -
but for the long haul - I'll take concrete -
- no weeds in the cracks requiring yearly round-up ;
- no refreshing the crack-sand every few years ..

There is that.

This year I discovered I can make a really quick pass with the weed
whacker and wipe out the weeds in seconds.
I'm not so meticulous that I feel the need to mess with the sand.
I find the repeating pattern really appealing to the eyes.
My driveway is asphalt now but I keep toying with the idea
of pavers.
I did my own patio, but the driveway is a bit more than I want to
undertake.

For the last few years, I've been using double-strength vinegar
on my gravel driveway weeds - applied with a hand-pump
garden sprayer - it works fairly well - ~ 3 or 4 applications
per year - ie : not as lethal as round-up -
.. but it adds up to ~ $ 15. worth of vinegar and no PPE.
ps: I'm a paid-up member of the Green Party
so I gotta make it look like I really care .. :-)
It's gotta be the 10 % cleaning vinegar - accept no substitutes.
I've used it on the walkway pave-stone weeds but worried
about the possible staining and/or acid effect on the bricks
over too-many years of use .. ?
Weed-whacking the crack weeds is ~ 5 times per year
for me ... and takes 5 times as long as doiing it on the
old ugly pre-cast sidewalk slabs ...
more cracks = way more weeds !
John T.

I like to preserve the environment but the environment has no business
on my patio. Let green things grow around it but not on it.

I'm already out there with my battery weed whacker edging the lawn.
My patio is about 20x20. It really only takes 60 seconds or so
the get the weeds. What I really like is it picks up the moss
and sends it flying. Roundup didn't do much to the moss at all.

As for vinegar I think you may be right an acid isn't going to be so
good for bricks. Then there is this:

http://www.theecomum.com/blog/eco-my...r-cleaner-nope

Like a lot of things, making things causes problems too.

If we studied this stuff to death, who knows how Roundup would stack up
against vinegar. My attitude is don't use more than you need to and
don't worry about the small stuff. I want my patio to be inhospitable
to plant life anyway.

Anyway just mowed the back an hour ago, good time to go out there
and edge it. Later.

--
Dan Espen