I recently bought a 1968 bungalow that needs some renovations and
updating. One of the bathrooms has a crack in the concrete floor where
the tub meets the wall. I chisled out the 3" thick piece of concrete
that was cracked and noticed that there is severe water damage to a
joist that sits below the slab. I believe the previous owners kept
using the shower (only one in the house, so it got plenty of use) and
let water seap down in the crack.

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath? I have
noticed a lot people just banging on it with a hammer, but I am scared
I might be adding weight to the weak joists below. Cutting the concrete
is also an option I guess, but do you just set the saw to not cut more
than 3" (slab thickness)?

Any suggestions would be helpful. I jumped head first into this
project. This is my first house and it was a foreclosure, so I have
lots of work ahead of me.

.......Thanks in advance for the responses.

wrote:
snip
So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath?

In short: unless you really _really_ have to, you don't. Inspect
underneath for plumbing and elctirical lines and turn them off or reloacte
them as you are able and then poynd away. If somthing underneath is
rotten and breaks, well, it was going to need replacing anyway, so you've
just started on that demo a bit earlier than you were otherwise going to.

Now obviously, if the beams involved are doing major load carrying and are
in danger of causing some sort imminent collapse, then you don't want to
just start banging about, but then you really oughtn'y be doing _any_ work
in the area untill you get things shored up or otherwisee braced.

But for some possibly rotten wood under a bathroom? Just hammer away.




John
--
Remove the dead poet to e-mail, tho CC'd posts are unwelcome.
Mean People Suck - It takes two deviations to get cool.
Ask me about joining the NRA.

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath?

I don't get it at all. Normally, "what's underneath" a concrete slab in
a home is just dirt and gravel. Is there a basement underneath this
concrete floor? If so, you would just go down and look at the joists
from below, so I'm assuming there is NOT a basement or crawl space.

The wood you are finding down there could be bits of the wood they used
to make the frame into which the concrete was poured. It serves no
purpose now at all, and is fine just rotting away under there, since it
is buried in dirt anyway.

Now, cracks in concrete are inevitable and unavoidable. How bad was the
crack? Just a hairline, or could you slip a pencil down it/ Or more?

Certainly make sure your tub is not leaking, but before you go ripping
out your slab, maybe you can fix this problem by (a) ignoring it
because it isn't really a problem, or (b), just patching the one spot
from above, sealing the area, and making sure the tub isn't leaking
anywhere.

-Kevin

kevin wrote:
So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath?

I don't get it at all. Normally, "what's underneath" a concrete slab in
a home is just dirt and gravel. Is there a basement underneath this
concrete floor? If so, you would just go down and look at the joists
from below, so I'm assuming there is NOT a basement or crawl space.

The wood you are finding down there could be bits of the wood they used
to make the frame into which the concrete was poured. It serves no
purpose now at all, and is fine just rotting away under there, since it
is buried in dirt anyway.

Now, cracks in concrete are inevitable and unavoidable. How bad was the
crack? Just a hairline, or could you slip a pencil down it/ Or more?

Certainly make sure your tub is not leaking, but before you go ripping
out your slab, maybe you can fix this problem by (a) ignoring it
because it isn't really a problem, or (b), just patching the one spot
from above, sealing the area, and making sure the tub isn't leaking
anywhere.

-Kevin

Good suggestions. I guess I can provide some more info that I forgot. I
do have a crawl space and I can't see concrete from the crawlspace, so
it was poured in the house and not just inserted as a whole there.

The "crack" basically separated a corner (which I removed to find the
rotten board underneath). The joists look ok from the bottom, but that
one area that wasn't properly sealed definitely needs replacing. I
figured since the slab is missing a corner and the area needs
repairing, I could be pro-active and remove the slab.

Thanks for the suggestions....I can already tell this is going to be a
fun task.

wrote:
I recently bought a 1968 bungalow that needs some renovations and
updating. One of the bathrooms has a crack in the concrete floor where
the tub meets the wall. I chisled out the 3" thick piece of concrete
that was cracked and noticed that there is severe water damage to a
joist that sits below the slab. I believe the previous owners kept
using the shower (only one in the house, so it got plenty of use) and
let water seap down in the crack.

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath? I have
noticed a lot people just banging on it with a hammer, but I am scared
I might be adding weight to the weak joists below. Cutting the concrete
is also an option I guess, but do you just set the saw to not cut more
than 3" (slab thickness)?

Any suggestions would be helpful. I jumped head first into this
project. This is my first house and it was a foreclosure, so I have
lots of work ahead of me.

......Thanks in advance for the responses.

A very puzzling scenario! You have the tub pulled out and found a
concrete slab beneath it and on top of wood rafters? Tub drains go
through the slab? Whole bathroom has concrete slab floor? Any chance
it is just an old concrete shower pan that someone put flooring over and
put a tub on top? What is there in the crawlspace that comes THROUGH
the slab? An old shower pan would be a very likely place for leaks and
rot, but I would hack away at a floor not knowing where I'm going.

johnnymo wrote:

kevin wrote:

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath?

I don't get it at all. Normally, "what's underneath" a concrete slab in
a home is just dirt and gravel. Is there a basement underneath this
concrete floor? If so, you would just go down and look at the joists
from below, so I'm assuming there is NOT a basement or crawl space.

The wood you are finding down there could be bits of the wood they used
to make the frame into which the concrete was poured. It serves no
purpose now at all, and is fine just rotting away under there, since it
is buried in dirt anyway.

Now, cracks in concrete are inevitable and unavoidable. How bad was the
crack? Just a hairline, or could you slip a pencil down it/ Or more?

Certainly make sure your tub is not leaking, but before you go ripping
out your slab, maybe you can fix this problem by (a) ignoring it
because it isn't really a problem, or (b), just patching the one spot
from above, sealing the area, and making sure the tub isn't leaking
anywhere.

-Kevin


Good suggestions. I guess I can provide some more info that I forgot. I
do have a crawl space and I can't see concrete from the crawlspace, so
it was poured in the house and not just inserted as a whole there.

The "crack" basically separated a corner (which I removed to find the
rotten board underneath). The joists look ok from the bottom, but that
one area that wasn't properly sealed definitely needs replacing. I
figured since the slab is missing a corner and the area needs
repairing, I could be pro-active and remove the slab.

Thanks for the suggestions....I can already tell this is going to be a
fun task.


Sounds to me like you have a cement subfloor.
Wooden "slats" are laid between the joists to create a base for
the concrete mix, which may only be 2 to 4" deep. The mix may have
steel mesh in it for strength. The whole system forms a very
rigid base for ceramic tile while not overloading the joists.

Jim

You can inspect joists and structure from the crawl space below and you
say it looks OK. So, why demo it? If there is only a small area of
rot damage and it can be repaired, I'd focus on doing that, not
creating a bigger project.

Norminn wrote:
wrote:
snip
......Thanks in advance for the responses.

A very puzzling scenario! You have the tub pulled out and found a
concrete slab beneath it and on top of wood rafters? Tub drains go
through the slab? Whole bathroom has concrete slab floor? Any chance
it is just an old concrete shower pan that someone put flooring over and
put a tub on top? What is there in the crawlspace that comes THROUGH
the slab? An old shower pan would be a very likely place for leaks and
rot, but I would hack away at a floor not knowing where I'm going.

He's saying "slab" but what I think he's looking at is a floor that was
done as a mud job, (where instead of concrete backer board, and layer of
tar paper expanded steel and a dry mix of concrete is put over the
subfloor).

Still, leaving that "slab" intact and just work on the damaged area is a
good point.


John
--
Remove the dead poet to e-mail, tho CC'd posts are unwelcome.
Mean People Suck - It takes two deviations to get cool.
Ask me about joining the NRA.

wrote:
Norminn wrote:
wrote:
snip
......Thanks in advance for the responses.

A very puzzling scenario! You have the tub pulled out and found a
concrete slab beneath it and on top of wood rafters? Tub drains go
through the slab? Whole bathroom has concrete slab floor? Any chance
it is just an old concrete shower pan that someone put flooring over and
put a tub on top? What is there in the crawlspace that comes THROUGH
the slab? An old shower pan would be a very likely place for leaks and
rot, but I would hack away at a floor not knowing where I'm going.

He's saying "slab" but what I think he's looking at is a floor that was
done as a mud job, (where instead of concrete backer board, and layer of
tar paper expanded steel and a dry mix of concrete is put over the
subfloor).

Still, leaving that "slab" intact and just work on the damaged area is a
good point.


John
--
Remove the dead poet to e-mail, tho CC'd posts are unwelcome.
Mean People Suck - It takes two deviations to get cool.
Ask me about joining the NRA.

Yea, so because I pulled that corner piece out which was cracked and
had separated from the "slab" I can tell that the concrete measure 3"
from wood to the top of the concrete. The top of the concrete is flush
with the rest of the house's subfloor. It is flush with the kitchen's
subfloor and the hallway to the bedrooms. The cast iron tub is sitting
on regular diagonal wood subflooring which is also flush with the top
of the concrete.

Can the concrete be poured between the joists and over the top of the
joists by a half inch making it flush with the rest of the house. If
so that would suck trying break that concrete out of there.

I obviously need to look at it more from the underside tonight to
figure out if this is going to be worth it or not. Let me take a look
tonight. The other bathroom (1/2 bath) only has a two inch slab and is
in good shape.

On 16 Aug 2006 06:50:14 -0700, wrote:


I recently bought a 1968 bungalow that needs some renovations and
updating. One of the bathrooms has a crack in the concrete floor where
the tub meets the wall. I chisled out the 3" thick piece of concrete
that was cracked and noticed that there is severe water damage to a
joist that sits below the slab. I believe the previous owners kept
using the shower (only one in the house, so it got plenty of use) and
let water seap down in the crack.

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath? I have
noticed a lot people just banging on it with a hammer, but I am scared
I might be adding weight to the weak joists below. Cutting the concrete
is also an option I guess, but do you just set the saw to not cut more
than 3" (slab thickness)?

Any suggestions would be helpful. I jumped head first into this
project. This is my first house and it was a foreclosure, so I have
lots of work ahead of me.

......Thanks in advance for the responses.

Leave it alone and only patch what needs patching.

You have already gotten some really bad advice so I thought I would
chime in.

"and noticed that there is severe water damage to a joist that sits
below the slab"

Any time you have water damage to wood you must be able to see the
total wood area to asses the exstent of the damage there is no other
way of doing it. This is a very odd situation but I have seen this
concrete between joists before. Unfortunally it is a method that is
full of problems. If you are going to do this house right take this
whole thing out in this bath and the other one, examine the joists,
repair as needed and put in a real sub floor. Chances are based on the
age of the house and the fact that you have a crawl space the floor
joists are probably sitting on pier blocks. If there was continued
water under the house you could have pier blocks that have shifted or
soil that has eroded out near a block or some other damage from the
water under the house. This all needs to be checked out before you just
put a "band-aid" on this floor because if there is something down there
it will come back to haunt you....
Yes you can do it another way but this is the right way.....

I have
noticed a lot people just banging on it with a hammer, but I am scared
I might be adding weight to the weak joists below.

Cutting the concrete is also an option I guess, but do you just set the saw to not cut more
than 3" (slab thickness)?
Chances are you do not have a gas saw and will just be using a circular
saw in which case you will only be able to get about 2 1/2 inches down
with so I would not worry about that. I would make several cuts in the
concrete first dividing the areat up into about 18" sections. then use
a "sledge hammer" to break the concrete. Start in a corner or the edge
of the part of the floor that is already missing and work
backwards....Concrete breaks very easily if it has some where to go.
First hit the crack in the immediate area to the piece that is missing
then on the very edge of the part that is already broken off. Repeate
this sequence till you have removed it all. remember allways hit the
concrete on the cuts closes to the piece you just broke off and then
about 2 or 3" in from the edge. If you start in the center of the floor
or in the center of a slab of concrete it will take yo forever because
the concrete needs space to break. When taking out concrete always
start on an edge NEVER in the middle



wrote:
I recently bought a 1968 bungalow that needs some renovations and
updating. One of the bathrooms has a crack in the concrete floor where
the tub meets the wall. I chisled out the 3" thick piece of concrete
that was cracked and noticed that there is severe water damage to a
joist that sits below the slab. I believe the previous owners kept
using the shower (only one in the house, so it got plenty of use) and
let water seap down in the crack.

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath? I have
noticed a lot people just banging on it with a hammer, but I am scared
I might be adding weight to the weak joists below. Cutting the concrete
is also an option I guess, but do you just set the saw to not cut more
than 3" (slab thickness)?

Any suggestions would be helpful. I jumped head first into this
project. This is my first house and it was a foreclosure, so I have
lots of work ahead of me.

......Thanks in advance for the responses.

Well....I examined the underside of the bathroom a little closer last
night. It appears that about 3 subfloor boards are not looking very
pretty. I will feel more comfortable pulling out the concrete to get a
good assessment and fix what needs to be fixed.

I guess I will try the sawing method. It sounds a little dusty, but I
guess it is the easy way and then bang out the cut pieces. I guess
there is recommended blade for cutting tile/concrete?

Thanks for the suggestions. It is going to be fun. Wish me luck.

Use a good quality Diamond blade splurge on this blade believe me it is
worth it. To keep the dust down have a helper spray (with a garden hose
or pump sprayer) a small stream of water onto the blade while
cutting...not too much just enough to keep the dust wet you will catch
on quickly how to adjust the stream of water..

Yes you can use a carbide blade to cut concrete and yes they are MUCH
cheaper than the diamond blade but you get what you pay for......
good luck just go a little at a time and im sure you will be fine.

johnnymo wrote:
Well....I examined the underside of the bathroom a little closer last
night. It appears that about 3 subfloor boards are not looking very
pretty. I will feel more comfortable pulling out the concrete to get a
good assessment and fix what needs to be fixed.

I guess I will try the sawing method. It sounds a little dusty, but I
guess it is the easy way and then bang out the cut pieces. I guess
there is recommended blade for cutting tile/concrete?

Thanks for the suggestions. It is going to be fun. Wish me luck.

Thanks for the suggestions. It is going to be fun. Wish me luck.

I have never seen or even heard of such a crazy way to do a subfloor.
But still I wonder if you aren't making this too hard. Lets assume you
want to remove the concrete. You seem to indicate that it is sunk about
2 1/2 inches down into the joist bays, and then comes up about 1/2 inch
over the top of the joists. It must be resting on something since you
can't see the concrete from the crawl space. I'm going to guess that
there is some wood slats of some sort below the concrete, since that
1/2 inch lip would not hold the concrete so great.

Can you go into the crawl space and just cut out the rotten and
remaining slats. Being careful of course to not let the concrete fall
on you while doing this. After, you have just a 1/2 of concrete on top
of each joist. Bust that up, or cut it, and the whole bay would fall
down into the crawlspace.

But I am probably missing something given the convoluted history of
this thread. Good luck anyway. And get some pics will ya already.

It may be much thinner. My mud base is probably an inch thick.


"Speedy Jim" wrote in message
t...
johnnymo wrote:

kevin wrote:

So....I would like to pull up the concrete slab to find out what I am
up against. My question is, what is the easiest way to get this
concrete up causing the least damage to what's underneath?

I don't get it at all. Normally, "what's underneath" a concrete slab in
a home is just dirt and gravel. Is there a basement underneath this
concrete floor? If so, you would just go down and look at the joists
from below, so I'm assuming there is NOT a basement or crawl space.

The wood you are finding down there could be bits of the wood they used
to make the frame into which the concrete was poured. It serves no
purpose now at all, and is fine just rotting away under there, since it
is buried in dirt anyway.

Now, cracks in concrete are inevitable and unavoidable. How bad was the
crack? Just a hairline, or could you slip a pencil down it/ Or more?

Certainly make sure your tub is not leaking, but before you go ripping
out your slab, maybe you can fix this problem by (a) ignoring it
because it isn't really a problem, or (b), just patching the one spot
from above, sealing the area, and making sure the tub isn't leaking
anywhere.

-Kevin


Good suggestions. I guess I can provide some more info that I forgot. I
do have a crawl space and I can't see concrete from the crawlspace, so
it was poured in the house and not just inserted as a whole there.

The "crack" basically separated a corner (which I removed to find the
rotten board underneath). The joists look ok from the bottom, but that
one area that wasn't properly sealed definitely needs replacing. I
figured since the slab is missing a corner and the area needs
repairing, I could be pro-active and remove the slab.

Thanks for the suggestions....I can already tell this is going to be a
fun task.


Sounds to me like you have a cement subfloor.
Wooden "slats" are laid between the joists to create a base for
the concrete mix, which may only be 2 to 4" deep. The mix may have
steel mesh in it for strength. The whole system forms a very
rigid base for ceramic tile while not overloading the joists.

Jim

Done....thanks for everyone's suggestions. I took a sledge hammer to
it. Since I had the missing corner piece, the concrete started to
separate nicely soley focussing on that area first. I did kind of
starting hitting at the slab from straight above, which ended up going
straight through the rotten subfloor below, so I modified my method and
started swinging more at an angle toward the areas that I had already
removed and it worked much better. Probably took me an 1 hour and half
to remove a 5'x7'x3" slab. Joist look good, subfloor has got to go
around the tub.

Thanks again for the suggestions.

johnnymo wrote:

Done....thanks for everyone's suggestions. I took a sledge hammer to
it. Since I had the missing corner piece, the concrete started to
separate nicely soley focussing on that area first. I did kind of
starting hitting at the slab from straight above, which ended up going
straight through the rotten subfloor below, so I modified my method and
started swinging more at an angle toward the areas that I had already
removed and it worked much better. Probably took me an 1 hour and half
to remove a 5'x7'x3" slab. Joist look good, subfloor has got to go
around the tub.

Told ya.

Thanks again for the suggestions.

You're welcome and thanks for letting us know how it came out.



John
--
Remove the dead poet to e-mail, tho CC'd posts are unwelcome.
Mean People Suck - It takes two deviations to get cool.
Ask me about joining the NRA.