plywood subfloor question
 

the carpet guy was replacing some carpet.
it's laid down on a plywood subfloor.
i noticed one gap in the laid down panels
that you could peek into the basement thru.

you could also get a ruler thru the gap &
measure the plywood thickness.

i was shocked to realize it wasn't that
thick.

the panels are stamped 23/32, and tongue
and groove - google'ing it - it seems the
23/32" is the same as 3/4 - but these panels
are NOT even close to being 3/4" thick ...

now i must be missing something here in the
way thickness is depicted.

should the panel really be 3/4" thick (ie.
measured on a ruler), or is there some "trade"
custom in measurements of plywood subfloor
thickness that is used ? i would imagine an
actual 3/4" thick plywood panel would be a very
heavy dead load on the joist.

it actually measured on the ruler a little less
than 1/4" thick - and the blueprints call for a
standard 40 psf load limit.

plywood subfloor question
 

the panels should indeed be 3/4" (well, actually 23/32) measured on a
ruler. Are you sure you are measuring the full sheet, and not bumping
the tongue with your ruler or something? if it was actually 1/4"
thick, you would definitly notice the flimsyness and there would be
bellies between the joists.

plywood subfloor question
 

You may be confusing the structural deck and the underlayment.
TB

plywood subfloor question
 

If it was 24/32 then it would be exactly the same as 3/4. So 23/32 is
just 1/32 thinner than 3/4 and a big difference from 1/4.

plywood subfloor question
 

"marson" wrote in message
oups.com...
the panels should indeed be 3/4" (well, actually 23/32) measured on a
ruler. Are you sure you are measuring the full sheet, and not bumping
the tongue with your ruler or something? if it was actually 1/4"
thick, you would definitly notice the flimsyness and there would be
bellies between the joists.



well, there was a small gap in between 2 panels, and i
could stick a ruler into the gap (and could peek thru it
to see the basement). so when i stuck the ruler into the
gap, and measured the plywood thickness at that gap edge,
it was about 1/4" or so.

but yet the plywood panel underneath is stamped 23/32,
tongue & groove.

the panels are all flat and don't seem to be flimsy, so
it's a mystery that made me ask if i'm measuring it wrong.

so if it really was 1/4" thick, i'd know it for sure ??

the joists are 2x10's 16" o.c. (and some areas are double
and triple joisted, and there are wood cross braces in
between most of them - there's a fireplace in the same
room) with those plywood subfloor panels.

plywood subfloor question
 

You should measure the plywood by putting your ruler down into the gap so
that it touches the top of the joist, then measure the thickness to the
surface. I am sure it will measure close to 3/4".

wrote in message
oups.com...
If it was 24/32 then it would be exactly the same as 3/4. So 23/32 is
just 1/32 thinner than 3/4 and a big difference from 1/4.

plywood subfloor question
 

Some subfloor is 5/8" thick panels. I would be more concerned with be able
to peak into the basement. Sounds like somebody went off layout. I would
nail a 2X4 alongside the joist then nail the panel down.



"duckdude" wrote in message
...


the carpet guy was replacing some carpet.
it's laid down on a plywood subfloor.
i noticed one gap in the laid down panels
that you could peek into the basement thru.

you could also get a ruler thru the gap &
measure the plywood thickness.

i was shocked to realize it wasn't that
thick.

the panels are stamped 23/32, and tongue
and groove - google'ing it - it seems the
23/32" is the same as 3/4 - but these panels
are NOT even close to being 3/4" thick ...

now i must be missing something here in the
way thickness is depicted.

should the panel really be 3/4" thick (ie.
measured on a ruler), or is there some "trade"
custom in measurements of plywood subfloor
thickness that is used ? i would imagine an
actual 3/4" thick plywood panel would be a very
heavy dead load on the joist.

it actually measured on the ruler a little less
than 1/4" thick - and the blueprints call for a
standard 40 psf load limit.

plywood subfloor question
 

"duckdude" wrote:


"marson" wrote in message
roups.com...
the panels should indeed be 3/4" (well, actually 23/32) measured on a
ruler. Are you sure you are measuring the full sheet, and not bumping
the tongue with your ruler or something? if it was actually 1/4"
thick, you would definitly notice the flimsyness and there would be
bellies between the joists.



well, there was a small gap in between 2 panels, and i
could stick a ruler into the gap (and could peek thru it
to see the basement). so when i stuck the ruler into the
gap, and measured the plywood thickness at that gap edge,
it was about 1/4" or so.

but yet the plywood panel underneath is stamped 23/32,
tongue & groove.

Tongue & groove means the edge of the plywood, at the mill, has a 1/4"
cut in the top and bottom sides, leaving the middle 1/4" to stick into
the slot cut in the other edge of the next sheet of plywood.

So if you have a slight gap between the sheet, but not enough to expose
the whole edge, you could measure just the top cut on the T&G.

It makes for a stronger joint to have the two pieces interlock.
--
NewsGuy.Com 30Gb $9.95 Carry Forward and On Demand Bandwidth

plywood subfloor question
 

you could try removing a floor register and measuring there.

"duckdude" wrote in message
...

"marson" wrote in message
oups.com...
the panels should indeed be 3/4" (well, actually 23/32) measured on a
ruler. Are you sure you are measuring the full sheet, and not bumping
the tongue with your ruler or something? if it was actually 1/4"
thick, you would definitly notice the flimsyness and there would be
bellies between the joists.



well, there was a small gap in between 2 panels, and i
could stick a ruler into the gap (and could peek thru it
to see the basement). so when i stuck the ruler into the
gap, and measured the plywood thickness at that gap edge,
it was about 1/4" or so.

but yet the plywood panel underneath is stamped 23/32,
tongue & groove.

the panels are all flat and don't seem to be flimsy, so
it's a mystery that made me ask if i'm measuring it wrong.

so if it really was 1/4" thick, i'd know it for sure ??

the joists are 2x10's 16" o.c. (and some areas are double
and triple joisted, and there are wood cross braces in
between most of them - there's a fireplace in the same
room) with those plywood subfloor panels.

plywood subfloor question
 

According to John Hines :

Tongue & groove means the edge of the plywood, at the mill, has a 1/4"
cut in the top and bottom sides, leaving the middle 1/4" to stick into
the slot cut in the other edge of the next sheet of plywood.

[Or the reverse ;-)]

So if you have a slight gap between the sheet, but not enough to expose
the whole edge, you could measure just the top cut on the T&G.

It makes for a stronger joint to have the two pieces interlock.

Indeed.

It's also possible he's seeing a ripped off edge that doesn't quite meet,
and has been undercut by a chunk split out of the underside of the ply.

In any event, 1/4" floor sheathing would be more than flimsy. If you
stomped on it, there's a good chance of going through. You'd get a very
queasy feeling walking on it.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.