Replies

1. 
   Piffin | May 18, 2009 12:37pm | #1

   Are you sure there is no real subfloor under the Pboard? It is hard to believe you can even walk on 1/2" all this time.

   normal was to use 5/8 or 3/4" ply or advantec subfloor, then 1/2" particle board underlayment for carpet or vinyl.

   Particle board does not have the integrity required to hold flooring nails for your new flooring, so if that is all you have, it needs to be replaced.

    

    

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1. 
   bd | May 18, 2009 12:55pm | #2

   I don't know about 1/2" PB, but there were plenty of houses built around here w/ 3/4" particle board subfloor, esp under those areas getting vinyl or carpet. My neighbor's house is that way even though I warned him about it after I saw it going in. In addition, the PB sheets in his house were only nailed around the perimeter, not in the field at all. All the furniture shook when you walked across the room.

1. 
   Piffin | May 18, 2009 01:11pm | #3

   Lady called once because of a washing machine that was shaking and not level.Turned out that the rear legs had worn a hole right thru 5/8" PBd and that was the only subfloor. I got to looking around and saw that the whole house had nothing but PBd for subfloor and was sagging about 3/8" every span between joists except where partition walls ran parallel and there it sagged as much as 3/4"Had been built as one of five on that street by a lawyer, cum speculator, cum builder, cum house inspector, LOL 

    

   Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!

1. 
   bd | May 18, 2009 01:51pm | #5

   The sad part, about the neighboring house that I described, is that my friend went to a lot of trouble to locate & hire one of the "best" contractors in the county at that time.It's really hard to find "Breaktime quality" contractors in the real world. You fellows are a rarer breed than you realize.

1. 
   Butch70 | May 18, 2009 02:15pm | #6

   My error in typing last night guys ----, the existing subfloor is 3/4 in. thick!  I also am leaning toward replacing the subfloor under the areas where i will have the 3/4 in wood flooring installed. 

   Since the floor joist and the wood flooring will be running in the same direction do you think that the flooring in between the floor joist will have sufficient support and nailing????

2. 
   Piffin | May 18, 2009 02:57pm | #9

   The flooring and joists running same direction makes no diff IF the subfloor is a proper subfloor.But now that you corrected the thickness, I still don't know if it is all particle board or real subfloor. If pbd, it must be replaced to nail down wood flooring because the nails won't hold in Pbd for long. 

    

   Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!

3. 
   Butch70 | May 18, 2009 03:37pm | #12

   Thanks!

4. 
   alwaysoverbudget | May 18, 2009 03:03pm | #10

   when looking at this from the bottom does the surfce look like chips of wood pressed together?thats called osb

    or does it look more like sawdust that has been glued together?thats particle board

   take a look and drill to see thickness and let us know.

    

   i can't imagine particle board during construction,must not rain there much.YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'TMOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THEDUCT TAPE.

5. 
   Dinosaur | May 18, 2009 08:56pm | #15

   Since the floor joist and the wood flooring will be running in the same direction do you think that the flooring in between the floor joist will have sufficient support and nailing????

   If you pull the p-board and replace it with ¾" plywood, yes.

    

   Another option you may wish to consider is to put down 2x4 or 2x6 roof-decking directly over the joists with no subfloor. It measures about 1-3/8" thick so your finished floor height would be essentially the same as ¾" ply + ¾" finish floor. And you don't have to pay for the plywood or the labour to install it.

   That would have to be laid perpendicular to the joists, however; I wouldn't want to count on nailed-in blocking to hold up a plank floor with no sheet goods under it to spread out the loads.

   Dinosaur

   How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....

6. 
   Butch70 | May 21, 2009 04:57am | #16

   Just an update!  I currently have 3/4 inch osb (not particle board)  for a subfloor and after reading all of your advice, I have decided to take up the osb subfloor in the area where I will install the 3/4 in wood flooring and screw and glue 3/4 in plywood as a subfloor to nail the the wood flooring to. 

   Thanks for all the input!!!!!!!!!!!!

7. 
   alwaysoverbudget | May 21, 2009 05:46am | #17

   this could be more fun than you think. go back under the house and look along the joist and look for a little glue squeeze out. see any?

   if i had 3/4 osb that was either screwed or glued ,i'd stick with that and roll on.

   advantech is a osb product......................YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'TMOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THEDUCT TAPE.

8. 
   Hudson Valley Carpenter | May 21, 2009 07:12pm | #18

    I currently have 3/4 inch osb (not particle board)  for a subfloor...

   Then you're in luck.   No need to remove and replace that with anything. 

   3/4" OSB if fine as a subfloor for a new hardwood floor.

9. 
   Butch70 | May 21, 2009 07:22pm | #19

   Thanks for your input!

10. 
    Sbds | May 21, 2009 09:59pm | #20

    I just did redid two rooms in my house. I had flood damage. I ripped out the old 3/4 inch strip wood floor and the old plywood. I then put down 3/4 inch OSB and a new 3/4 inch oak strip floor. No problem. If you have 3/4 OSB that will work fine.

2. 
   Hudson Valley Carpenter | May 18, 2009 01:37pm | #4

   I'd replace the subfloor.  Blocking, combined with particle board, isn't nearly as good a solution. 

   I'm surprised to hear that anyone has used particle board as a subfloor.  That might  be an indication of other substandard materials and techniques which could cause problems in the future.

3. 
   Frankie | May 18, 2009 02:20pm | #7

   Is there a basement or crawl space under the dining room which is accessible to confirm the pb is the only sheathing installed?

   A single 1" bore through the PB can also confirm if there is another layer of something below.

   You need 3/4 plywood/ underlayment as a subfloor below the finish floor in order for the nails or staples to grab/ hold.

   Do not install bridging at 16"oc and nail the finished floor to them. A) it's a lot of additional work and B) the finish floor will then act as a structural floor (part of the diaphragm of the floor).

   Frankie

   Flay your Suffolk bought-this-morning sole with organic hand-cracked pepper and blasted salt.

   Thrill each side for four minutes at torchmark haut. Interrogate a lemon.

   Embarrass any tough roots from the samphire. Then bamboozle till it's al dente with that certain je ne sais quoi.

   Arabella Weir as Minty Marchmont - Posh Nosh

1. 
   Butch70 | May 18, 2009 02:28pm | #8

   Thanks!

    

   I will confirm the thickness and the material as  you have described.

2. 
   DanH | May 18, 2009 03:08pm | #11

   > A single 1" bore through the PB can also confirm if there is another layer of something below.Actually, a 1/4" hole and a piece of wire can confirm the thickness. Bend a 1/8" L on the end of the wire, stick it in and catch it on the edge, then withdraw with your thumb marking the depth.
   The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

1. 
   Frankie | May 18, 2009 08:39pm | #13

   1/4" bore will tell me thickness.1" bore will tell me thickness and of what material(s). More conclusive information.F

   Flay your Suffolk bought-this-morning sole with organic hand-cracked pepper and blasted salt.

   Thrill each side for four minutes at torchmark haut. Interrogate a lemon.

   Embarrass any tough roots from the samphire. Then bamboozle till it's al dente with that certain je ne sais quoi.

   Arabella Weir as Minty Marchmont - Posh Nosh

1. 
   DanH | May 18, 2009 08:42pm | #14

   True. Especially if you use a 1" hole saw so you can examine the extracted plugs.
   As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz