Subfloor options: OSB vs Particle board
A common question prior to new floor installation is which type of subfloor to use. People often confuse OSB with particle board. In one sentence – particle board is often used as a subfloor for carpets, OSB is used as a primary subfloor for any flooring, including hardwood. Now let’s take a closer look at both of them.
OSB (Oriented Strand Board)
OSB or oriented strand board is commonly used as a base subfloor because of its stability and affordable price. Oriented strand board is made of chunks of wood, big wood strands and pieces pressed and glued together. Big chunks give each board unique character so every board is quite unique and full of colors. Boards are 8′ by 4′ in size and comes in different thickness, varying from 1/2″ to 1-1/4″. National Wood Flooring Association approves usage of OSB as a subfloor for hardwood flooring with nail-down installation with minimum thickness of 23/32″ and recommended thickness of 7/8″ or 1-1/8″. Proper acclimatization must be done prior to subfloor installation to achieve stable, long-lasting results. In addition to that, underlay paper must be installed between hardwood and OSB. Nowadays, most hardwood manufacturers approve OSB board usage as a proper subfloor for wood flooring.
On the other hand, OSB boards are not suited for tile installation. Both ceramic and porcelain tile require hardyback or cement board be installed over existing subfloor prior to tile installation. (Note: New Floors Inc does not sell or install Tile)
Particle Board
Particle board (or Fiberboard) has a different structure – it’s made of small wood chips, particles and wood dust. This interwoven compound is pressed and glued together, but it’s brittle, doesn’t hold nails well and can be easily broken with bare hands. In general, particle boards are used as an addition to regular subfloor for wall- to-wall carpet installation. Particle board comes in different densities, but still softer compared to OSB boards. The most popular types are HDF and MDF – High/Medium Density Fiberboard, with fewer chips and more dust. Particle board and fiber board are more uniform in appearance, and some are painted by the manufacturer for moisture resistance. However, these are NOT approved as a subfloor for hardwood flooring and must be removed prior to hardwood installation.
To summarize, here is a reference for floor materials and subfloors to be used at your house:
Hardwood -> OSB or regular plywood, minimum 23/32″, recommended 7/8″ or 1-1/8″
Tile -> OSB or plywood with layer of cement board or hardiback
Carpet -> OSB or plywood with particle board (optional) for softness.
| Top Layer | Hardwood | Carpet | Vinyl | Ceramic or Porcelain |
| Fastener | Nail, Float or Adhesive | Glue or Stretch | Glue or Float | Adhesive |
| Moisture Barrier |
Underlay Paper | – | Underlay Paper | – |
| SubFloor | OSB or Plywood | Particle Board,
MDF, HDF |
Any | Hardyback or Cement Board |
I have a mobile home and wanted to put porcelain tile 56” x 17” in front of a fireplace but the floor is particle board. I took out masonry brick out of the space so it stuck up high from the laminate floor. The surrounding laminate flooring is 5/8 thick and the porcelain tile is 3/8 thick. In Florida we don’t use the fire place more than 10 times a year. One seam in floor. I don’t want the porcelain tile sticking up much higher than the floor. So questions. 1) could I get away staying with the particle board floor 2) if I can use existing floor what is the thinnest cement board if I need one to use 3) what what would happen if I put the tiles straight on top of the existing floor? I appreciate your response.
Gary,
1) Not sure what you mean by that? Is particle board flooring is safe near the fire place?
2) You can use 1/4″ thick Hardiebacker board in order to get to the same level with laminate flooring. This is the best option.
3) If you install tiles over particle board, chances that you will see cracks in grout within one year are very high. Depending on cement/glue, tiles might last longer. We would not recommend this option for sure.
I have a tiny house and the flooring is osb, I was wanting to put down self adhesive stick on tiles as the flooring to go on top of the osb flooring. Would that be okay or do I need something in between the two? First time home owner so i do not know much about this stuff
Skyler, in general, you can apply stick on tiles right on top of OSB. Couple things to mention:
1) Make sure that all the OSB boards are leveled. If you see spots where one board is higher than the one next to it – sand it down a bit.
2) Consult with whoever you bought this material from. In general you don’t need to do any prep work or install additional sub floor, but some manufacturers would specify it in product description brochure, so read that one too.
3) Before installation, vacuum entire floor, do all the corners and closets to avoid any issues in the future.
We have a prefab house that has osb, particle board and then laminate flooring. Can I install hardwood directly on top or do I need to remove the laminate flooring and particle board to install the hardwood directly onto the osb
Hi Amanda,
Definitely remove both laminate and particle board. Also, check the thickness of OSB under the particle board, make sure it’s 3/4″+ thick. If not, you can add additional layer of OSB on top of existing one.
By the way, how do you like your prefab house? Any surprises you can share with our readers? Thanks! =)
Hi. We have a 70’s house with deep pile carpeting and particleboard underneath. Unfortunately, we have a cat that has started peeing in two spots. I want to pull out the carpet and put down a waterproof vinyl laminate to help deal with it (if not stop it entirely) and I’m wondering if I can put this laminate over the particleboard. I may have to pull out the boards that have been potentially affected by the urine but hoping to not have to pull all the boards. I did this in another room and it’s a royal pain.
Hello Annette,
Yes it’s fine to put laminate over a particle board. One important thing to mention here – your particle board has to be in good shape. Laminate floor perfectly repeats landscape of subfloor, so if your particle board is broken or not perfectly flat in some spots, it has to be fixed(sanded down or replaced). Overall we see it only in 5-10% of the cases, not more.
Also, check out cats related blogs… There are special technics you can follow to train your cat to use potty. I personally had similar issue with my cat, but was able to solve it in just about a week or so.
Best wishes to you and your furry friend =)
Hi, thanks for the article. Very informative. I have bought a place where the previous owner started to build out a subfloor in an attic. But he used 22mm particle board. It certainly needs stiffening with OSB as it’s creaky and I don’t think it would be strong enough. The question is whether the particle board needs removing or just to lay OSB over the top of it. Any advice ?
Hi Jon. Very interesting situation to be honest. Best case is to take particle board out, that’s 100%. But, if you lay OSB over it and nail it well, most likely it will be ok. It’s basically leads to the point of how much of an effort you’re willing to make. Want to make it right? – Take it out. Want to get it done fast – lay over it, but make sure to add extra nails. I say that there will be a very very little chance that it will be creaky after OSB goes over it.