Flooring question - house renovation

I bought a house back in April and I am slowly working on renovating it... One thing we are planning is hardwood in our master bedroom, which it turns out we couldn't do because we had particle board. So I ripped up all the particle board, which took forever. Once I got that up it exposed the pine plank subfloor from when the house was originally built. Some of it was in bad shape so I removed the approx 15 cracked ones.

So that is where I right now, getting ready to purchase new planks and then plywood to lay over it.

I have a few questions that I was hoping someone with much more experience can help me out with:

1) should I just remove all of the planks and go for a thicker plywood? (we have lowish ceilings so trying to save height if possible)
2) if I replace the planks, what type of plywood should I get. I was planning 1/2 inch but if thicker is better and not overkill. Also is there a specific grade? I'm not looking to shave every penny possible but not looking to overdo either
3) plywood should go perpendicular to the planks correct, offset each row and leave 1/8 gap between boards correct?

I will probably have more questions as I go, I appreciate any help you guys can give me.

View attachment 1448833005629.jpg

3/4 ply, then flooring. BTW, are those ceiling joists your nailing on ???

I have not started nailing anything, that picture is the current state before anything goes back on. Aren't floor and ceiling joists the same thing?? What likely looks odd in the pic is my house is a converted cape to gambrel colonial so the old and new joists are in there, lighter being new.

You should use 3/4" tongue and groove plywood. Since you have gone so far, just remove the rest of the planks.

If you want to keep the floor from squeaking, run a bead of construction adhesive (Liquid Nails or similar) along the top of each joist and on the edge of each tongue and groove joint. Those should run perpendicular to the joist spans. The 8' length of the plywood would run across the joists. Deck screws are best as they tighten down the plywood to the joist, but suitable nails are ok too.

+1^
Looks like you pulled up all the old floor boards already.
They may have been fir rather than pine. They're nice looking wood, but can be very, very splintery.

I'm not an expert in flooring but have done my fair share over the years. I think you'll need gripping nails to secure the plywood to the joists or perhaps better, drywall or decking screws.

Are those 6" joists? Is that bedroom in the attic?

Put in or upgrade all your electrical, plumbing, and heating before closing the floor. Also think of things like fans and light points for the room below.

IslandLizard said:

+1^
Looks like you pulled up all the old floor boards already.
They may have been fir rather than pine. They're nice looking wood, but can be very, very splintery.

I'm not an expert in flooring but have done my fair share over the years. I think you'll need gripping nails to secure the plywood to the joists or perhaps better, drywall or decking screws.

Are those 6" joists? Is that bedroom in the attic?

Put in or upgrade all your electrical, plumbing, and heating before closing the floor. Also think of things like fans and light points for the room below.

Click to expand...

++1 for the previous, previous poster.

+1 for @IslandLizard - take full advantage of the open spaces. Electrical, plumbing, hvac, network cables, coax (tv), etc. Plan the room below to it's maximum.

Also, note any problems with dry rot, etc. There might be hints of problems elsewhere in the property.

Neobrew - I read that tongue and groove is not recommended for hardwood, is that incorrect? So you suggest remove everything then plywood only? I am leaning that direction right now anyway to give a slightly higher ceiling will probably result in a mini step down from the hallway though.

Islandlizard- attaching a better pic of spacing. The old boards sure did splinter, I ripped up anything with more than a few inch splinter. I am already in the process of upgrading electrical and will be installing recessed in the rooms below (well my electrician, I'm not a fan of electrical work). Also not an attic but converted cape so it was maybe half the size originally, but done far before I owned it.

Forgot pic

View attachment 1448852746699.jpg

NeoBrew hit the nail on the head, pun intended,

insulate between floors.

need to run a cable? computer up grade? phone ?

tjmac5071 said:

Neobrew - I read that tongue and groove is not recommended for hardwood, is that incorrect? So you suggest remove everything then plywood only?

Click to expand...

I'm not aware of any issues with tongue and groove an hardwood floors. What is your source? I could certainly be unaware.

If all you have left are those few boards, I'd say start fresh. It will save you from having to figure out how to get everything leveled out.

If you have not already found this, here is some information on subfloors:

http://www.hardwoodfloorsmag.com/search-results.html?q=sub floor

this link is international code, i do not know if you are under n=uniforrm or international
but this is the MINIMUM required.
if you are thinking tile,,that will be 1 1/4 total
with 5/8 ply, 1/8 backer board and 1/2 tile


http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_5_sec003.htm



""""""j. Unsupported edges shall have tongue-and-groove joints or shall be supported with blocking unless minimum nominal 1/4-inch thick underlayment with end and edge joints offset at least 2 inches or 1.5 inches of lightweight concrete or approved cellular concrete is placed over the subfloor, or 3/4-inch wood finish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf.

k. Unsupported edges shall have tongue-and-groove joints or shall be supported by blocking unless nominal 1/4-inch-thick underlayment with end and edge joints offset at least 2 inches or 3/4-inch wood finish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf, except panels with a span rating of 48 on center are limited to 65 psf total uniform load at maximum span.""""""

Thanks for the help everyone. Gonna rip the rest of the boards up this weekend and do the plywood in a couple weeks. I'll update with some progress pics and likely more questions as the project continues

Not sure if anyone cares but the floor is down and very solid

View attachment 1468811528722.jpg

View attachment 1468811552847.jpg

Very nice! I like the floor color with the wall color.

looks great!

A little late but here's my two cents..
You will be happy w/ the extra effort you put to replacing the sub floor. It is possible to nail over particle board,just not ideal,staples or cleats don't have as good holding power in PB as the do in OSB or Ply . 3/4 ply is also standard as 1/2 can break down a lot faster and start squeaking.
All said and done you now have a solid subfloor and a very solid floor w/ the wide plank hickory.
I've been in the hardwood flooring trade for 28 years and seen a lot of poor installations done by homeowners,it may seem like a lot for what you did but it's better than having to live w/ a floor that moves and squeaks.