User Name
Password
AppleNova Forums » AppleOutsider »

Laying hardwood flooring


Register Members List Calendar Search FAQ Posting Guidelines
Laying hardwood flooring
Thread Tools
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-10, 15:26

Anyone here have experience laying hardwood flooring down on 3/4" plywood subfloor? Any tips or things I need to think about?

I know there are tons of videos and guides out there but I'm not really interested in random searches when I might have someone with direct experience here. Basically the office in my house was part of the garage. The floor sits roughly 7" lower than the rest of the house. The door into the space is level with the main floor.

I figure I'll build a 2x6 subfloor (16" centers) with 3/4" T&G plywood subfloor. That is just about perfect for making this floor line up with the main floor. The measurements for actual thickness almost line up perfectly. There will be a threshold to handle the transition so it shouldn't be a problem there.

The real questions are all the specifics on actually getting the flooring in. I'm going to buy a framing gun since I can use it for other projects. That will handle the sub-frame. Laying plywood is generally easy and I'm planning to screw it to the framing. The flooring I'm looking at is the pre-finished hardwood so we don't have to sand and stain in the house.

So anyone do this already? Any insights on how to go about it? Odd things I should really think about first?

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-10, 15:37

How far are those 2x6's running?
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-10, 15:53

8'. There will be a "joint" where I put a another 4' because there is a 13' stretch. The extra foot will be framed for a vent duct.

To be more specific, the room is "U" shaped because there is a "closet" under the stairs that lead to the FROG. That closet is 4' and the main floor of the office is 8' beside it. There is one area that is 10' x 13' at the end.

Edit: super rough layout of the space. The left side is the closet under the stairs.


Edit2: the subframe will sit on a slate floor that is on concrete that is 8" thick. (Remember, was a garage and they put extra concrete into this place.)

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.

Last edited by turtle : 2020-09-10 at 16:08.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-10, 16:17

2x6 joists over 8 feet? They're going to sag/wiggle on you over time, and that could result in buckling.

1) Generally, dimensional joists are rated to 1 foot of run for every 1 inch of dimension, so a 2x6 is good to cover 6 feet-ish. I would use 2x8 under there if you could, and 2x6 where it runs 4 feet.

2) Make sure you climatize your flooring for a minimum of 1 week in the space where they are going to be installed. Too high moisture content and they will shrink as they dry out, leaving exposed seems. Too low moisture content and they will buckle as they absorb moisture. This is really important if you want the surface to last. My preference would be 2-4 weeks acclamation time.

3) Rent a floor nailer from a tool rental store. They are not cheap, and you will only (hopefully) need it once.

4) Be sure to leave a 1/4" gap around the walls to allow for contraction/expansion.

5) When cross-cutting oak floor, be sure the saw blade is cutting *up* into the exposed surface to avoid tear-out. If using a miter saw, the exposed surface should be up (facing toward you); if a circular saw, make sure the exposed surface is facing down (facing away from you).

6) For your 3/4 ply, tongue and groove is best. Use subfloor glue between the ply and the joists, and fasten it down with 2" coated deck screws to reduce squeaking and rust.

7) If your crawl space is humid, apply vapor barrier between the ply and the flooring.

I'll update this post as more thoughts jump into my head.

- AppleNova is the best Mac-users forum on the internet. We are smart, educated, capable, and helpful. We are also loaded with smart-alecks! :)
- Blessed are the peacemakers, for they shall be called sons of God. (Mat 5:9)

Last edited by kscherer : 2020-09-10 at 18:45. Reason: added "dimensional" for clarification
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-10, 16:28

Check the edit2 of my post. Thankfully I don't have the sagging problem but the 2x6 is actually raising the floor as opposed to just supporting it. There is actually basement space under the 8" of concrete.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-10, 17:13

OK. Then you're just fine. In fact, you could use 2x4's, but I assume you're matching floor height somewhere else? Also, you gonna insulate in there?

You will absolutely need a vapor barrier between the concrete and anything that goes on it. So, 4 mil plastic down first, then your joists, ply, and flooring. Insulate if you want a warmer feel.

Concrete will suck moisture from way over there and you will get build-up in that air space unless you put in vapor barrier. It would take time, but it will happen, and that could lead to mold on the underside of the ply.

- AppleNova is the best Mac-users forum on the internet. We are smart, educated, capable, and helpful. We are also loaded with smart-alecks! :)
- Blessed are the peacemakers, for they shall be called sons of God. (Mat 5:9)
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-10, 17:19

Oh wow. I didn't think about that. Even though there is a basement area under the floor I should still do the vapor barrier? I was planning to skip it given this isn't concrete on dirt. The exterior edge of the concrete I'm sure contacts dirt, though there is a French drain around it.

I'm not planning to insulate because I like it on the cooler side. I guess I should consider it though given it isn't only going to be me...though it will be while I live here.

All the other tips are awesome and certainly will look at implementing them too. Thanks for taking the time to post them. I wasn't thinking I would need the gap on the ends but I also didn't think about expansion/contraction. See how novice at this stuff I am.

I might be capable, but I'm ignorant and know it.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-10, 17:24

Here is a fun question; how do I know how many screws to buy? What is considered good spacing on the subfloor?
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-10, 17:27

Quote:
Originally Posted by turtle View Post
Oh wow. I didn't think about that. Even though there is a basement area under the floor I should still do the vapor barrier?
Concrete is porous and draws moisture from anywhere and everywhere, including right out of the air. No contact with the ground will drastically reduce this effect, but it will still occur, especially if your area is humid. A/C will dry the air during the warm months, but heating will wet it during the cold months. You don't want moisture to reach anything organic or untreated (mold only grows on organic surfaces, and requires moisture). Which brings up one more thing: Is the concrete surface bare, or has it been painted? I ask because most paints contain organic materials and will attract mold.

Quote:
Originally Posted by turtle View Post
Here is a fun question; how do I know how many screws to buy? What is considered good spacing on the subfloor?
Screws are sold by the pound. For sub floor, the edges should get a screw every 8 inches, and the centers every 12 (roughly 30 screws for a 4x8 sheet on 16" centers). Smaller boxes are less efficient price-wise, but you also don't want a million of them left over. For a job that size, start with a 5 pound box and see how far it goes.

- AppleNova is the best Mac-users forum on the internet. We are smart, educated, capable, and helpful. We are also loaded with smart-alecks! :)
- Blessed are the peacemakers, for they shall be called sons of God. (Mat 5:9)
  quote
drewprops
Space Pirate
 
Join Date: May 2004
Location: Atlanta
 
2020-09-10, 18:35

Okay this is fascinating. I will have some questions for a different smaller project soon!
Carry on, don't mind me.
...
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-10, 18:44

I will treat you as the speck that you are!

  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-11, 09:32

I walked down the screw isle and was overwhelmed. Holy crap there are about a gazillion options!

I have a 25lbs bucket of drywall screws that I was planning to use. They suck and I shouldn't use them, plus there are only 1 5/8" long. Do you have a recommended screw? Lowe's preferably since it is likely where I'm going to buy my supplies from.

For the adhesive between the joists and plywood, do you have a preferred brand? I used Loctite PL Premium for the dance floor and it seems fine. I guess what I'm really wondering is am I after silicone adhesive to soften the contact or adhesive to bond it?

Edit: BTW, this is the flooring it is covering. I know I'm likely to have a little challenge where the slate isn't level. That lack of smooth level is one of the reasons I want to raise my floor and replace the existing flooring. I'm just going to build right over the top of this flooring.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.

Last edited by turtle : 2020-09-11 at 09:48. Reason: Added pic of existing floor.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-11, 09:53

Screws: https://www.lowes.com/pd/Fas-n-Tite-...-lb/1001062884

Don't use sheetrock screws. They corrode over time and, since floors get spilled on, moisture will get in there. Once they begin to corrode they will start squeaking.

Glue: https://www.lowes.com/pd/LIQUID-NAIL...hesive/3365546

The purpose is to fasten it down tight. The subfloor and the joists should act as one piece. Put a thin bead (1/4") down the entire length of the joist, right down the center. Do not "spot weld". Make sure the "rough" side of the plywood is facing down.

Also, buy several packs of shims and shim the joists level. Find the high spot in the floor and work from there.

- AppleNova is the best Mac-users forum on the internet. We are smart, educated, capable, and helpful. We are also loaded with smart-alecks! :)
- Blessed are the peacemakers, for they shall be called sons of God. (Mat 5:9)
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-13, 09:56

I've added a 360 laser level to my cart to help me get that level right. I've also added two packs of shims. Even if I don't need all of them, if I have extras I'll be able to use them for other projects and such.

Thinking about the sheetrock screws I'm really hoping that doesn't end up an issue in the dance floor build. The good part is there are very few screws used in that build and I can easy pull up the flooring and replace the screws if needed down the road.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
Matsu
Veteran Member
 
Join Date: May 2004
 
2020-09-13, 15:52

Maybe I’m missing something. Was this room once a garage? Most garages here are a 4” concrete slab on a crushed base floating between 48-60” deep concrete footings that were poured as part of the home foundation. Even where the home has a basement - most do - there is no basement under the garage floor. If this is your config, outright strength isn’t going to matter, but cold/moisture and “slope” will. Most garages slope towards the bay door to help ice/snow melt and clean up run out. It’s slight, but it’s too much for a living space floor, and so it has to be levelled, but anything you build overtop is going to be plenty strong if it’s sitting on a concrete slab.

When I prepped our interior subfloor for prefinished hardwood, I ripped out all the tile and parquet, and bought a big tub of construction screws and did a little overkill, putting them down every 4” on every joist.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-13, 21:49

Quote:
Originally Posted by Matsu View Post
putting them down every 4” on every joist.


Dude!
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-14, 08:39

Yeah, this garage really does have a full basement under it. There is an I beam down there that you would normally see under a bridge. It is positively massive.

The level is a little concern for me given that slope you mentioned on top of the uneven design of this flooring. I'm thinking/hoping that the couple we bought it from took care of that when they put the slate down on the floor in here, but I bought four packs of shims to help as needed. I'm also planning to layout the joists to check for level before I start nailing them. I thought about ripping up the slate, but it doesn't seem worth the effort when as it is I'll align almost perfectly with the main floor's floor.

Yesterday I ordered the lumber and got most of the supplies I needed. I even bought a nailer and 4000 3" framing nails. It was only $5 more than the 2000 I was going to buy. I had a coupon from Home Depot and Lowe's went ahead and matched it for 15% off. Only one item (special order) wasn't discounted. Better than having to shop at Home Depot. The one here has such horrible customer service. The delivery is set for the 28th though. I don't have a vehicle that can carry 11 3/4" T&G plywood and I'm good with having them deliver it.

As long as I can get this floor done for under $6000 I'll be happy. That is the first quote from the contractor before he forgot that number and said it was $6800.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
Matsu
Veteran Member
 
Join Date: May 2004
 
2020-09-14, 09:54

Wow. That’s kinda cool. Just so I understand, you have a reinforced concrete slab sitting on an oversized structural beam with conditioned space both above and below?

Certainly weight and strength should not be a problem for something designed to hold 6000 lbs or so per bay.

I would probably rip out the slate. I’m a bit of a masochist, but... if it degrades over time and some tiles come loose and start to rock, you’re going to hear creaking/grinding and it will piss you off that you can’t get to it.
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-14, 10:49

Quote:
Originally Posted by Matsu View Post
I would probably rip out the slate. I’m a bit of a masochist, but... if it degrades over time and some tiles come loose and start to rock, you’re going to hear creaking/grinding and it will piss you off that you can’t get to it.
Yeah, I'm going to second that.
  quote
Matsu
Veteran Member
 
Join Date: May 2004
 
2020-09-14, 13:27

I'm may be being a little hypocritical here. I have a glossy white 12" ceramic basement floor left by the previous owner. It's pretty basic, but very easy to keep clean. Ceramic and especially porcelain are very effective vapor barrier, but they won't stop flooding, naturally. They are however cold to walk on. I've been analyzing a basement reno and am tempted by some of the solid vinyl flooring systems that can lay right over. I found some stuff that is a dense solid vinyl all the way through and is just 7mm think. It's molded, not printed, with a grain pattern out of solid color that runs all the way through the tile. It's even convincing to the touch. Someone I know laid it over her basement tiles and it looks good. Her installer said there was no need to fill the grout lines because the material is very dense and will not "sink". I'm not so sure. I want to wait a few years and see if the grid pattern from her tiles shows through.

I feel like it's a little different if you're floating a floor over something bonded to a slab on or below grade, but perhaps I should heed my own advice, or at the very least spend the time filling the grout lines with synthetic self-leveling compound?

.........................................
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-14, 13:45

In your case I would totally fill the grout lines. I had LVP in my last house and it will meld to the imperfections of the floor below it over time. I'm not sure how wide the gap would need to be, but I can say mine did for some imperfections we didn't correct on the slab it was on at the old house.

For mine I'm not convinced I need to remove the slate. On one hand I can see why I should, on the other it seems less likely to be a problem than the likelihood of it being one. Mrs T says we should remove it though.

Matsu, you are correct that I have climate controlled space above and below the floor I'm building the raised floor on. I was going to get a picture of the space below, but it is storage and I just can't bring myself to snap a picture of that. Apparently the original owner (who had it custom built) put an extra $30,000 into the basement concrete and supports because he didn't want the house to go anywhere. I was told that this floor is 8" of concrete but I just measured it and it is 6" with 7" where it dips with the corrugated metal bottom. There is supposed to be rebar in there too, but I'm not cutting in to find out. Under the corrugated metal forms there are steel trusses and one massive I beam with a steel support structure for it too. Yeah, this floor is going nowhere.

Louis L'Amour, “To make democracy work, we must be a nation of participants, not simply observers. One who does not vote has no right to complain.”
Visit our archived Minecraft world! | Maybe someday I'll proof read, until then deal with it.
  quote
turtle
Lord of the Rant.
Formerly turtle2472
 
Join Date: Mar 2005
Location: Upstate South Carolina
 
2020-09-14, 15:31

Looking up the process for removing the slate:
Quote:
Removing slate is challenging, difficult labor. It is bonded with cementitious mortar, which is quite hard, and there could be a few other layers of material to work through before you expose the original substrate. Broken slate has razor-sharp edges, and prying it up can send small particles flying.


Wonder how much it will cost to pay someone to remove the slate flooring...
  quote
kscherer
Which way is up?
 
Join Date: Aug 2004
Location: Boyzeee
 
2020-09-14, 15:42

More than it will cost to do it yourself.

  quote
Matsu
Veteran Member
 
Join Date: May 2004
 
2020-09-15, 07:30

I think you might be surprised pulling up the slate tiles. I’ve only ever pulled up ceramic from wood sub floor. And it’s not so much the tile that’s hard to get at, but the steel screen embedded in the skim coat and stapled down to the plywood that’s a bear. Tiles on a sufficiently thick concrete slab might come up easier once you break them up. Get a few cold chisels, I dismantled a raised stone hearth and reset it flush and the chisels and a mallet made quick work of a 3” thick hearth stone.

Last edited by Matsu : 2020-09-15 at 08:03.
  quote
Posting Rules Navigation
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Post Reply

Forum Jump
Thread Tools
Similar Threads
Thread Thread Starter Forum Replies Last Post
Anyone have any real-world experience with resilient flooring? psmith2.0 Creative Endeavors 7 2009-07-26 22:18
Laying Tile: Advise Please midwinter AppleOutsider 32 2006-03-16 20:32


« Previous Thread | Next Thread »

All times are GMT -5. The time now is 10:16.


Powered by vBulletin®
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2024, AppleNova