Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Flooring

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 12-03-2008, 01:30 PM   #1
Newbie
 
Join Date: Sep 2008
Location: Virginia
Posts: 22
Share |
Default

Subfloor Condition - How Important?


Hi there,

I'm fixin' to install a cork floor in my bathroom, and I've posted loads of questions, and have gotten some great advice. I have one more (I tend to be descriptive, please forgive the length).

I'm going to install 12" x 12" cork glue-down tiles using DriTac 6200, which is what was recommended by the floor manufacturer. I've gone through and thoroughly read the instructions, but I am worried about the condition of my subfloor.

It is sound and stable - no wiggles or anything like that. There is one place where there is a slight hump (very slight) with just a bit of spacing (maybe 1/8") between two boards. There is also what appears to be a flaking white paint on the boards (not all over, just in some places). I've scraped off what I can.

My question is - does this sound okay to you guys? Do I need to completely sand off this white paint-like stuff? Is the slight hump a big problem (I understand there will be a slight hump in the floor)? Do I need to Portland cement the whole thing before I lay the tiles? Do I need to tear out this subfloor and put in a new one?

Basically, do subfloors have to be 100% perfect to ensure a perfect floor? Or are some flaws okay?

Many thanks!

Hillary

811Gibbon is offline   Reply With Quote
Old 12-03-2008, 02:07 PM   #2
Tileguy
 
JazMan's Avatar
 
Join Date: Feb 2007
Location: Troy, Michigan
Posts: 4,066
Default

Subfloor Condition - How Important?


Hi Hillary,

The condition of the subfloor is critical for a good installation. Any flaw will be magnified once covered with a flexible covering.

What type of subfloor do you have? You mentioned a gap between two boards. This sound to me that your subfloor is made of dimensional boards, and not plywood sheets. That isn't a suitable substrate to install direct to. What does the manufacturer say? What brand cork do you have?

Re-read the directions and check that your subfloor is correct structurally. You should fix the hump regardless if you add plywood or not. You said it's slight, so it'll only take you a "slight" amount of effort to repair. Sand the foreign matter off. It could be softened by the adhesive and then everything will be loose.

Jaz

__________________
Tile 4 You LLC Troy, MI

DITRA Installs - KERDI Watertight-Mold-Free Showers. I have NEVER made a mistake, I thought I did ONCE, but, I was WRONG! A+ BBB rating - est. 1987 - over 50 yrs. exp.
JazMan is offline   Reply With Quote
Old 12-03-2008, 02:16 PM   #3
Newbie
 
Join Date: Sep 2008
Location: Virginia
Posts: 22
Default

Subfloor Condition - How Important?


Hi Jaz,

Thanks so much for your quick response. I'm totally losing sleep over this, so I really appreciate the advice.

It is a plywood subfloor, which is (I'm 99% sure) original to the 1984 house. I'm using APC Cork, and both they and their recommended adhesive company (DriTac) say plywood is an approved subfloor.

Okay, so I should fix the hump? How in the world do I do that? I don't even know where to begin. I was thinking about using a Portland cement to kind of even things out, but then DriTac doesn't specify if Portland cement is acceptable on the subfloor.

Sorry for all the questions, and thanks so much to you and the many other experts on here who help the green DIYers like myself.

Thanks,

Hillary
811Gibbon is offline   Reply With Quote
Old 12-04-2008, 02:45 PM   #4
Tileguy
 
Bud Cline's Avatar
 
Join Date: Mar 2006
Posts: 10,162
Default

Subfloor Condition - How Important?


Let's everyone stop and stand in one place for just a minute.

WHY is the hump there? What is causing the hump?
Bud Cline is offline   Reply With Quote
Old 12-04-2008, 02:57 PM   #5
Member
 
Floorwizard's Avatar
 
Join Date: Dec 2003
Location: Alaska!
Posts: 1,522
Default

Subfloor Condition - How Important?


Quote:
It is a plywood subfloor
If it's original subfloor, it is probably not approved substrate for Cork tiles.
You will need Underlayment. AC grade.
You may have it, but you will need to check for sure.
Anytime you glue down something, then any irregularity will come up thru it.
Floorwizard is offline   Reply With Quote
Old 12-04-2008, 03:02 PM   #6
Tileguy
 
JazMan's Avatar
 
Join Date: Feb 2007
Location: Troy, Michigan
Posts: 4,066
Default

Subfloor Condition - How Important?


You're right, plywood is an approved underlayment. I was worried your subfloor was dimensional lumber like 1x6's or (?) since you called your underlayment "boards" instead of "sheets". OK, you're fine if it's an underlayment and not the subfloor. do you have 2 layers of plywood?

Can you describe this hump? How large, how high above the rest of the floor? Take a long straight edge and see what you get. Humps can be difficult to correct, but it's worth looking into it.

Jaz
__________________
Tile 4 You LLC Troy, MI

DITRA Installs - KERDI Watertight-Mold-Free Showers. I have NEVER made a mistake, I thought I did ONCE, but, I was WRONG! A+ BBB rating - est. 1987 - over 50 yrs. exp.

Last edited by JazMan; 12-04-2008 at 03:08 PM.
JazMan is offline   Reply With Quote
Old 12-04-2008, 03:06 PM   #7
Newbie
 
Join Date: Sep 2008
Location: Virginia
Posts: 22
Default

Subfloor Condition - How Important?


Hahaha, great question about the hump! Very basically, our house (and several others in our complex) has several irregularly sized joists running through it (rather than, like 14" deep, these are all 15" deep, something like that). There were three in the front of the house that were causing some real problems, and we actually just had those completely torn out and replaced. The only real symptom from this joist in the bathroom is the slight hump in the floor. It's not a big enough concern to me to pay the small fortune required to have this one ripped out and replaced as well. Does that make sense?

Eeek, I need to fix my language...boards vs. sheets. You're right, though, they are sheets, not boards.

I bought some Portland cement last night, and I'm going to just go ahead and skim coat the plywood tonight, just to make sure I've filled in all of the little cracks and holes. It isn't that hard, and it will just make me feel better. The glue is approved for use on both plywood and Portland cement, so...fingers crossed!
811Gibbon is offline   Reply With Quote
Old 12-04-2008, 03:13 PM   #8
Tileguy
 
JazMan's Avatar
 
Join Date: Feb 2007
Location: Troy, Michigan
Posts: 4,066
Default

Subfloor Condition - How Important?


Hopefully you bought a patching or skimming products that contains Portland, not just plain ol' Portland. And it's made to stick to plywood for this purpose, right?

Jaz
__________________
Tile 4 You LLC Troy, MI

DITRA Installs - KERDI Watertight-Mold-Free Showers. I have NEVER made a mistake, I thought I did ONCE, but, I was WRONG! A+ BBB rating - est. 1987 - over 50 yrs. exp.
JazMan is offline   Reply With Quote
Old 12-04-2008, 03:17 PM   #9
Newbie
 
Join Date: Sep 2008
Location: Virginia
Posts: 22
Default

Subfloor Condition - How Important?


There I go again, using the wrong terminology! Yup, I sure did. I've used it before on plywood subfloor, so I'm pretty sure I bought the right thing. I'm definitely posting pictures when (and if) I get this all done.

Thank you again to everyone who wrote back.
811Gibbon is offline   Reply With Quote
Old 12-04-2008, 03:20 PM   #10
Tileguy
 
Bud Cline's Avatar
 
Join Date: Mar 2006
Posts: 10,162
Default

Subfloor Condition - How Important?


OK! How deep do you want to go with this? Sounds like the "hump" is a result of a floor joist that was installed with a reversed crown. Common problem. You may be able to fix this one yourself if you so choose and you won't have to remove the whole floor joist to fix it.
Bud Cline is offline   Reply With Quote
Old 12-04-2008, 04:25 PM   #11
Newbie
 
Join Date: Sep 2008
Location: Virginia
Posts: 22
Default

Subfloor Condition - How Important?


Hi Bud,

Hehehe, well, I know this is not the right answer at all, but it depends on how complicated/expensive/time-consuming it is. I'm all about trying my best to level out the plywood subfloor a bit so that the screwed up joist doesn't mess my floor up too much. But, truth be told, the hump is in a back corner of the bathroom, and it doesn't bother me much.

I'm not skilled enough to take out and install a new subfloor (nah, I could probably do it, I just don't have the right tools at all). So, if I had to lift out the subfloor to get to the joist, I'd be in some trouble.

That and this bathroom mini-renovation is already one month over the planned time, and my in-laws are coming for Christmas. I've spent too much money, and my husband might just kill me if I tell him we need to fix the hump.

So, given that, should I fix the hump or learn to love it?
811Gibbon is offline   Reply With Quote
Old 12-04-2008, 05:12 PM   #12
Tileguy
 
Bud Cline's Avatar
 
Join Date: Mar 2006
Posts: 10,162
Default

Subfloor Condition - How Important?


OK, GOTCHA! You don't have to learn to love it, maybe just having a slight affection for it will suffice.

Let's move on.

Bud Cline is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Ground / neutral reverse. Important or not? Deck Electrical 8 07-09-2008 07:59 PM
How important is plastic vapor barrier on foundation wall? slatergrl Remodeling 5 02-18-2008 12:49 PM
four important reasons wood-butcher Carpentry 2 10-09-2006 06:08 AM
Important about Generators Mike772 Electrical 8 04-29-2006 04:50 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.