Basement subfloor questions

retired guy 60 · 09-01-2010, 04:42 PM

"I personally think studding and sub flooring below grade slab is a big mistake when there are plenty of materials that can go directly over the slab......"

I could not agree more. I just put down ceramic tiles in my basement using thinset right over the cement with no worries about sleepers, plywood, cement backer board, mold, or moisture. Last year I did one small room in the basement the same way and the tiles look good and are perfectly secure. Why look for extra work and risk moisture problems using wood or laminate when ceramic works fine (unless you hate ceramic for some reason)? Prior to this I had glued down carpet and it was nothing but a dust magnet. Plus when it got wet it held water like a sponge.

Aaroncarpet · 09-01-2010, 05:53 PM

well its one thing to get carpet wet, and another thing to have a moose pisss in your basement....strange things happen in moose territory.....I was once paddling in a river and spotted what I thought was a log.... 10 seconds later a moose shriveled out of the river bed and the "log" was antlers

Aaroncarpet · 09-01-2010, 08:36 PM

Jazman....don't worry, you won't have to repair it......I come from Michigan... I know about the basement.....better off to tell em its gonna be fine.....more money for the trades...If you are going to pay me to do a bunch of stuff that doesn't work, I'll take the money , I'll be in California by the time its all screwed up....

BTW Jazman ...are you familiar with Fairway Tile and carpet in Clawson MI....down the road from you on 14 mile.....that's where I learned to install

CyFree · 09-02-2010, 11:56 AM

Because we've been working mainly with basements for over 20 years and that is the bulk of our business, I believe we have a pretty good idea of what works and what doesn't.

We ripped enough rotten wooden floors, subfloors and moldy carpets to know one thing... none of them work.

JazMan might not have expressed himself as successfully and he expected but he is correct when he says that you should not use wooden subfloors, furry strips over the slab.

Actually, if you want to finish your basement and never have to do it over, you should avoid everything that is made with organic compounds, because basements, even when they look dry, always have some level of ground moisture infiltrating the below grade walls through capillary action.

Combine that moisture with wood and organic materials and you have the perfect conditions for mold and rot to develop.

Placing a poly sheet as vapor barrier straight against the slab will not help much, because it will only trap the moisture underneath and there is no saying what will happen under that poly sheet overtime.

Furthermore, according to recommendations issued by the U.S. Department of Energy in its Building America's Best Practices series, basement walls and slab should be allowed to dry to the inside of the basement, somehow.

In addition, keep in mind that a vapor barrier would only address the moisture from the slab. But basements get water from more sources than that. Think plumbing leaks, sump pump meltdown, leaky water heaters, burst washing machine hoses, an accidentally overflown toilette.

Any of those things happen and you will have a stinky and very moldy basement because, according to the Environmental Protection Agency, any organic material that doesn't completely dry in 48 hours will develop mold.

And when that happens, also according to that agency, you will need to rip it all off and discard because there is no 100% effective way to remove mold from things like wood, carpet, paper, cardboard, fiberglass and drywall.

So, what is the alternative? There is, of course, tile and stained concrete.

But if you are looking for something warmer, more affordable and less messy to install, I recommend you look into flooring options that are specifically engineered to work with basements.

They are mainly floating floors, (tiles and laminates) with interlocking features. They can be removed and replaced as needed. They are 100% inorganic and 100% waterproof. They have vapor barrier that, along with the finished surface, is raised a few centimeters from the floor by a system of channels or pegs that will allow the air to circulate underneath and dry the slab, as recommended by the Department of Energy, while offering moisture and some level of thermal protection as well.

Hope it helps.

retired guy 60 · 09-02-2010, 01:20 PM

CyFree, thanks for a nicely stated and logical explanation that makes sense.

Aaroncarpet · 09-02-2010, 07:33 PM

I was trying to pretty much say the same thing...Hope I haven't offended anyone....

57_Hemi · 09-19-2010, 09:13 AM

Quote:

Originally Posted by CyFree

They are mainly floating floors, (tiles and laminates) with interlocking features. They can be removed and replaced as needed. They are 100% inorganic and 100% waterproof. They have vapor barrier that, along with the finished surface, is raised a few centimeters from the floor by a system of channels or pegs that will allow the air to circulate underneath and dry the slab, as recommended by the Department of Energy, while offering moisture and some level of thermal protection as well.

Hope it helps.

Cool!

Great explination.....Thank You

I know that helped with my previous question.......

rookie_diy · 09-24-2010, 11:53 PM

what i gather from this discussion is that ceramic tiles and laminate should go directly on the concrete floor without even a vapor barrier???

adamsparkes · 09-25-2010, 11:38 AM

You guys ever hear of delta membrane?
Appartently you lay in right on the concrete then attach plywood to it or you can lay laminate right on top of the membrane let me know if anyones heard of this method

retired guy 60 · 09-25-2010, 05:10 PM

Quote:

Originally Posted by rookie_diy

what i gather from this discussion is that ceramic tiles and laminate should go directly on the concrete floor without even a vapor barrier???

Ceramic tiles are applied directly to the basement floor with thinset. Ordinary laminate is not a good choice for the basement due to water and moisture issues but CyFree indicates that there is a version that is acceptable. I am not familiar with the product he is referring to. For durability, I think ceramic is a wise choise...just my opinion.

rookie_diy · 09-25-2010, 10:15 PM

i am doing it half and half. i just purchased 12mm laminate flooring. it is not mentioned on the box that its AC3 but the HD guy assured me that they carry nothing less than that. he also suggested that the cork underlayment was the best option for the underpad. any suggestions whether its needed or i just go with a vapor barrier???

retired guy 60 · 09-26-2010, 02:48 PM

[quote=rookie_diy;507190]" he also suggested that the cork underlayment was the best option for the underpad. any suggestions whether its needed or i just go with a vapor barrier???"
Cork is an organic material and organic materials are subject to mold. I think this needs to be researched. I like Home Depot but sometimes the advice offered may not be correct. Little mistakes often result in major remedial projects.

rookie_diy · 09-29-2010, 09:39 AM

from all the comments and different opinions, seems like it is safer to just put the laminate directly on the concrete. after all, laminate is supposed to be inorganic and "engineered" to resist damage due to moisture. saves money and peace of mind...

Starlight · 10-01-2010, 11:18 AM

Is it a good idea to use a concrete sealer in cases like this, to reduce the amount of moisture coming up through the floor?

rusty baker · 10-01-2010, 11:32 AM

[quote=retired guy 60;507409]

Quote:

Originally Posted by rookie_diy

" he also suggested that the cork underlayment was the best option for the underpad. any suggestions whether its needed or i just go with a vapor barrier???"
Cork is an organic material and organic materials are subject to mold. I think this needs to be researched. I like Home Depot but sometimes the advice offered may not be correct. Little mistakes often result in major remedial projects.

One thing you have to remember about Home Depot, Lowes etc. Their employees are not trained in special fields. I have seen customers given the wrong advice many times by well-meaning employees who simply didn't know any better.

09-01-2010, 04:42 PM	#16
retired guy 60 Member Join Date: Jun 2009 Posts: 287	Basement subfloor questions "I personally think studding and sub flooring below grade slab is a big mistake when there are plenty of materials that can go directly over the slab......" I could not agree more. I just put down ceramic tiles in my basement using thinset right over the cement with no worries about sleepers, plywood, cement backer board, mold, or moisture. Last year I did one small room in the basement the same way and the tiles look good and are perfectly secure. Why look for extra work and risk moisture problems using wood or laminate when ceramic works fine (unless you hate ceramic for some reason)? Prior to this I had glued down carpet and it was nothing but a dust magnet. Plus when it got wet it held water like a sponge. Last edited by retired guy 60; 09-01-2010 at 04:43 PM. Reason: grammar

09-01-2010, 05:53 PM	#17
Aaroncarpet floor_whore Join Date: Aug 2010 Location: California, USA Posts: 74	Basement subfloor questions well its one thing to get carpet wet, and another thing to have a moose pisss in your basement....strange things happen in moose territory.....I was once paddling in a river and spotted what I thought was a log.... 10 seconds later a moose shriveled out of the river bed and the "log" was antlers __________________ A hundred yards a day (residential), keeps the bill collectors away....

09-01-2010, 08:36 PM	#18
Aaroncarpet floor_whore Join Date: Aug 2010 Location: California, USA Posts: 74	Basement subfloor questions Jazman....don't worry, you won't have to repair it......I come from Michigan... I know about the basement.....better off to tell em its gonna be fine.....more money for the trades...If you are going to pay me to do a bunch of stuff that doesn't work, I'll take the money , I'll be in California by the time its all screwed up.... BTW Jazman ...are you familiar with Fairway Tile and carpet in Clawson MI....down the road from you on 14 mile.....that's where I learned to install __________________ A hundred yards a day (residential), keeps the bill collectors away.... Last edited by Aaroncarpet; 09-01-2010 at 08:44 PM.

09-02-2010, 11:56 AM	#19
CyFree Below Grader Join Date: Jul 2008 Location: Seymour Posts: 68	Basement subfloor questions Because we've been working mainly with basements for over 20 years and that is the bulk of our business, I believe we have a pretty good idea of what works and what doesn't. We ripped enough rotten wooden floors, subfloors and moldy carpets to know one thing... none of them work. JazMan might not have expressed himself as successfully and he expected but he is correct when he says that you should not use wooden subfloors, furry strips over the slab. Actually, if you want to finish your basement and never have to do it over, you should avoid everything that is made with organic compounds, because basements, even when they look dry, always have some level of ground moisture infiltrating the below grade walls through capillary action. Combine that moisture with wood and organic materials and you have the perfect conditions for mold and rot to develop. Placing a poly sheet as vapor barrier straight against the slab will not help much, because it will only trap the moisture underneath and there is no saying what will happen under that poly sheet overtime. Furthermore, according to recommendations issued by the U.S. Department of Energy in its Building America's Best Practices series, basement walls and slab should be allowed to dry to the inside of the basement, somehow. In addition, keep in mind that a vapor barrier would only address the moisture from the slab. But basements get water from more sources than that. Think plumbing leaks, sump pump meltdown, leaky water heaters, burst washing machine hoses, an accidentally overflown toilette. Any of those things happen and you will have a stinky and very moldy basement because, according to the Environmental Protection Agency, any organic material that doesn't completely dry in 48 hours will develop mold. And when that happens, also according to that agency, you will need to rip it all off and discard because there is no 100% effective way to remove mold from things like wood, carpet, paper, cardboard, fiberglass and drywall. So, what is the alternative? There is, of course, tile and stained concrete. But if you are looking for something warmer, more affordable and less messy to install, I recommend you look into flooring options that are specifically engineered to work with basements. They are mainly floating floors, (tiles and laminates) with interlocking features. They can be removed and replaced as needed. They are 100% inorganic and 100% waterproof. They have vapor barrier that, along with the finished surface, is raised a few centimeters from the floor by a system of channels or pegs that will allow the air to circulate underneath and dry the slab, as recommended by the Department of Energy, while offering moisture and some level of thermal protection as well. Hope it helps.

09-02-2010, 01:20 PM	#20
retired guy 60 Member Join Date: Jun 2009 Posts: 287	Basement subfloor questions CyFree, thanks for a nicely stated and logical explanation that makes sense.

Basement subfloor questions