PILOT SPIN

Spin Zone => Spin Zone => Topic started by: asechrest on June 03, 2016, 07:24:55 AM

Title: Leveling a concrete slab
Post by: asechrest on June 03, 2016, 07:24:55 AM

I am laying a high-quality laminate floating floor in my first home. I am doing the work myself. For those not familiar, this is the click-lock type flooring that comes in planks and locks together. It's gone quite well, except for a spot in the living room. The flatness of the subfloor is an important factor in the success of laying a floating floor.  I say flat vs. level because uniformly out of level is fine, but changes in flatness beyond a certain tolerance are a problem. Too much variation in flatness can cause issues, including spots with a soft feel, and/or future problems with buckling or weakening of the locking mechanism.

Well, I've got a spot in the living room near the rear French doors that somehow I didn't notice before laying the floor.  I have one of two problems - a high spot a few feet from the door, and/or a sloping toward the door.  Sorta' like this, I think:   --^-...||.

This job has been interesting and I am happy to do it. I'm not sure I'd do it again, though.  So, has anyone had experience "leveling" a concrete floor?  Unfortunately I'd have to pull up about 12 rows of flooring to do it.  I know there is self-leveling compound but I have no experience with it. Plus, if what I have is a high spot rather than a low spot, I'm not sure if SLC is the answer.  Probably grinding down the high spot is what'd be needed then, and I'm not prepared to do that.

Would a concrete contractor be the best to hire if I wanted to take care of this?
Title: Re: Leveling a concrete slab
Post by: Little Joe on June 03, 2016, 07:32:20 AM
I am laying a high-quality laminate floating floor in my first home. I am doing the work myself. For those not familiar, this is the click-lock type flooring that comes in planks and locks together. It's gone quite well, except for a spot in the living room. The flatness of the subfloor is an important factor in the success of laying a floating floor.  I say flat vs. level because uniformly out of level is fine, but changes in flatness beyond a certain tolerance are a problem. Too much variation in flatness can cause issues, including spots with a soft feel, and/or future problems with buckling or weakening of the locking mechanism.

Well, I've got a spot in the living room near the rear French doors that somehow I didn't notice before laying the floor.  I have one of two problems - a high spot a few feet from the door, and/or a sloping toward the door.  Sorta' like this, I think:   --^-...||.

This job has been interesting and I am happy to do it. I'm not sure I'd do it again, though.  So, has anyone had experience "leveling" a concrete floor?  Unfortunately I'd have to pull up about 12 rows of flooring to do it.  I know there is self-leveling compound but I have no experience with it. Plus, if what I have is a high spot rather than a low spot, I'm not sure if SLC is the answer.  Probably grinding down the high spot is what'd be needed then, and I'm not prepared to do that.

Would a concrete contractor be the best to hire if I wanted to take care of this?

When I had my floor done several years ago, they used a thick insulating pad underneath and said that should take care of any problems I had.  I don't know how extreme your situation is, but I'd call a professional wood floor installer and ask his advice before calling a concrete contractor who may see a very lucrative opportunity in your naivety (no insult intended).  Where did you buy the flooring?  Can they offer advice?

I do hope you are using some sort of underlayment pad.  It makes a huge difference in noise dampening and insulation.  Floors can get cold.
Title: Re: Leveling a concrete slab
Post by: bflynn on June 03, 2016, 07:37:54 AM
Would a concrete contractor be the best to hire if I wanted to take care of this?

no, you should hire a Mexican.  What do you want, you meant to post this to the spin zone? ;)

You can do this yourself.  Water should tell you whether or not you have a high spot.  Lay a length of something rigid like gutter material across and see where the water collects, it worked for the Eqyptians.  Or you can get fancy with a rotating laser level. 

If you need the grinder, there should be many places that rent them - Home Depot probably has it.  You grind it down until you only have low spots.  Wear a mask and ear protection, it's not hard but it loud and dirty.

For the SLC, it's easy, basically you pour it out and it self levels.
Title: Re: Leveling a concrete slab
Post by: Bob Noel on June 03, 2016, 08:28:12 AM

For the SLC, it's easy, basically you pour it out and it self levels.

I haven't used a SLC, but unless the high spot is just too high, the SLC would seem to be the way to go.

I suspect a contractor would opt for a SLC.

Title: Re: Leveling a concrete slab
Post by: asechrest on June 03, 2016, 08:38:57 AM
When I had my floor done several years ago, they used a thick insulating pad underneath and said that should take care of any problems I had.  I don't know how extreme your situation is, but I'd call a professional wood floor installer and ask his advice before calling a concrete contractor who may see a very lucrative opportunity in your naivety (no insult intended).  Where did you buy the flooring?  Can they offer advice?

I do hope you are using some sort of underlayment pad.  It makes a huge difference in noise dampening and insulation.  Floors can get cold.

Thanks. I am using a premium underlayment with moisture barrier protection -- Floor Muffler Ultraseal. It does serve to smooth out some flatness issues but this area seemed to be too much for it.

I got the flooring from Floor and Décor.  Judging by their Saturday morning "class" on laying laminate/wood flooring, I don't have much confidence in their help. But I will ask.
Title: Re: Leveling a concrete slab
Post by: asechrest on June 03, 2016, 08:56:29 AM
no, you should hire a Mexican.  What do you want, you meant to post this to the spin zone? ;)

You can do this yourself.  Water should tell you whether or not you have a high spot.  Lay a length of something rigid like gutter material across and see where the water collects, it worked for the Eqyptians.  Or you can get fancy with a rotating laser level. 

If you need the grinder, there should be many places that rent them - Home Depot probably has it.  You grind it down until you only have low spots.  Wear a mask and ear protection, it's not hard but it loud and dirty.

For the SLC, it's easy, basically you pour it out and it self levels.

I'm really not looking forward to grinding. I understand it makes a horrid mess, too.  I'm hoping SLC will work.  I'm half-tempted to just leave it and pull it up at a later date if it balloons into a bigger problem. But I know I should take care of it now. :-\