[SR996]

My basement slab required partial removal 5 years ago:furious:. The new slab portion is approximately 1/4 inch higher in certain areas. The contractor attempted to transition this ridge with leveling compound, feathered about 4-5 inches. Some of this work has begun to crumble, and I have removed most of it. What product do I use to level out this area, and how far does it need to be feathered back. Self leveling compound will not work as the pitch is in the wrong direction (to the sump pump).

Thanks in advance.

 

[Mudd]

There are many products that basically do the same thing. A height difference of 1/4" should be feathered out a couple feet, not just inches.

Off the shelf at Home Depot is Armstrong S-183 and S-184. It's been a while since I picked up a sack of either but I think the 183 is the grittier one for deeper fills and the 184 is finer for skimming.

If it was me, I'd build it up most of the way with the 183 and finish with the 184.

Mapei also makes similar products, and there are other brands.

 

[gma2rjc]

Mudd, would SR996 need to put down a bonding agent on the old cement before pouring the new?

 

[Mudd]

gma2rjc -

Most floor patches stick pretty well without primers or bonding agents. Most patches, especially the ones for feather finishing, have a lot of additives.

I took a class once where we checked out how primers affect bonding and it was kind of funny because most products we checked out stuck better without the primer than with it...

SR996 does mention the existing patch crumbling but who knows what was used, or even if it was floor patch.

I think it'd be more important to get the area nice and clean; after chipping/scraping/wire brushing/grinding, I'd mop the area with vinegar and water (ratio of about 1/2 cup distilled white vinegar to 1 gallon water) and let it sit a while. The acetic acid in vinegar is weak but will lightly "etch" the area and is good at removing glue residues.

Do the mopping well before the patch work so it has a chance to dry.

 

[SR996]

Thanks for the tip. I do not know what they used for patching the area. But, as my other post on this forum, the stuff was later painted with a latex floor paint. So, not only do I have to chip out the patch, I will also scrape off the paint . The scraper is faily aggressive and leaves a rough surface - bonding should therefore not be an isue? The area will be carpeted afterwards, and I do not want to see a ridge in the carpet. Does the patch have to be layered, or can the entire 1/4 inch be done in one coat? Also, should the patch "mend" the two slabs, or will the two edges merely continue to crack?

Thanks again.

 

[Mudd]

SR996 -

If you're going with carpet and pad, it's a lot more forgiving than if you were laying vinyl, for example... with carpet it doesn't have to be nearly as smooth.

Ardex Feather Finish can go up to 1/2" inch in one application if you believe the bag.

I don't know if that is sold at the big box stores, but Home Depot carries the S-183. I think it's a 1/4" max per application if my memory serves me correctly. You may want to build part way up and do a second application.

Knowing that you're doing carpet, I'd skip the S-184 (I guessed you were doing vinyl in your first post); it doesn't have to be that smooth.

You're going to want to thoroughly scrape off the paint. If that leaves things a bit rough, that's good for the bonding.