Leveling Old Basement Floor

[42qn30]

I have decided that I'm moving my office to the basement. The home is about 100 years old with a very uneven floor. It varies in depth suddenly all over with a total variation of possibly 2". The floor has pits and concrete repairs all over it. The previous owners put down Drylok Masonry Waterproofer. I have spent half the day researching coatings and am still a bit lost.

I believe the best course of action is to use a self leveling concrete and throw some thin carpeting over the top of SLC. All of the research shows that the SLCs do not like to bond to the Dryloc and it must be fully removed prior to application. Removing it completely will be extremely difficult due to the rough surface. The Dryloc is a latex based product and it looks to me that a lot of the self leveling concrete seems to be latex based as well. Can I just scuff the surface to hopefully give it enough surface energy that it will bond to it? Can I be really lazy and just pour SLC on top of the painted surface since it will be a light duty area with only foot traffic?

Are there any other products anyone can recommend as another course of action? Thanks in advance.

 

[theoldwizard1]

A lot more work and money, but it will result in a much nicer, more COMFORTABLE floor is to place elevated, insulated floor panels like Dricore or Amdry down and level them.

You will have a nice, level, dry and warmer floor than any cementitious product.

 

[b-boy]

I recently did the same thing to my basement.

My house is 130+ yrs old. The basement was very dry. The concrete was in decent shape, but the entire basement sloped badly. There was about 3.5+ inches slope from one side to the other.

I looked into self leveling compound. I even contemplated re-pouring the floor. It was going to be very expensive to do either.

I ended up building a raised floor using pressure treated 'sleepers' with 3/4" exterior grade plywood on top of that. The final floor was pergo laminate.

I started with a 6 mil vapor barrier, then sleepers with 1" XPS between the sleepers, then the subfloor. The sleepers are screwed into the concrete floor. I was able to level the subfloor as I built it using an 8 ft level. I used wood block, shims and subfloor adhesive to level the floor. It is rock solid.

 

[Armorpoxy]

Hi
We are a master distributor for Laticrete self levelers. They offer for their Drytek Levelex commercial resurfacer an acrcylic bonding primer which should adhere fine to Drylok we are told by the factory, but best you confirm that with them since the surface is not bare concrete.

One of the ways to keep costs down with self levelers is to put down inexpensive pea gravel to take up the space and level over that.

https://armorpoxy.com/products/laticrete-drtek-levelex-primer-1-5-gallon/

https://armorpoxy.com/products/laticrete-drytek-levelex-self-leveling-resurfacer-50-lb-bag/

 

[rburke65]

Armorpoxy.....I wouldn't have thought about using small sized gravel to level first. Great idea.

 

[Armorpoxy]

No worries, that's why we're here.

We actually have a lot of experience with this since we own own one of the NYC area's largest concrete surface prep company www.prep-crete.com, running about 50 workers daily doing grinding, shot blasting, polishing, coating installation, self-levelers, etc. so we have a lot of real 'hands on' experience with things working in very logistically challenging situations.

We often get tasked with having to re-level old floors so we use lasers to mark the height, and if over about 1" needed to level we use pea gravel to fill in and then self-level over the pea gravel. We just did a 22,000 sq ft floor on the 45th story that was 6.5" out of alignment!

 

[mobiledynamics]

You're going to need to grind and sweep/rinse/clean before anything will bond.

 

[42qn30]

I decided to go with what b-boy recommended. So far so good. The perimeter was leveled first with cedar shims. When everything was level I used powder actuated 3" nails to shoot them into the board, shims, and concrete. The concrete they used isn't that great and about 15% of the anchors are a little loose. Overall everything feels solid. This is time consuming but pretty straight forward. Thanks to everyone for the ideas.