Self-leveling concrete not adhering to wood floor

2/28/2021 at 9:25:41 AM

Hello,

This comes down to prep work. Make sure the floor was swept clean and then clean the floor with a moist mop to remove all remaining dust. Apply a select primer (manufacturers recommendation) to the plywood before the self leveller (this will help it adhere to the wood).

2/28/2021 at 9:37:08 AM

Good day,

1st thing u should do is take up any loose cement.

2. Skia recommends using Sika 01 primer 1st. This will promote adhesion.

Remember the Sika 125 self leveler should not be poured any thicked than 1.5" in 1 pour.

Make sure your floor is really clean also.

Remember this is a lot of weight your adding to the floor. If you have joists make sure they can handel the extra 1200lbs

I hope this helps, good luck.

Michel Auger

Hammer Away Construction & Remodeling

2/28/2021 at 10:07:24 AM

Thanks a lot for the replies, the primer seems to be the missing piece. I am hesitant on on what to do in places where it makes noises, I don't particularly want to remove it all so maybe a second pour will remove it.

As for weight I believe it will be ok, that floor used to support the roof and that is why it caved so much. We reinforced the middle with a steel beam, but curious to know what are the recommendations for that.

2/28/2021 at 11:03:12 AM

Good morning

Clean the floor very well.

You can purchase a primer to get the concrete to adhere.

2/28/2021 at 12:59:27 PM

Emile, You have received some good advice. Prep work is the key to any job, especially floors. Make sure everything is as clean as possible abd use the recommended primer. If you use a different manufacturer than has been recommended, the adhesion may not work as well. As to the cracking, it sounds as though there may be some movement between the joists and the sub-floor. check underneath and use shims & glue where you notice some movement. Good luck.

2/28/2021 at 11:14:48 PM

I would have to guess if it flaking off and the floor is out by 2 inches in places, the structure is not sound. From what I see there is too much flexing going on. What size joists are under the floor, and at what spacing are they?

Or perhaps the sub floor or underlay isn't attached properly?

3/1/2021 at 9:37:49 AM

Good afternoon,

I would definitely remove the first coat that hasn't adhered, adding more on top will make for a bigger mess down the road especially if you have 2"s to go?!

I would recommend removing the ply to the floor joists, add 2x4 shims on top of the joist(if there is a steel beam added in place, I'm surprised they didn't level it accordingly while placing it)) to the exact level required. A laser level will make this job very simple!

Place a 2x4 on the floor joist, turn on your laser level, mark where laser hits, cut accordingly. ensure to also take away ply wood thickness.

Picture attached is a quick representation of what your going for. they are putting a slope on a flat roof, your removing a slope from a the floor!

Hope that helps!