How to Flatten a Tricky Subfloor?

[_Jag_]

Hey all, new to the forum.
I have some flooring I need to install and need some help.
The project is in a second story condo, the subfloor is a gypcrete like product. The flooring being installed in Riva Metro engineered hardwood, 6 3/4” x 96” and will be glued down. The flooring direction will be running off the door wall into the center of the room, 7’ and transition into carpet. The floor has quite a slope over 7’, as well as a low spot in the center. I found the lowest point and measured the height gain from there (see the photo for measurements). I'm not sure how to go about flattening this floor before installing the flooring. Any help would be greatly appreciated!

 

[Incognito]

Easiest for a DIY would a gypsum compatible self-leveling pour.

Schönox AP - HPS North America, Inc.

I would pull the carpet back a foot or two off the transition and pour a couple bags at a time------most likely one pour of two bags-----that ought to be sufficient. Follow the directions carefully with regard to priming the gypcrete substrate and mixing your self-leveling.

It's MUCH better to mix two bags at a clip and make one pour as opposed to two mixes and two pours so the whole puddle lays out and flattens itself correctly. Watch half a dozen YouTube videos. Rent a strong, slow speed drill motor. You'll have to buy the paddle and large mixing pail. EVERYTHING you read in the instructions is pretty darn critical so forget about improvising and just do what the bag says!

You might enjoy this video I just reviewed. She actually LEVELS this plywood subfloor. You only need FLAT but other than all the laser work you've already done the procedures for self-leveling I found both informative and quite pleasing to the eyes. :

 

[highup]

I agree with incognito. Use a self leveling product compatible with a gypsum product like you have.
Be sure to use the primer made by the manufacturer of you choice.
Like he said, follow the instructions.
If It says add six quarts per bag, don't add six quarts plus another cup because you think it looks to thick.
It's science and chemistry. Be as exact as you can.

 

[C.J.]

I watched that video a couple times. Prolly watch it a third time just to make sure I didn’t miss anything

 

[Incognito]

I watched that video a couple times. Prolly watch it a third time just to make sure I didn’t miss anything

Right?