I've finally gotten to the point that I'll be installing 3/4" hardwoods in several rooms of my house. While removing the carpet and inspecting the subfloors I found that there is an underlay of OSB (approx less than 1/4") under the linoleum in the kitchen (between the kitchen and carpeted room), so there is a considerable difference in height from one room to the other. I tried removing a small piece of the underlay...it has appaprently been glued (very well) on the section I tested and isn't coming up very easily. I'm not sure what to do now. I would really like the transition between rooms to be continuous. Should I attempt to continue removing the OSB? Does it get easier once you get toward the middle? Or perhaps I should just sand and settle for a slight incline in the transition (which I don't really want to do)? Is there an easy way to remove the OSB and linoleum? Any suggestions would be greatly appreciated. Thanks very much!
Unfortunately, there's no "easy" way to remove glued vinyl and flooring. If you want the floor levels to be flush and even from one room to another, now is the time to cut out the kitchen flooring level above the subflooring.
Use a circular saw with an old blade (you WILL hit nails or screws) adjusted to the depth of the flooring above the subfloor, and safety glasses. Cut it out in no more than 2' squares or so for easier removal, and pry the sections to be removed up with a flatbar, crowbar, clawhammer, etc. to remove it.
Depending upon when and how your home was built, you may have 3/4" subflooring + 5/8" flooring + the 1/4" OSB (probably used for leveling) and the vinyl.
You'll have to cut into it to see what you actually have, then remove what is necessary to get the floors to come out level from room to room
A word of caution about installing hardwood, tile, etc. in a kitchen. If you decide to raise the level of the kitchen flooring, you may trap the dishwasher in the cabinet base. Raise the cabinet base and dishwasher to the new floor level with plywood and shims. (I always use pressure-treated plywood anywhere there's going to eventually be a water leak, but that's your call.)