I had the same problem. Had old strip flooring that was over 100 yrs old. At one point someone replaced a section with 3/4 thick wood floor but you wouldnt know until it was tore up. When I laid all the flooring an got to the the hallway I was up about 1/2 in. I shimmed up an 1/8 in then stripped a blank of the new floor on the table saw to build a thin transition piece. There is a slight raise but everything is the same level and looks nice. So in short just use a reducer.

I know this is rather late, but .... We had Mullican 3/4" brazilian cherry - solid with aluminum oxide finish - installed in our new home. We had the same wood (from the same company) installed 10 years ago in our old home. The old floor is perfect. The new one is uneven. The boards vary in height and width to the point several people have tripped due to their foot catching on the uneven surface. It has been some time now, and there still is no solution offered. My most recent response was "the manager is on vacation". Just to emphasize, it is gorgeous, and the old floor is perfect. Hope they will fix the new one!

It's splintering and cracking because it's maple - hard, durable and brittle. And prying boards up is guaranteed to destroy them. You have to remove them by reversing the motion it took to install them. The screws look like the easy way out, and the least expensive, if you haven't reached the point of no return on the removal. If you want to salvage the wood - and it's selling for $5+ per square foot as salvage - buy an oscillating multi-tool and several metal-cutting blades. Slice through the nails under the boards and coax the board loose. If you can work from the side with the tongues, the nails are accessible and the boards easiest to remove. It's faster, and easier and saves more boards. Remove the molding and use a wood-cutting blade on the multi-tool to slice out around the cabinets, but accept that it's going to be difficult to impossible to do a clean job, and the new floor will abruptly end at the cabinets. If appearance matters a lot, remove the cabinets, take up all the floor, put down the new floor and re-install the cabinets.

Wood vs. Engineered Wood? No contest in this case. If the home was built in 1905, put real hardwood in. This preserves the integrity of the home's building materials. Plus, as you can see from the age of these floors, higher grades (i.e. thicker) hardwood can be sanded several times; you usually don't get even one chance to sand engineered wood. The hardwood layer at the top of this multilayered product is simply too thin. Level Floors and Subfloors There are ways to level a subfloor, ranging from replacing parts of the subfloor with thicker or thinner sheets of plywood (or planks, see below), to pour-on leveling compounds that harden to make the entire floor level. What you use to level uneven areas depends on what the subflooring is. If it is plywood or concrete, the compound works. But more likely with this home, on floors at or above grade, there will be wood planks laid at a diagonal across the floor joists. So in your home, the layers were probably joists first, then subfloor planks of wood, then hardwood with tongue & groove joints. You cannot effectively use a pour-on leveling compound on a plank subfloor, as there are cracks between the planks. However, you can lay a new hardwood floor directly on a wood plank subfloor as long as those planks are sound and relatively level. Replace individual planks that have been damaged by water or insects, are otherwise compromised, or even missing (it happens!), with either new planks of lumber, or with plywood of the same thickness as the planks. Any lumber you install, for either the subfloor or finished flooring, should be brought in to your home several days prior to installation, so the materials acclimatize to your typical interior temperature and humidity. Unlike for ceramic or porcelain tile, the subfloor does not have to be perfectly level. And unlike vinyl sheeting, planks or tiles, the hardwood won't "telegraph" minor differences in height, and minor surface irregularities, so the subfloor doesn't have to be absolutely perfect; it should be sound, strong, uniform and essentially level. Your flooring contractor can give you specifics on what upgrades your subfloor may need once the original hardwood is removed. Joists If the floor is significantly not level in parts, or if certain areas feel spongy when you walk on them, I recommend you have your flooring contractor, a home inspector, or structural engineer inspect the subflooring and especially the floor joists. You don't want to invest in a new floor, only to have it become damaged because some joists weren't attended to. Transitions Transitions (a.k.a. thresholds or molding) between existing rooms and the new floor ought to be made of the same wood and same finish (stain, polyurethane, etc.) as the new flooring you are putting down. As wood ages, the finish becomes darker, so trying to make the transitions match the finishes of existing floors is very difficult and not recommended (what will match those floors right now won't match later after your transitions age up a bit). Eventually, the transitions wouldn't match either the new or the old floors! Transitions come in four types: reducer (when the two floors being joined are of different heights), seam binder (when the floors are the same height, and the boards from each are very close to one another), T-mold (when the two floors are the same height, but there is a crack between the two rooms' flooring) and stair nose or stair edger (when the flooring needs to curve around the front of a stair's "tread"--the flat part of a stair upon which you tread!). The transitions for your particular project can be ordered when you order the hardwood, so make sure to include measurements for those doorways/entrances. The contractor can tell you if he/she anticipates there will be a height difference or gap between the floorings, which would require those particular transitions. Dry Air Concerns Consult a local lumber supplier or flooring contractor familiar with your local climate conditions to discuss finishes or other tips for keeping your wood floors healthy in the dry winters. Sounds wonderful! Have fun!