“Okay, here’s a situation. 2nd floor living room. Existing flooring is a 2′ square ¼” thick plywood tile. The subfloor is a little strange. It is ¾ T&G, then ¾” centimeters, then the ¼” thick plywood tiles. Here’s my simple question: can I lay down ¾” hardwood on top of the plywood tiles? Existing floor is in okay shape, no loose or creaking tiles, just visually scratched and beat up.”

A compelling reason to check for flatness before starting: At this old home, the exterior walls had settled, creating this drastic slope in the wood floor.

You can’t make this up. But if you’ve done enough remodeling jobs, you can probably relate; in fact, you can probably offer a few (or more) wacky examples of your own.

You might have even fallen prey to some of the other common traps that lie in wait when tackling a wood flooring job in a remodeling project. Have you ever said some of these things, or heard other contractors say them? “The existing wood floor is OK, so I’m sure this one will be fine.” “We don’t have to test for moisture, because we’re putting in an engineered floor.” “It’s an old slab, so it’s dry by now.”

Below are a few of the most common traps wood flooring contractors walk into on a typical remodeling job. Make sure you don’t fall victim by making these mistakes on your next remodeling job.

1) Mishandling Existing Floor Coverings

When you begin a remodeling job, you never know what awaits as you peel back the layers. And what you discover can land you in big trouble if you aren’t mindful of the proper way to handle those products.

By now, everyone should be well aware of the legalities and health risks involving lead. If you work on a home built before 1978 and disturb more than 6 square feet of “lead-painted” areas, you must be certified to work using lead-safe practices. Although many wood flooring contractors still seem to think this means only paint, the law defines “paint” as “paint or surface coating”—that includes any wood floor finishes and stains, so wood flooring and baseboards are included. If you get caught doing such work without certification, you can be subject to five-digit fines. (See the article “Get the Lead Out” in the August/September 2014 issue of HF for details on this law and how to comply.)

Another health hazard that may lurk on a remodeling job is asbestos. This known carcinogen may be present in old resilient floor coverings, including some vinyl composition tile, vinyl tile and sheet, linoleum tile and sheet, and rubber tile and sheet, as well as their adhesives. If you suspect a product may contain asbestos, don’t disturb it, which exposes you to liability. The best option, when possible, is to leave it in place and install over it, since it is a risk only when it becomes airborne. If that isn’t an option, ask the homeowners to hire a certified testing firm to test for asbestos. If it tests positive, a professional trained in asbestos remediation will have to remove it.

Speaking of professional remediation, mold is another discovery that is best handled by professionals. While it may present a health hazard, for the wood flooring installer, its presence should be particularly concerning since it indicates a serious moisture problem that must be addressed before any wood flooring work should be considered. In all cases, it’s critical for the wood flooring professional to seek out certified testing/remediation companies to take care of the concern before beginning work.

2) Not Using the Appropriate Subfloor

Photo Credit: Roy Reichow | Professional Flooring Consultant

Subfloor prep can be particularly challenging on remodeling jobs. Above: A high spot that turned into squeaky floor when wood flooring was installed over it.

The usual mantra for wood flooring professionals is to make sure your subfloor is clean, flat and dry. On a remodel, those rules still apply, of course, but before you even get there, you must figure out: What lurks underneath that existing floor covering? One contractor tells of a remodeling job where the crew discovered six different types of subfloors just in the area where they needed to install their hardwood flooring. It was a beast of a job, but the contractor had the expertise to make the subflooring consistent and choose a wood floor that would work throughout the entire installation.

How do you even know what your subfloors are on a remodel job? Sure, you can peel back some carpeting in a closet or remove a vent to take a look. But is that particleboard really there throughout the entire area? Are there rooms where they already added onto the house, and the subfloors there are different? Part of the home could have old board subflooring, part could be over a slab … or something else. Now what?

Photo Credit: Roy Reichow | Professional Flooring Consultant

High spots should be marked and addressed so they are within the tolerances of the NWFA Installation Guidelines before wood flooring installation can begin.

Experts emphasize that you need to use the same subfloor over the entire job so that the flooring will perform consistently. Just like you should never mix staples and cleats on a job, you should use the same subflooring. This can mean extensive preparation. You should never add a cementitious subfloor over a plywood floor, so having a consistent subfloor throughout a job may mean adding plywood subflooring over a slab—but what if there isn’t room? You might be faced with the customer not being able to install the flooring they want due to height issues with cabinets or doorways.

The potential problems with subfloors are too numerous to list them all, but, in addition to the usual “clean, dry and flat” mantra, here is a checklist of some common concerns on remodeling jobs:

 Are there areas of the subflooring that have water damage, pet stains or other damage? Are the joists under that damage still structurally sound?

 If you add subflooring and new flooring, will it lock in kitchen appliances?

 Are the plywood or other wood subfloors so old and brittle they don’t have enough holding capacity left for fasteners?

 Is the slab lightweight concrete and therefore not appropriate for a direct glue-down job?

 Is the floor uneven? It may be flat, but does it have a noticeable slope like the flooring on the first page of this article? Will the customer be OK with the slope? Old homes often settle, especially in exterior walls, so this is a common issue.

As the wood flooring contractor, protect yourself by ensuring there is a clause in the contract excluding major subfloor preparation and making it clear that subfloor work must be assessed after the subflooring is actually exposed.

3) Assuming Environmental Conditions Are OK

Photo Credit: Roy Reichow | Professional Flooring Consultant

Not an uncommon scenario on a remodeling job: This is what happened when the roof was torn off the house before the wood flooring was supposed to be laid. Simply replacing the plywood is the fastest option.

There seems to be a common misconception when remodeling that you don’t have to worry about the moisture content of the subfloor or the RH in the home. After all, the home and its subfloor have been there for a while, possibly decades or even longer. But just because the home and its existing flooring have long ago reached equilibrium doesn’t mean new flooring will happily adapt. Slabs continue to soak up and release moisture like a sponge. Conditions in basements and crawlspaces change. Remodeling often involves adding substantial moisture to the home with new concrete, new tile, new drywall, new paint and more. Sometimes remodeling can even involve a change in the HVAC, such as going from old radiators to radiant heat. Approach every remodel with the same caution as you would that new home with the 30-day-old slab or the freshly poured basement.

In particular, contractors seem to make the mistake of …

4) Thinking Engineered Flooring is Impervious to Any Conditions

On many remodeling jobs, engineered products are the go-to option, and with good reason—they’re more stable than their solid counterparts, making them a good fit for a variety of job sites. They’re usually prefinished, meaning they offer an appealing turnaround time, with no potential smells during finish curing. These days there are engineered products in every size, shape, species, color and finish option you can imagine, and there are many high-quality options on the market.