Here are some resilient flooring questions and answers.

Can I install a new floor covering over old adhesive residue?
When installing new Vinyl Composition Tile such as EXCELON® and Standard EXCELON®, Armstrong allows the use of S-89, S-515, S-700 and S-750 Resilient Tile Adhesives over old adhesive residue as long as the adhesive residue has no ridges or puddles evident and what remains is a thin, smooth film. For felt-backed flooring over cutback adhesive, 80% of the overall substrate must be exposed, 100% exposure for vinyl-backed flooring. Prior to removing any cutback adhesive, test for asbestos in the adhesive. The other option is to apply a layer of patching compound over the old cutback. When patching over cutback, follow the patching manufacturer’s recommendation for degree of adhesive removal and patch application thickness.

Should I use an adhesive remover to remove adhesive residue from a subfloor before installing a new floor?
Many adhesive removal products contain solvents that leave a residue within the subfloor. This residue can negatively affect the new adhesive and bleed through the new floor covering. Floor covering warranties do not cover instances where existing subfloor conditions cause damage to the flooring or installation failure.

Can I install a resilient floor on a radiant-heated substrate?
Armstrong flooring may be installed over radiant-heated subfloors as long as the surface temperature does not exceed 85°F. Temperatures above 85°F will cause the flooring to soften and increase the risk of irreversible indentation.

Why do flooring manufacturers recommend not smoothing true expansion joints with any type of patching product?
True expansion joints are those placed between separate pours of concrete. These joints are designed to absorb the movement of the concrete and are normally filled with elastomeric fillers which absorb the movement of the separate pieces of concrete. If an underlayment is placed across or in these joints, the movement of the concrete will cause them to break up or will push them out of the joint. Additionally, any flooring placed across these joints will break with the movement of the concrete. Expansion joint covers, which are designed to span these joints, should be used in these areas.

Why can’t you install flooring directly over paint or other coatings on a subfloor?
The bond of the flooring to the subfloor is only as good as what you bond to. If you bond to old paint, sealers, polish, or other foreign matter, you are dependent upon the bond of that material to the subfloor to hold the flooring in place. Since we cannot determine how strong that bond may be, it is best to bond directly to the substrate. Epoxy based paints are also very difficult to adhere to.

If you have a subfloor such as particleboard or hardboard, which are underlayments not recommended for felt-backed sheet flooring, do you need to replace that underlayment?
Particleboard and hardboard are not recommended for fully bonded floors due to dimensional instability. They expand and contract at unpredictable levels and can cause a fully adhered floor to push up at the joints of the boards. These subfloors should be covered with a ½” thick underlayment prior to installing a felt-back or cushioned type flooring

What is a sleeper-constructed subfloor and why can’t I install flooring over this?
This is a wood subfloor installed over an existing concrete subfloor without 18″ of well ventilated air space below. Concrete on or below grade will have some moisture in it due to its proximity to the ground. When there is not enough ventilation, moisture will build up causing not only installation failure, but possible rotting of the wood. Suspended grade subfloors that are not sufficiently dry can experience the same problems.

Why should new tile not be installed over existing tile that is below grade?
Tile over tile is not recommended on a floor below grade. A basement is below grade and concrete below grade will almost always have moisture in it. A single layer of tile allows any moisture in the concrete to escape through tile joints. When you place new tile over existing tile, you cover the tile joints and cut off the escape route for the moisture. This traps the moisture beneath the tile and can cause loosening of the old tile as well as the new tile.

What board underlayment products should I put in place before installing resilient floor products?
Underlayments for resilient floors should be structurally sound and designed for resilient flooring underlayment purposes, with a nominal thickness of 1/4″. The panels should be smooth enough so that the texture or graining will not show through the finished flooring. They should also resist dents and punctures from concentrated loads. The panels should not contain any substance that may stain vinyl such as edge patching compounds, marking inks, paints, solvents, adhesives, asphalt, dye, etc. Check with your supplier or panel manufacturer. Install the underlayment in strict accordance with the board manufacturer’s recommendations. JJ Haines carries the Ultraply XL Underlayment board.

Can resilient flooring be installed directly over strip wood, board or plank-type subflooring?
These subfloors must meet structural requirements. Regardless of whether the subfloor is single- or double-layer, the following is recommended: If the top layer is tongue-and-groove and the strip wood is 3″ or less in face width, cover with a nominal 1/4″ or thicker underlayment panels. All others should be covered with 1/2″ or thicker underlayment panels.

What can be done to prevent a cracking sound when installing underlayment boards over a tacky residue?
Place a layer of felt or polyethylene sheeting over the residue before installing the underlayment boards.

There are two vinyl floors already down, is there any option other than removal?
If over wood, a new wood underlayment may be installed over the vinyl floors and then the new vinyl. If over concrete, the vinyl floor must be removed. Severe indentation in the flooring increases when you install over 2 or more layers of flooring. In commercial work in areas with rolling loads, I strongly recommend removing any existing flooring and installing over new underlayment or directly over the concrete due to indentation and the smooth face of commercial flooring structures.

Can I glue down a resilient floor directly to the Oriented Strand Board (OSB) subfloor?
No. When gluing down directly to a subfloor such as OSB, you must first apply a nominal 1/4″ or thicker underlayment panels. OSB is made up of different wood chips and there are different grades (smoothness) of OSB. Gluing directly over OSB, these chips swell at different rates and can telegraph through the vinyl flooring. Also, at the tongue and groove of the OSB, you will get buckling as the subfloor goes through seasonal change. The OSB brand called Advantech, I recommend applying a nominal 1/4″ or thicker underlayment panel when adhering any type of flooring over it. Advantech has a highly moisture resistant resin which can be difficult to adhere any type of adhesive to.