Similar to common laminate cabinets, thermofoil cabinets are constructed with a plastic vinyl layer laminated to an MDF (medium-density fiberboard) core. Both standard laminate and thermofoil cabinets can effectively mimic the look of wood cabinets but generally cost considerably less. This economy comes with its disadvantages, however, since any laminated wood product runs the risk of delamination, and the very thin layer of PVC material used in the thermofoil process is especially prone to peeling.
Wood Veneer vs. Plastic Laminate vs. Thermofoil
Whenever you have a laminated or veneered material, you run the risk of delamination. For example, it is not uncommon for furniture made of hardwood veneer laminated to a solid wood core to begin peeling after a few years. Traffic, use, and water contact or humidity will only speed up the process. The same holds true of plastic laminate furniture, where the layers of plastic bonded to the MDF core can also delaminate and separate.
But thermofoil cabinets are especially prone to delamination. Thermofoil is a thin PVC vinyl material that is applied to MDF under both vacuum pressure and heat. While the bond between the thermofoil and MDF has short-term integrity, over the longer term, this bond can fail. Thermofoil is a considerably thinner (and cheaper) material than either wood veneer or laminate veneer and thus is much more susceptible to peeling.
Heat, moisture, or a combination of the two often are enough to loosen the bond between the thin thermofoil layer and the MDF core. Woodworkers and cabinet installers report the same pattern: thermofoil delamination commonly occurs on cabinet surfaces located above coffee makers, toasters, toaster ovens, and convection ovens. In bathrooms, the equivalents are curling irons and blow dryers. Because bathrooms are high-moisture environments, humidity and direct contact with water will only exacerbate the delamination process.
Repair vs. Replacement
While delamination of wood veneer or standard laminate cabinets is generally easy enough to repair, the decision becomes a little harder with thermofoil cabinets, especially if the peeling is widespread.
If your thermofoil cabinets are showing localized damage that is focused on only one or two cabinets, or in locations subject to constant heat and moisture, then you may want to proceed with the repair. Regluing the thermofoil layer is not difficult to do using contact cement and clamps. But if this is a kitchen-wide problem, you should consider replacing your cabinets entirely or installing new door and drawer front panels. Unless you have a pressing financial reason to choose repair for the entire kitchen, you may want to save yourself the aggravation and start fresh with new cabinets. If the cabinet boxes are in good shape but cabinet doors are peeling, your best bet is to purchase new cabinet doors.
If the MDF itself is bulging or is in any condition other than completely flat and smooth, there is really no point in trying to repair the cabinets. Warped MDF cannot be sanded down, planed, or otherwise smoothed.
With only a few simple tools and materials, you can repair thermofoil. As long as the MDF core is in good condition, it provides an acceptable surface for regluing the thermofoil layer.
Source: The Spruce
