Treatments applied to the furniture or wooden countertop supporting the sink to resist humidity

The idea of using wood for bathroom furniture almost always comes up against the fear that it will not withstand the wet environment. This fear is unwarranted when you think of the wooden barrels used for bathing in the past, the Finnish saunas or the wooden barbecues you used to find in most bathrooms. Wood does well in these environments, and if protected, mould growth will be avoided. An oil-treated bathroom countertop holds up very well, provided that finish is refreshed when the oil wears off. Much more sensitive to water are glues that must be made with resistant adhesives and the materials or construction solutions used to make bathroom furniture. Let's see how we can finish a wooden countertop or furniture on which the bathroom sink rests to make them as moisture resistant as possible.

Protection with oils

Oil is the one that best highlights the wood and preserves its natural appearance. Those who appreciate it want to see and feel it even in more difficult conditions, such as in the bathroom. A bathroom worktop can be made from any wood, but the harder species (oak, ulm, acacia) or with resin content (spruce, pine, larch). It is best to use solid wood panel. If solid wood is used, it must be jointed in such a way as to avoid water stagnation. Always use moisture-resistant glue made of Classes D3 or D4. If wooden furniture is used instead of countertops, the design should be chosen so that there are no hard-to-reach areas. Water can easily get in there, but will be difficult to wipe off. The area will remain permanently damp and develop mould. Joints with glue or metal elements must also be moisture resistant.

If you choose oil to protect bathroom countertops or furniture, look for wood oil. There are several kinds of oil. You can use tung oil, linseed oil or blends of these oils - Danish oil or teak oil (it's not teak, it just looks like teak). There are also blends of different companies, more or less natural. I say less natural because there are also synthetic oils. In general, it is the price that shows how natural a product is. The higher the price, the cleaner and more natural it is. Natural oils can be used without any problems to protect the things we come into contact with. For objects that come into contact with food, use mineral oil.

In order to be as moisture resistant as possible, the wood needs to absorb oil deeply. It is therefore a good idea to apply excess oil, allow it to soak in for 30-45 minutes, then wipe the wood with a soft cloth that absorbs well and leaves no lint. Wiping is mandatory because otherwise the wood becomes sticky. Apply the oil with a soft cloth or brush, on both sides, on the edges, including the cut-outs. After 24 hours, the time needed for drying, the operation is repeated. This allows 2-4 coats to be applied. The wood must be properly dried (8-12% moisture content), sanded and stripped.

Protecting with moisture-resistant varnishes or paints

Those who do not trust oil or want a more durable finish that also ensures the mechanical resistance of protected surfaces can use varnishes or paints. They need to be moisture resistant because otherwise they bleach and flake. This is the case with nitrocellulose varnish, which is widely known and used. It is a nice-looking varnish, but very poorly resistant to moisture. It is not recommended for table tops either, let alone bathroom counter tops.

The most resistant varnishes in such cases are two-component varnishes, i.e. varnishes with chemical curing. This is the case polyurethane varnishes, acrylic, polyester. The chemical reaction between the two components of the varnish will result in a film with very good mechanical and physical-chemical resistance. The finished countertop or furniture will be much more resistant to moisture, scratches, abrasions and knocks. In this case too, the application must be made on both sides, on edges and in cut-outs. Apply 2-3 coats of varnish (or 1-2 primer + 1 varnish), with sanding between coats to obtain a surface as pleasant to the touch as possible.

If you are planning to protect the wood in your bathroom yourself, I recommend using water-based varnishes to avoid inconvenience caused by solvent evaporation. Even if they are not hardened they are strong enough to protect the wood from moisture. There is a possibility that the varnished surface may take on an opalescent appearance if it comes into contact with water immediately after drying. Don't panic! Water-based varnish has a longer deep drying period (up to 2-3 weeks), during which time it can absorb more of the existing moisture. The opalescence will disappear if you remove the source of moisture. Recovery will be faster if there is a heat source. It is a good idea to leave the worktop on for at least 48 hours after finishing before water reaches the surface.

Rules to follow for a durable finish

To make the finish last as long as possible, thus protecting your bathroom countertop or furniture, I recommend the following:

• Coat all parts of the worktop or furniture thoroughly with oil or varnish. Don't assume that if you have fixed the sink in the cut-out area very well, there is no need to finish that area. Water easily gets into the most hidden places. And if you don't notice this it is even worse. At some point you'll smell mold and you won't know where from;
• Refinish with oil when the surface of the wood begins to change its original appearance (sometimes it takes on a slightly dry appearance). Over time, the oil is removed by wiping or during cleaning. Don't let it disappear completely, it will be more difficult to repair. If you react as soon as the appearance changes, repair will be much easier. Simply wipe the surface with a cloth soaked in oil;
• Don't leave excess oil undried because it won't dry out. It will become sticky, unpleasant to the touch and very difficult to remove;
• After using the sink, do not allow water to puddle on the oiled surface. You will shorten the time until the finish is restored.
• Sand the surface of the wood before applying the protection. Raised fibre, in addition to its unpleasant appearance, can also be the way water gets into wood;
• Use very sharp objects carefully as they can damage the varnish film. The varnishes are resistant but not impossible to penetrate. The appearance of a deep scratch compromises protection. Water can get under the film and the finish fails.

The furniture presented in the article is made by iPlan Furniture - Dragos Costache and Constantin Iosif

Photos are property of iPlan Furniture

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