What is Varnish: What Does it Do?

Simply put, it’s a liquid that can be applied to all kinds of materials, most commonly wood, that coats the material and protects it. It normally dries clear. The item that has been varnished will last longer and be easier to clean than it would have been without this coating.

What is Varnish: What’s it Made From?

This is a good question, especially if you’re looking at how to safely paint baby furniture or what kind of varnish is ideal for wooden floors. Varnishes can give off volatile organic compounds, or VOCs, that can be harmful to human health and the environment. A report by CBC Marketplace revealed that any VOC levels over 500 ppb could cause issues for some people, if they have chemical sensitivities. Because some varnishes and paints have so many VOCs, it’s not uncommon for studies to show that indoor air can have two to five times as much of them as outdoor air. It’s worth looking for something labelled zero VOC varnish or low VOC paint for avoiding polyurethane fumes. The safest varnishes are oil-based and made from things like plant resins, clay, and natural plant latex. Tung oil varnish and linseed oil varnish are excellent, environmentally friendly ways to coat and protect.

What is Varnish: How Do I Apply It?

If you’ve got your clear varnish and are ready to use it, first check your temperature. Between 70 and 75 degrees is ideal, and anything higher is likely to cause the solvent to evaporate too quickly and the varnish will not set correctly. If the temperatures are right, make sure the item is perfectly clean and cleared of all dust. Most varnish is applied by brush or roller, but spays can also be used. Thin a bit of the varnish with mineral spirits–half varnish and half solvent–and apply this first as a sealant. When it’s dry, dust and wipe to remove any particles and then add three or four coats of varnish, waiting for each to dry before adding the next.

What is Varnish: How Long Will It Last?

This depends upon what type of varnish you’ve used and whether the varnished item is mostly used outdoors or indoors. For the average indoor furniture piece, new varnish will be needed every two or three years. A wooden deck or other outdoor item will need re-varnishing every year or two, depending on the quality of varnish you used. The manufacturer of the varnish you use will give suggestions for how often to re-apply. This may seem like a lot of varnishing, but the whole point is that the varnish take the beating instead of the item it’s coating.

Now you know all about varnish! It’s a great way to extend the life of furniture, floors, and decks, among other things. If you have wood you need to protect, find a low VOC varnish and make sure it will look good for years to come.