There are several methods of removing varnish from wood surfaces. Which one you choose will depend on the item and the environment in which you are working. For large bulky items, such as doors, consider taking them to a specialist finish remover where the item can be dipped into a chemical solution. However, this treatment is harsh, often dissolving glue and loosening joints, so you may want to undertake the work yourself, especially if the object is valuable or delicate.
Non-chemical varnish and paint removers
Large areas of varnished wood are best tackled with a heat gun and scraper. Heat guns are readily available at DIY outlets or online stores. Two recommended models are the Bosch PHG 600-3 1800 Watt Hot Air Gun, and the budget priced Einhell Hot Air Gun. Heat guns are useful for stripping doors, painted panelling and window frames – fit a guard to the heat gun to prevent adjacent glass cracking.
Delicate pieces of furniture should be treated carefully by rubbing with steel wool and denatured alcohol. This may be all you need to remove thin coats of shellac. If the surface is a little resistant, try a mix of four parts white spirit to one part linseed oil.
You can also remove varnish by sanding, but it can damage the surface and may also force varnish back into the wood grain. However, a heavy-duty electric sander is the only efficient way to tackle a wood floor.
Chemical strippers vary widely in effectiveness. All require a thick application to the wood surface and then a period of time for a reaction between the product and varnish to take place. Nitromors is the most well-known brand. It is fairly fast-acting – the length of time it requires to work depends on the layers of varnish (or paint) that need to be removed. Follow the manufacturer's directions carefully; this substance gives off noxious fumes and should only be used in a well-ventilated area.
Another brand that works very well is Peelaway. This is applied to the wood and then covered with a paper “blanket” and left for 24 hours. Remove the paper, and the stripper and varnish lifts away with it for easy disposal. The manufacturers claim that Peelaway can remove up to 32 layers of paint and varnish with one application.
Eco-friendly varnish removers
There are a number of eco-friendly varnish and paint removers on the market. One of the most readily available ones is Home Strip. It works in the same way as a regular chemical stripper – apply to the wood, leave for 30 minutes and scrape away. Use wire wool to remove any residue. If there are children or animals in the home, Home Strip is a safe option as there are no harmful fumes or solvents.
Varnish removing tools
Whichever method of varnish remover you use, you will need paint brushes (use old or cheap ones to apply chemical strippers), a stripping knife, scrapers of various shapes, steel wool in coarse, medium and fine grades, and white spirit and clean rags to remove any remaining debris. Some products may advise you to wipe the wood down with a damp cloth but be careful of using water on a delicate piece of furniture as it will soak into the open grain. You will also need to protect the area with drop sheets. If you are working outside, sheets of cardboard will prevent chemicals discolouring the ground.
Safety precautions when stripping varnish
Always use a protective face mask and safety goggles when undertaking any paint or varnish removal. Wear heavy-duty rubber gloves when using chemical strippers – have a spare pair available as it is easy to snag gloves on small nails or splinters. Make sure the area you are working in is well-ventilated.
Dispose of old varnish and stripper carefully; always refer to the manufacturer's directions as varnish is flammable. Never put chemical remover and scrapings into domestic waste as they could start a fire. Wrap carefully and take to your local waste disposal centre where they can be disposed of safely.