Tongue and groove, which is often abbreviated to T&G, is the installation method of a particular type of wooden flooring. It is classed as the traditional way to fit flooring and has been used for decades to install both solid hardwood and engineered hardwood flooring.
As the name suggests, the planks of tongue and groove flooring have tongues and grooves that fit together. Each plank of T&G flooring will have one long and one short side with a tongue (a protruding edge), and one long and one short side with a groove (a rebated edge). These tongues and grooves are precisely machined on to the planks of flooring during the manufacturing process to create a tight and smooth fit once fixed together. Tongue and groove flooring can be installed in a number of different ways, including: secret nailed, secret screwed, glued directly to the subfloor, or floated over an underlay with the edges glued together. It is available in both solid hardwood and engineered hardwood formats, meaning that it can be installed over any subfloor of sound quality that has been properly prepared.
One disadvantage to tongue and groove flooring is that it can be quite difficult to install and often requires the work of a professional wooden floor fitter to ensure it is fitted correctly. The alternative to tongue and groove flooring is hardwood flooring with a click fitting system.