Tongue and Groove Wood Siding: Installation Tips

Tongue and groove wood siding is one of the most popular for exterior walls in homes. Wood boards are interlocked along a surface such as a wall, floor or ceiling. The long edges of boards are designed to have a rib and groove. The rib of one board fits into the groove of an adjacent board. This creates a solid wooden surface. Siding can be installed vertically or horizontally. It makes an attractive and durable exterior surface when properly installed. Below are some tips that will come in handy as you install the siding.

Board Selection

Be sure to select your boards carefully. The siding consists of individual boards which are bound to have variations in color and appearance. Careful selection will enable you to create as much of a uniform appearance as possible once installation is completed.


It is best to apply a finish on all 4 sides of the boards before you install on the wall. This ensures that the cut edges receive an adequate cover of finish. It is harder to achieve this when the individual boards have been nailed into place. The finish provides extra protection to the wood and also facilitates proper adhesion. Be sure to select a primer or pre-finish that is compatible with the final coat.

Horizontal Application

For horizontal application, begin at the bottom and work your way up. The grooved edges should face downwards. It is best to begin at one corner and work your way upwards.

Vertical Application

The grooved edge of the board should face the adjacent wall and the first board must be installed plumb. A level or plumb line comes in handy to ensure a plumb fit. You may have to trim the grooved edge to achieve a flush fit. Nail the boards to the furring strips underneath.


In both applications, you need to drive in the nails 1 1/4 inches into the furring strips. Boards that are up to 6 inches wide can have the nail heads flush with the surface while wider boards can have the nail heads exposed. It is best to use rust-resistant nails. Be careful as you drive the nails into the boards since it is done along the edges. If not installed well, the nails can damage the wood.

Cutting the Boards

Place the boards on a stable and level surface such as a work table. Ensure that the boards face downwards before you cut. It is best to use a saber or circular saw. This will prevent splinters on the wood veneer.

Fitting Boards around Doors and Windows

Remove all trim around the openings. Measure the distance available between the edge of the last board and the door or window edge. Transfer the measurements to the board and cut as outlined in the previous section. Be sure to space the boards exactly the same on both sides of the door or window. If you space differently on both sides, one side will end up taller than the other. This creates problems with alignment above the opening.