How to Build a Wood Mantel
More in Fireplaces

How to Build a Wood Mantel

How to put together a classic surround from stock lumber and moldings

The humble fireplace has come a long way. Once merely a means of cooking up grub and keeping rooms warm, it's now a ceremonial focal point that symbolizes the cozy comforts of winter—and a wood mantel gives the hearth even more warmth.

Though there's no shortage of pre-made mantels on the market, we're DIYers at heart, so we set out to build one from off-the-shelf lumber.

We opted for a traditional-looking design that goes with many types of decor. Made of ¾-inch veneer plywood, our mantel is layered with elegant pilasters that are wrapped with stock moldings and baseboard, and topped with a trimmed-out shelf.

As with any fireplace project, safety is paramount. National codes require at least 6 inches of clearance all around the firebox and an additional 1 inch for every ⅛ inch a mantel protrudes from the surface; local codes might be stricter. So tailor your design or pick your product accordingly. A cardboard template can help you determine whether a mantel is the right size and scale for your space. And make sure to secure it properly to the fireplace—find complete instructions at thisold house.com/bonus. Install one soon, and you'll love how it frames your favorite gathering spot.


Steps // How to Build a Wood Mantel
1 ×

How to Build a Wood Mantel

 
Step One // How to Build a Wood Mantel

How to Build a Wood Mantel

diagram of the parts making up a wood fireplace surround shelf mantel
Illustration by Gregory Nemec

Size the mantel to fit your fireplace, and choose moldings and trim that mimic nearby profiles

 
2 ×

Cut the Pieces

 
Step Two // How to Build a Wood Mantel

Cut the Pieces

diagram showing pieces to cut to build a wood surround fireplace shelf mantel
Illustration by Gregory Nemec

Cut the shelf, breast, legs, returns, and nailing strips to size.

 
3 ×

Assemble the Mantel

 
Step Three // How to Build a Wood Mantel

Assemble the Mantel

diagram showing assembly of the mantel to build a wood surround fireplace shelf mantel
Illustration by Gregory Nemec

Attach the legs to the breast by screwing plywood cleats across their back seams. Screw nailing strips to the back of the assembly, ¾ inch from each outer edge. Set returns against the strips, flush with the outer edges. Secure them with screws.

 
4 ×

Cut and Add the Trim

 
Step Four // How to Build a Wood Mantel

Cut and Add the Trim

diagram of trim to cut and add to build a wood surround fireplace shelf mantel
Illustration by Gregory Nemec

Nail centered pilasters to each leg. Install a nailing block on each pilaster flush with its top edge. Miter and nail trim to the mantel according to the diagram below. Start with baseboard at the bottom, add crown molding at the top, then add astragal molding below the crown molding and along the bottom of the breast. Miter and nail the doorstop to the mantel's interior edges to finish the return to the surround.

 
5 ×

Attach the Shelf

 
Step Five // How to Build a Wood Mantel

Attach the Shelf

attaching the shelf to build a wood surround fireplace shelf mantel
Illustration by Gregory Nemec

Trim the shelf by mitering and nailing shoe molding to its edges. Nail through the top of the shelf into the mantel. Fill all fastener holes before sanding and finishing the entire piece.

 
 
 

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