How to Rough In the Framing for Fireplaces

Refer to your fireplace's installation guide for the exact measurements for openings and air space requirements before beginning to rough in the fireplace, since every unit is different. Design your fireplace surround with those figures in mind.

Frame a fireplace that does not reach the ceiling by building two identical sides, each about 16 inches wide and about 3 feet tall. Cut at least 6 pieces of lumber 16 inches long from the 2-by-4 studs with a circular saw. Cut 4 sections of lumber the height of your fireplace frame. Cut 2 sections of lumber the width of the front of the fireplace frame.

Butt one 16-inch section of lumber against a section of lumber the height of the fireplace frame. Check the layout for square. Screw through both pieces using two screws, with the screws going through the lumber at the join. Repeat three more times. Join two of these sections together with screws in the same fashion -- you will have two squares when you are finished. Repeat for the remaining pieces of lumber to make the top of the frame, inserting 16-inch long 2-by-4 supports every 2 feet if your top will be more than 3 feet long.

Stand the two 16-inch wide sections upright so that the 16-inch dimension is against the floor. Have a friend hold one wall section while you position the top of the frame over the two upright pieces like a cap. Attach the top to the side pieces by screwing through the underside of the lumber of the top of the wall section where the top section and the wall sections meet. Set this main section aside while you build the front of the fireplace framing.

Cut the basic shape of the frame of the front section to fit within the three-part structure you just completed. Measure the inner height of the three-part section from the floor to where the top section meets the wall section. Measure the inner width from the place where the top meets one wall to where it meets another. Subtract 3 inches from the inner height measurement and cut two sections this size. Cut one section to the dimension of the inner width. Use the installation guide to find the measurements of the other support sections of the front frame -- this will vary based on your particular fireplace.

Position the section cut to the inner width dimension over the two sections cut using the inner height measurement. Screw through the ends of the pieces to connect them. Flip the unit upside down with the help of a friend and build the rest of the face according to your fireplace installation guide's manual -- it is vital you follow manufacturer's directions for the front because different fireplaces have varying clearance and support requirements. Install additional studs between the top and bottom boards of the front section at 18- to 24-inch intervals if the width of any open section is more than 3 feet.

Screw the front section you just completed using the manufacturer's diagram to the three-sided section you set aside earlier. Set the front section flush within the sides of the structure so that no part protrudes. Screw the front to the three-sided section through the sides of the front, placing two screws each per side at the top, bottom and middle. Position the unit in the prepared fireplace location. Attach the unit to the wall through each stud that touches it and to the floor through the boards around the base.