The foundation (or footer) for a masonry fireplace is usually made of reinforced concrete poured below local frost, or at least 12" below undesturbed ground in frost free areas. If the fireplace is built in a house with a slab-on-grade foundation, the slab under the fireplace and extending 6" outside the fireplace walls must be 12" thick. 2003 International Residential Code (IRC) R1001.1.1 Support. Masonry chimneys shall be supported on foundations of solid masonry or concrete at least 12 inches (305 mm) thick and at least 6 inches (152 mm) beyond each side of the exterior dimensions of the chimney. Footings shall be founded on natural, undisturbed earth below the frostline. In areas not subject to freezing, footings shall be located a minimum of 12 inches (305 mm) below finished grade. Minimum dimensions of the foundation (footer or thickened slab) and the stem wall (fireplace wall) are listed for each size of certified Buckley Rumford fireplace in the table below: R30 (30" Rumford) - foundation 5'-6" x 3'-0" - stem wall 4'-6" x 2'-0" R36 (36" Rumford) - foundation 6'-0" x 3'-4" - stem wall 5'-0" x 2'-4" R42 (42" Rumford) - foundation 6'-6" x 3'-4" - stem wall 5'-6" x 2'-4" R48 (48" Rumford) - foundation 7'-0" x 3'-8" - stem wall 6'-0" x 2'-8" The actual size of the foundation needed to support the fireplace and chimney depends on the construction materials and design. Usually the foundation, stem wall and fireplace wall must be more than the minimum depth if the chimney is built on the outside of an exterior frame wall. If in doubt read Step 11 on chimneys in the Instructions.

TECHNICAL SERVICE	MANUFACTURER
Buckley Rumford Co. 1035 Monroe Street Port Townsend, WA 98368 360 385 9974 or 360 531 1081 buckley@rumford.com	Superior Clay Corporation P.O. Box 352 Uhrichsville, Ohio 44683 ‭740 922 4122‬ sales@superiorclay.com

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Buckley Rumford Fireplaces
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