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$Refractory mortar is required by building code for the construction of the internal components of masonry fireplaces (firebox, smoke dome, throat, flue liners, etc.). Refractory mortars are available in 2 forms: Dry Mix and Premix Dry mix refractory mortar is suited for all aspects of masonry fireplace construction where refractory mortar is required. Premix refractory mortar can only be used for components that do not come in contact with weather (i.e. firebox) because it will wash out. Premix refractory mortar should never be used in outdoor fireplace construction.$ $We recommend that firebrick be positioned 4½” x 2½” x 9” (11mm x 6mm x 23mm) (stretchers) as opposed to shiners laid 2½” x 4½” x 9” (6mm x 11mm x 23mm) to yield a high quality, geometrically stable and durable firebox (Fig 6 and 7). Figure 4. Interior Hearth Rough Layout Figure 5. Examples of Approved Refractory Mortar Brands Table 2a. Interior Hearth Dimensions A B C q g 30” Rumford 30” 12.5” 13.5” 57° 123° 36” Rumford 36” 14” 13.5” 51º 129º 42” Rumford 42” 15” 15” 48º 132º 48” Rumford 48” 16” 18” 47º 133º Table 2b. Interior Hearth Dimensions A B C q g 30” Rumford 760 mm 318 mm 343 mm 57° 123° 36” Rumford 914 mm 356 mm 343 mm 51º 129º 42” Rumford 1067 mm 381 mm 381 mm 48º 132º 48” Rumford 1219 mm 406 mm 457 mm 47º 133º Figure 3. Hearth--Plan View 2. Laying the Inner Hearth See Table 2 and Figure 3 for the hearth dimensions that correspond to the Rumford that is being built. Lay out the fire brick on the prepared foundation base so that the bricks cover the inner hearth and accommodate the walls (Fig 4). The floor hearth bricks should just cover the area required by the inner floor and side walls. Mortar inner hearth bricks to the hearth support with an approved refractory mortar using a 1/16” to 1/8” (2-3 mm) joint. Note: Job site prepared fireclay mixes containing Portland and dry milled fireclay do not meet national or state building codes. They do not resist temperature cycling in this application, nor do they possess the necessary acid resistance for this service. Approved refractory mortars (Fig. 5) are required for use in mortar joints for the firebox, smoke dome and flue linings in masonry fireplaces.$

Rumford Fireplace Installation Instructions

1. Foundation and Preparation

Prepare the supporting foundation for a Rumford using the same construction practices as for a traditional masonry fireplace. Figure 1 shows a cross section for a Rumford and how the components fit into the total fireplace. Table 1 lists the minimum hearth base dimensions required for each size of Rumford. As with all masonry construction, the foundation must be adequately designed to support the weight of the fireplace and chimney. Some typical construction designs are shown in Figure 2. Local building codes should be reviewed for specific requirements concerning foundation construction. For the minimum requirements contained in most building codes please refer to BIA Technical Notes on Brick Construction, Residential Fireplace Design 19.

Figure 1. Side Cross Section of a Rumford Fireplace Table 1a. Minimum Hearth Base Rough Dimensions Rumford Size Minimum Width Minimum Depth1 30” Rumford 4’-6” 3’-8” 36” Rumford 5’-0” 4’-0” 42” Rumford 5’-6” 4’-0” 48” Rumford 6’-0” 4’-4” 1Includes outer hearth base Table 1b. Minimum Hearth Base Rough Dimensions (Metric) Rumford Size Minimum Width Minimum Depth1 23” Rumford 137 cm 112 cm 36” Rumford 152 cm 122 cm 42” Rumford 168 cm 122 cm 48” Rumford 183 cm 132 cm 1Includes outer hearth base

Figure 6. Completed Firebox Wall Construction Figure 7. Stretchers (top) vs. Shiners (Bottom) Table 3a. Face Opening Width Height 30” Rumford 30” 27-32” 36” Rumford 36” 32-38” 42” Rumford 42” 38-42” 48” Rumford 48” 42-48” Table 3b. Face Opening Width Height 30” Rumford 762 mm 686-813mm 36” Rumford 914 mm 813-965 mm 42” Rumford 1067 mm 965-1067 mm 48” Rumford 1219 mm 1067-1219 mm

3. Constructing the Firebox

Construct the walls of the firebox according to the dimensions provided in Table 3 that correspond to the size of the fireplace. Use approved refractory mortar maintaining 1/16” to 1/8” (2-3mm) joints. Be sure to use proper back-up behind the firebox with appropriate fill. 75% solid concrete blocks are preferred. Be sure to maintain proper clearances to combustibles throughout construction. See Appendix A for a summary of clearances and other code considerations.

Figure 8. Setting the Rumford Throat Figure 9. Back Walls of Throat Sitting Flush with Fire Brick

4. Setting the Rumford Throat

After completion of the firebox walls, set and mortar the throat to the firebox with refractory mortar (Fig. 8). Note that the fire box walls should be flush with the interior of the throat (Fig. 9). There should be no ledges in the firebox where the throat the brick meet.

7. Setting the 1st Flue Liner and Building the

Chimney

Using refractory mortar, attach the first flue liner to the smoke dome and proceed with normal chimney construction (Fig. 15). If using a round flue liner and transition ring, position and mortar the transition piece onto the smoke dome and proceed with normal chimney construction Recommended flue sizes and transition rings are listed in Table 4. Take care that all interior transitions are smooth and free of mortar and other obstructions to eliminate horizontal surfaces onto which creosote might accumulate during operation. For any questions regarding chimney construction details, please refer to BIA Technical Notes 19b.

Appendix A. Clearance to Combustibles (and other important details to avoid mistakes and code violations)

Note: for outdoor patio fireplaces building codes normally do not apply. Check with your local jurisdiction. Framing All combustibles must be a minimum of 2” away from the masonry If the fireplace is on an outside wall, combustibles must be 4” from the masonry. Framing headers must be at a minimum of 3’0” above the top of the fireplace opening as well as 2” away from the masonry. Fireplace Firebrick must be backed up with 75% solid masonry creating walls minimum of 8” thick. The masonry surrounding the smoke chamber must be a minimum of 6” thick measured from the outside to the interior wall. A non-combustible surround must extend a minimum of 6” beyond the interior face of the fireplace. Chimney The size of flue liner is determined by the inside face opening of the fireplace. The flue cross-sectional area required must be a minimum of 10% of the cross- sectional area of the interior face opening. If using round flues, 8% cross-sectional area may be used. There must be a minimum of 2” airspace between the outside of the flue liner and the chimney wall. The chimney wall must be a minimum of 4” thick solid masonry. The chimney must terminate a minimum of 3’0” from the roof and a minimum of 2’0” from any higher point within 10’ of the chimney. Please see Masonry Chimney Construction document for further clarification.

Figure 10. Building Up the Masonry to Create a Setting Surface of the Damper and Smoke Dome Figure 11. Setting the Damper

Figures 13a and 13b. Setting the Smoke Dome Smoke Dome Dimensions H Base OD Base ID Top OD Top ID 30” Rumford 19” 13”x 35” 11”x 32” 13”x 13” 11”x 11” 36” Rumford 19” 13”x 35” 11”x 32” 13”x 13” 11”x 11” 42” Rumford 30” 13”x 35” 11”x 32” 13”x 17½” 11”x 15½” 48” Rumford 30” 15½”x 35” 13½”x 32” 15½”x 19½” 13½”x 17” Smoke Dome Dimensions (mm) H Base OD Base ID Top OD Top ID 30” Rumford 480 330x890 279x813 330x330 279x279 36” Rumford 480 330x890 279x813 330x330 279x279 42” Rumford 762 330x890 279x813 330x445 279x394 48” Rumford 762 394x890 342x813 394x495 342x432 Figure 14. Smoke Dome Sections for a.) 30” & 36” Rumford--2 pieces, b.) 42” Rumford--4 pieces and c.) 48” Rumford--6 pieces a. b. c. 6. Positioning the Smoke Dome Place the smoke dome onto the prepared flat surface fitting it over the top of the damper. If necessary, adjust the elevation of the smoke dome to insure that the damper opens and closes properly and clears the sides of the smoke dome. The position of the smoke dome can be adjusted front to back or left to right in order to line up with the chimney. Make sure that when the damper is operated that it clears the sides of the smoke dome. Be sure to mortar the smoke dome to the platform and mortar all sections together (Fig. 13a, 13b and 14).

Figure 17. Fireplace Ready for Surround Installation It is important to make sure that the facing does not drop below the front edge of the throat (Fig 18). Dropping below this elevation will impede the airflow and possibly create a smoking situation. Figure 18. Surround Installation Detail Flue Liner Rumford Smoke Dome Flat Damper Firebox Rumford Throat 8. The Surround Complete the surround in the same manner as with any other fireplace (Fig. 17).

5. Preparing a Base and Installing the Flat Damper

Build up the surrounding masonry to match the elevation of the top of the throat (Fig. 10). Place a steel lentil with the first row of masonry that crosses the front of the throat. This further supports the masonry over the throat (Fig. 10). Build up the masonry, preparing a flat surface onto which the damper and smoke dome can be placed and mortared (Fig.11). When setting the damper (Fig 12), make sure that it will operate properly in conjunction with all surrounding masonry. Check and correct for any interferences in opening, closing or overall operation of the damper.

7a. Optional Round Flue Adapter

An adapter piece is available for the 42” and 48” Rumford that will convert the square/rectangle opening on the smoke dome to a round opening that is properly sized for the fireplace (Fig. 16). To install, simply mortar the adapter to the smoke dome and proceed with normal construction using round flues.

IMPORTANT: The instructions provided are intended as a guideline for installing the prefabricated Rumford components as a part of a masonry fireplace. Proper fireplace construction techniques, compliance with building codes and any other requirements are the responsibility of the masonry contractor/installer. Sandkuhl Clay Works, Inc. is not responsible for any errors or misrepresentations that this instruction document may contain or any construction/finished installation problems that may result.

Figure 16. Rectangle/Square to Round Adapter

The 30” and 36” Rumfords do not require an adapter. A 12” round flue nicely fits the 13x13 opening and can be mortared directly to the 36” smoke dome.

Round flue liners, especially in the larger sizes, are significantly less costly and more efficient than the equivalent square/rectangle. Be sure to compare prices.

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Manufacturer of Ceramic, Structural Clay and Refractory Products Since 1912.

Rumford Fireplace

Installation Instructions

1. Foundation and Preparation

We recommend that fire brick be positioned 4½” x 2½” x 9” (11mm x 6mm x 23mm) (stretchers) as opposed to shiners laid 2½” x 4½” x 9” (6mm x 11mm x 23mm) to yield a high quality, geometrically stable and durable firebox (Fig 6 and 7).

$Figure 5. examples of Approved Refractory Mortar Brands$

Table 2a. Interior Hearth Dimensions A B C q g 30” Rumford 30” 12.5” 13.5” 57° 123° 36” Rumford 36” 14” 13.5” 51º 129º 42” Rumford 42” 15” 15” 48º 132º 48” Rumford 48” 16” 18” 47º 133º Table 2b. Interior Hearth Dimensions A B C q g 30” Rumford 762 mm 318 mm 343 mm 57° 123° 36” Rumford 914 mm 356 mm 343 mm 51º 129º 42” Rumford 1067 mm 381 mm 381 mm 48º 132º 48” Rumford 1219 mm 406 mm 457 mm 47º 133º

Figure 6. Completed Firebox Wall Construction

Figure 7. Stretchers (top) vs. Shiners (Bottom)

Table 3a. Face Opening Width Height 30” Rumford 30” 27-32” 36” Rumford 36” 32-38” 42” Rumford 42” 38-42” 48” Rumford 48” 42-48” Table 3b. Face Opening Width Height 30” Rumford 762 mm 686-813mm 36” Rumford 914 mm 813-965 mm 42” Rumford 1067 mm 965-1067 mm 48” Rumford 1219 mm 1067-1219 mm

3. Constructing the Firebox

Figure 8. Setting the Rumford Throat

Figure 9. Back Walls of Throat Sitting Flush with Fire Brick

4. Setting the Rumford Throat

5. Preparing a Base and Installing the

Flat Damper

Figures 13a and 13b. Setting the Smoke Dome

Smoke Dome Dimensions H Base OD Base ID Top OD Top ID 30” Rumford 19” 13”x 35” 11”x 32” 13”x 13” 11”x 11” 36” Rumford 19” 13”x 35” 11”x 32” 13”x 13” 11”x 11” 42” Rumford 30” 13”x 35” 11”x 32” 13”x 17½” 11”x 15½” 48” Rumford 30” 15½”x 35” 13½”x 32” 15½”x 19½” 13½”x 17” Smoke Dome Dimensions (mm) H Base OD Base ID Top OD Top ID 30” Rumford 480 330x890 279x813 330x330 279x279 36” Rumford 480 330x890 279x813 330x330 279x279 42” Rumford 762 330x890 279x813 330x445 279x394 48” Rumford 762 394x890 342x813 394x495 342x432

Figure 14. Smoke Dome Sections for a.) 30” & 36” Rumford--2 pieces, b.) 42” Rumford--4 pieces and c.) 48” Rumford--6 pieces a. b. c.

6. Positioning the Smoke Dome

Place the smoke dome onto the prepared flat surface fitting it over the top of the damper. If necessary, adjust the elevation of the smoke dome to insure that the damper opens and closes properly and clears the sides of the smoke dome. The position of the smoke dome can be adjusted front to back or left to right in order to line up with the chimney. Make sure that when the damper is operated that it clears the sides of the smoke dome. Be sure to mortar the smoke dome to the platform and mortar all sections together (Fig. 13a, 13b and 14).

7. Setting the 1st Flue Liner and

Building the Chimney

Appendix A. Clearance to Combustibles (and other important

details to avoid mistakes and code violations)

Note: for outdoor patio fireplaces building codes normally do not apply. Check with your local jurisdiction. Framing All combustibles must be a minimum of 2” away from the masonry If the fireplace is on an outside wall, combustibles must be 4” from the masonry. Framing headers must be at a minimum of 3’0” above the top of the fireplace opening as well as 2” away from the masonry. Fireplace Firebrick must be backed up with 75% solid masonry creating walls minimum of 8” thick. The masonry surrounding the smoke chamber must be a minimum of 6” thick measured from the outside to the interior wall. A non-combustible surround must extend a minimum of 6” beyond the interior face of the fireplace. Chimney The size of flue liner is determined by the inside face opening of the fireplace. The flue cross-sectional area required must be a minimum of 10% of the cross-sectional area of the interior face opening. If using round flues, 8% cross-sectional area may be used. There must be a minimum of 2” airspace between the outside of the flue liner and the chimney wall. The chimney wall must be a minimum of 4” thick solid masonry. The chimney must terminate a minimum of 3’0” from the roof and a minimum of 2’0” from any higher point within 10’ of the chimney. Please see Masonry Chimney Construction document for further clarification.

The 36” Rumford does not require an adapter. A 12” round flue nicely fits the 13x13 opening and can be mortared directly to the 36” smoke dome.

7a. Optional Round Flue Adapter

2. Laying the Inner Hearth

See Table 2 and Figure 3 for the hearth dimensions that correspond to the Rumford that is being built. Lay out the fire brick on the prepared foundation base so that the bricks cover the inner hearth and accommodate the walls (Fig 4). The floor hearth bricks should just cover the area required by the inner floor and side walls. Mortar inner hearth bricks to the hearth support with an approved refractory mortar using a 1/16” to 1/8” (2-3 mm) joint. Note: Job site prepared fireclay mixes containing Portland and dry milled fireclay do not meet national or state building codes. They do not resist temperature cycling in this application, nor do they possess the necessary acid resistance for this service. Approved refractory mortars (Fig. 5) are required for use in mortar joints for the firebox, smoke dome and flue linings in masonry fireplaces.