Historic Zoning Commission

Old North Knoxville H: Level I/II

3-K-21-HZ

Applicant Request

Level 1 COA issued 3.3.2021: Chimney to be removed to roofline and reconstructed, using original bricks as much as possible and replacement bricks to match and appropriate mortar (work to meet NPS Preservation Brief 2); installation of chimney cap. Removal of existing half-round gutters and replacement in-kind. Repair to wood fascia, soffits, and window trim, including replacement in-kind in patches. Repair to wood lap siding and shingles in gable, including replacement in-kind in patches where necessary. Masonry repair and repointing to foundation (using historically appropriate mortar). Minor repairs to roof cladding surrounding chimney; if replacement is required, new asphalt shingles will replace existing.

Level 2 scope of work, for HZC review 5.20.2021: Proposed replacement of three porch columns: two corner columns on the first-story porch (east and west) and one leftmost (west) corner column on the second-story porch. Two-story porch features six round fluted columns on the first story and five round fluted columns on the second-story porch. Due to water intrusion from weather, failing gutters, and adjacent large trees, three corner columns have rotted. Applicant is proposing the installation of fiberglass reinforced polymer columns instead of wood. On the first-story porch, round fluted columns will measure 9' overall in height and 12" in diameter, with a slight taper to match the existing columns. On the second-story porch, columns will measure 8' overall in height and 10" in diameter. Columns will be smooth-finished on top of square base. Historic capitals to be retained, repaired, and installed on top of new columns. Historic wood railing to be retained.

Conditions of approval identified at 5.24.21 HZC meeting:
1) retain and reinstall existing railings; retain, repair, and reinstall original capitals; and install bases with placement, dimensions, and design to match existing;
2) replacement columns be confirmed to match size, taper proportions, fluting detail of wood columns;
3) confirmation of color, surface texture, and reflective surface to be compatible with the existing columns;
4) information to be provided to staff on column ventilation to minimize expansion/contraction issues which could negatively affect the original capitals.

Site Info

White Columns; George W. Peters House; Chester Kilgore House. Two-story hall-and-parlor Italianate house modified with a kitchen addition c.1878 and a Neoclassical-style remodeling by George F. Barber in 1890s. Cross-gable roof clad in asbestos shingles, exterior of wood weatherboard siding, continuous brick foundation. Two-story Neoclassical porch. Interior brick chimney.

1. 1319 Grainger Avenue is a contributing resource to the Old North Knoxville local overlay and individually listed on the National Register of Historic Places as the Peters House. Built in 1855, the house received a kitchen addition in 1878 and a two-story, Neoclassical style porch as part of a remodeling designed by George F. Barber. The porch was added in the 1890s.

2. The column replacement is part of a broader exterior rehabilitation campaign, and the only element not involving repair to original materials or replacement in-kind. Other work approved in March 2021 involves repair and replacement in-patches to existing wood siding, masonry repair to the chimney, repair to the wood fascia boards, and the installation of a new gutter system.

3. The exterior of the house experienced some deferred maintenance, especially in due to a unique gutter system which ultimately failed and has fed a significant amount of water along the corner columns for several years. The two-story front porch is also surrounded by older-growth maple trees, which contributed to the gutters clogging and water runoff into the columns.

4. The applicant has provided several photos showing the columns' deterioration, especially the rot along the bottom, where the columns would attach to bases. Photos show the east first-story column leaning; the contractor has stated the column was approaching a point where it could not support the second-story porch. The columns were temporarily removed to move forward with porch flooring and gutter repairs.

5. Due to significant deterioration on the corner columns, the applicant is proposing replacement of the corner columns on the first story (east and west), and the west corner column on the second story. Due to the location of the corner columns and their exposure to the elements, the applicant is proposing an alternative material to hollow wood columns.

6. The proposed material is FRP (Fiber Reinforced Polymers), aka fiberglass. NPS Preservation Brief 16, "the Use of Substitute Materials on Historic Building Exteriors," [see attached] notes that FRP is produced as a thin rigid laminate shell formed by pouring a polyester or epoxy resin gelcoat into a mold. Reinforcing rods and struts can be added if necessary, and the gel coat can be pigmented or painted. Fiberglass is a non-load-bearing material attached to a separate structural frame, which can have a "good molding ability and versatility to represent stone, wood, metal, and terra cotta" to be used as "an alternative to ornate or carved building elements such as column capitals, bases, spandrel panels, belt courses" etc (NPS Preservation Brief 16).

7. Preservation Brief 16 notes several advantages to FRP substitutes, including "non-corrosive, rot-resistant," "easily installed," "integral color with exposed high quality pigmented gel-coat or takes paint well," and "high ratio of strength to weight." Disadvantages are listed as "requires separate anchorage system," "combustible, fragile to impact," "high coefficient of expansion and contraction," and "vapor impermeability may require ventilation detail."

8. Similar column replacements were approved in ONK in 2012 and 2013, noting the "painted surface of a composite column is more difficult to discern from the painted surface of a new wood column," and that "new wood or new composite columns would be equally devoid of texture and 'new' in appearance." In February 2020 (2-B-20-HZ), an applicant at 1324 Grainger Avenue proposed a comparable fiberglass replacement column. This application did not include sufficient documentation of deterioration on the columns, so the Commission moved that the applicant explore further repair efforts, and if the columns were unable to be repaired, the fiberglass replacements would be approved. At 1127 Luttrell Street in Fourth and Gill, a similar product was approved in October 2020 (10-C-20-HZ) with the condition that original capitals be retained and wood bases match the existing, and replacement columns match the existing in size and design. These columns have been installed and could be viewed in the field.

9. NPS Preservation Brief 16 notes that "in order to provide an appearance that is compatible with the historic material, the new material should match the details and craftsmanship of the original as well as the color, surface texture, surface reflectivity, and finish of the original material."