Review of Miratec Smooth Select Composite Building Trim

District: Various

Owner: Gulf States Construction

Rating: Unrated (New Construction)

Applicant: Josh Murphey - Gulf States Construction

Description: Review of Miratec Smooth Select composite building trim for Staff-level approval at new construction projects.

HDLC Guidelines:

Section 6, Page 3 of the Guidelines for Exterior Woodwork indicates that although the HDLC strongly recommends the preservation of existing wood ornament and trim at historic buildings, it recognizes that in limited conditions, a replacement material that is less susceptible to rot might be an acceptable alternative. The HDLC provides greater flexibility when considering alternate materials for trim and ornament at new construction and additions to historic buildings when the final appearance is identical to painted wood. For an alternate material to be considered as matching wood, the dimensions, profiles and detailing must be identical to the historic wood element. In addition, it must be a solid material that is not subject to shrinkage or warping, with a smooth, field-painted finish that matches painted wood in color and sheen. At historic buildings, alternate trim and ornament materials are typically not appropriate for window and door surrounds, corner boards, fascia or soffits, although they can be considered for additions and new construction. Additionally, dimensional lumber or pressure treated wood is never an appropriate material for trim or ornament.

Previous ARC Recommendations:

07/19/2022: The ARC voted to defer this application for additional review. The ARC agreed they are supportive of material alternatives to wood, particularly for their potential advantages against termites and moisture. However, the ARC noted they would need additional product information to make a recommendation. The ARC members were not able to distinguish what elements in the example buildings presented were made of Miratec and which were Hardie, so they requested the applicant prepare a more specific case study to present at the next meeting. The additional materials should include a local project or two (particularly one that has been built and exposed to the elements for more than 4 years), and additional information on how the material holds up in the local climate.

08/16/2022: The ARC voted to recommend conceptual approval of Miratec Smooth Select composite building trim as a staff-approvable alternative to wood trim with the proviso that it only be approved for installation at new construction projects where Hardie trim would otherwise be permitted. The ARC also agreed that:

The major issues seen in the example photographs appeared to be related to improper contractor installation where the manufacturer’s specific instructions were not followed. However, comparable wood elements may experience similar issues, especially those related to water and proximity with other porous materials such as masonry and concrete.
The product appears to have a good density and dimensional stability and may be less averse to water penetration than traditional kiln-fired wood.
Similar Hardie trim products are currently only staff-approvable on new construction projects and in limited locations where the dimensional qualities match the required wood equivalent and where cut and ripped edges are not visible. The ARC agreed that Miratec trim should only be installed where Hardie trim would otherwise be acceptable.

Staff Recommendations:

Staff recommends the Commission vote to ratify the ARC recommendation for conceptual approval of Miratec Smooth Select composite building trim as a Staff-approvable alternative to wood trim only at new construction projects where smooth-finish Hardie trim would otherwise be permitted.