HomeMy WebLinkAboutItem 2 - Covelop, SWCA - Old Gas Works Project_Review of Historical Project Conditions_2025-10-17
October 17, 2025
Hannah Hanh, Associate Planner
Community Development Department
City of San Luis Obispo
919 Palm Street
San Luis Obispo, California 93401
Submitted via email: hhanh@slocity.org
Re: Response to Cultural Heritage Committee Approval Conditions proposed for the Old Gas
Works Mixed Use Development Project, 280 Pismo Street (Application No. ARCH-0451-2024)
Dear Hannah Hanh:
SWCA Environmental Consultants (SWCA) has continued to work with CoVelop Collaborative
Developments (CoVelop) on the proposed Old Gas Works Mixed-Use Development Project (project),
which involves the rehabilitation and reuse of the historic Gas Works building located at 280 Pismo
Street. In response to the recent City of San Luis Obispo’s (City’s) Cultural Heritage Committee (CHC)
hearing on August 25, 2025 where the project was reviewed and committee members provided proposed
recommendations for conditions of the project’s approval. In response to some of those conditions,
CoVelop prepared a letter that was addressed to members of the City’s Architectural Review Committee
(ARC) that spoke to the nuances of the proposed conditions outlined by the CHC. As the qualified
architectural historians and historic preservation consultants for the project, CoVelop has provided this
letter (see Attachment A) to SWCA for our review and consideration within the overall purview of
potential impacts related to historical resources.
After reviewing this letter, the conditions outlined in the meeting minutes for the August 28, 2025 CHC
hearing, and SWCA’s Historic Preservation Report for the project as revised in August 2025, SWCA has
prepared the following letter to address specific conditions and how they relate to the overall preservation
of the resource in accordance with the Secretary of the Interior’s Standards for Rehabilitation
(Rehabilitation Standards) and City policies pertaining to historic preservation.
Condition 1. The addition to the Old Gas Works shall be constructed using
materials represented in the development application to clearly
differentiate the addition from the existing building.
As outlined in the analysis provided by SWCA’s Historic Preservation Report, revised for August 2025,
the proposed new additions to the Old Gas Works building as currently designed are both compatible and
differentiated from the historic fabric of the historical resource. Additionally, the additions will be
constructed in such a way that their removal in the future would not impact the material integrity of the
Old Gas Works building. Therefore, the project as envisioned and designed meets Rehabilitation
Standards 9 and 10, and this condition identified by the CHC.
Response to Cultural Heritage Committee Approval Conditions proposed for the Old Gas Works Mixed Use
Development Project, 280 Pismo Street (Application No. ARCH-0451-2024)
2
Condition 2. A replica of the historic lunette that includes a muntin pattern
which matches the original window (alternate materials may be
considered) shall be installed above the entrance in the original
doorway.
As outlined in SWCA’s Historic Preservation Report and CoVelop’s letter to the ARC, part of the issue
related to the reuse of the original lunette stems from the previous structural retrofit work which has
altered the overall dimensions of the Pismo Street entrance such that the lunette would no longer fit
within the opening, and that the clearance from the lunette for patrons would be reduced and result in
various problems from both a perspective of usability and overall design and aesthetics. Furthermore, the
design of replica lunette does not necessarily comply with the Standards for Rehabilitation, specifically
Rehabilitation Standard 3 which discourages creating a false sense of historical development. Although
the lunette was an original and character-defining feature of the Old Gas Works building, installing a
recreationist lunette as part of the proposed project would be done so in a way that is reflective of the
current conditions of the entrance opening that has been significantly altered. This would affect the
overall scale, appearance, and character of the primary entrance that is a significant departure from the
original conditions. In turn, this would affect the building’s integrity of design, which is an essential
aspect of integrity to the building’s overall historical significance as an example of Mission Revival
architecture. While there is no doubt that the CHC recommendation is coming from a place of concerned
stewardship, the addition of a replica lunette within the current entrance opening of the building would
prove more detrimental to the building’s ability to convey its significance rather than enhancing it, as
intended. The proposed storefront approach outlined by CoVelop is entirely compliant with the Standards
for Rehabilitation in that it will be composed of industrial materials and feature an overall muntin pattern
that is consistent with traditional forms, while also being differentiated from the historic fabric as a
contemporary intervention. This, coupled with the retention and preservation of the original lunette at the
building alongside interpretive materials, is an appropriate approach to retaining the historic character of
the building and complying with all of the Standards for Rehabilitation.
Overall, SWCA recommends that this condition be reconsidered and removed as part of the project’s
approval as it may result in unintended impacts to the historical resource.
Condition 3. The City Arborist shall review the final landscape plans to ensure
that landscaping will not cause damage to the Old Gas Works
building.
There are no additional considerations related to this condition.
Condition 4. Landscaping materials (e.g., pavers, flagstones, low walls,
boulders, or other masonry) that are compatible or
complementary with the Los Berros (Caen) stone shall be
incorporated.
Generally, there are no additional considerations related to this condition. However, we recommend that
the use of materials that reflect the character-defining material at the building should be done so in a way
avoids creating a false sense of historical development at the property where such materials never
incorporated into the landscape. Further review of the landscape plan, particularly under Rehabilitation
Standards 2 and 9, may be required.
Response to Cultural Heritage Committee Approval Conditions proposed for the Old Gas Works Mixed Use
Development Project, 280 Pismo Street (Application No. ARCH-0451-2024)
3
Condition 5. Any replacement roof materials or design shall be consistent with
the roof design and material of the Old Gas Works from its period
of significance.
The period of Significance identified for the Old Gas Works building is from 1904 to 1918, which
corresponds with its historical significance under both California Register of Historical Resources
(CRHR) Criterion 1 and Criterion 3. As demonstrated in SWCA’s August 2025 report, the Old Gas
Works building roof underwent multiple alterations during that period, which included the addition of
skylights and smokestacks. While some documentation noted that the original roof as either corrugated
iron or “imitation mission tile roofing of iron,” documentation was generally inconclusive. A review of
the Sanborn Fire Insurance Map did not provide further information related to the roof materials;
however, photographic evidence from the period of significance appears to show varied conditions that
evolved over this timeline where the building achieved its historical significance from 1904 until 1918.
Although CHC member comments were specific about finding a replica from a very specific photograph
of poor quality and indiscernible resolution, the variation reflected in the period of significance in other
photographs dating to the period of significance suggests that the use of typical corrugated metal roof
would be appropriate to the period of significance and meet the language outlined in this condition, as
well as the Standards for Rehabilitation. This is most evident in a photograph of the building from 1911,
which appears to show the undulations of corrugated metal roofing, as well as areas along the periphery
of the corrugated panels that are lifting and bent in a manner that is typical of corrugated metal roofing
(Figure 1). The conditions exhibited in this photograph, among others that date to the period of
significance, are consistent with the design of the project as currently envisioned and proposed.
Therefore, SWCA believes that the current design satisfies this condition as written.
Figure 1. 1911 photograph of the Old Gas Works building that dates to the period of significance (1904-
1918) with what appears to be corrugated metal roofing. This is evident in the undulations of the roofing
throughout, as well as the damage exhibited at the corners of one of the panels, which appears to be
lifting and bent in a manner consistent with typical corrugated roof materials.
SUMMARY
Upon reviewing the conditions put forward by the City’s CHC, as well as the CoVelop letter to the City’s
ARC, SWCA and our team of qualified architectural historians have completed a review of the proposed
conditions in relation to the overall design and execution of the project. Generally, SWCA finds that the
Response to Cultural Heritage Committee Approval Conditions proposed for the Old Gas Works Mixed Use
Development Project, 280 Pismo Street (Application No. ARCH-0451-2024)
4
proposed project complies with the Standards for Rehabilitation and other City policies pertaining to
historic preservation. The proposed project as designed also satisfies CHC’s Condition 1 (differentiated
addition) and Condition 5 (roof materials and design), and meeting Condition 3 (arborist review) and
Condition 4 (landscaping materials) is easily achievable within the context of the Standards for
Rehabilitation and further coordination with the City. However, Condition 2 (replica lunette) has the
potential to result in inadvertent impacts to the historical resource through alteration of its historical
integrity and creating a false sense of historical development. As outlined above, and in our August 2025
Historic Preservation Report, the current design for the primary entrance and the approach of salvaging
and preserving the original character-defining lunette window alongside interpretive materials is
compliant with the Standards for Rehabilitation and is an overall savvy preservation approach that would
retain this important feature in the context of the building, one which will be clearly defined for visitors,
while also allowing for the buildings reuse in a manner that would not create a false sense of historical
development. As such, it is SWCA’s opinion that the CHC’s condition pertaining to the installation of a
replica lunette be reconsidered and removed as the current design and approach better satisfies the
Standards for Rehabilitation and would avoid any inadvertent impacts to the historical resource.
Sincerely,
Daniel Herrick, M.H.C.
Principal Architectural Historian/ Historic Preservation Planner
Attachment A: CoVelop letter to the City’s Architectural Review Committee “Project Gasworks Mixed
Use Development Pismo & Walker St. San Luis Obispo, Application Number: ARCH-
0451-2024.”
X-1
ATTACHMENT A
CoVelop letter to the City’s Architectural Review Committee
“Project Gasworks Mixed Use Development Pismo & Walker St. San
Luis Obispo, Application Number: ARCH-0451-2024.”
Project: Gasworks Mixed Use Development
Pismo & Walker St. San Luis Obispo
Application Number: ARCH-0451-2024
Dear Architectural Review Committee Members,
We would like to share our concerns and address several proposed conditions outlined in the
staff report for this project. As you know, the Cultural Heritage Committee (CHC) reviewed the
project on August 25. Some conditions recommended by the CHC were carried forward into the
ARC staff report; however, because public comment had already closed, we were not able to
provide input at that time. We believe that, had we been able to engage in dialogue, these
conditions would have been adjusted to be more practical. We would now like to address each
item for context and consideration.
Black “Steel” Storefront Window/Door Systems
During CHC deliberations, our objections regarding the “steel” storefront requirement were
confused by the CHC and not addressed. Steel was not historically used in these door openings,
and requiring it would not be appropriate. Instead, we propose to use a high-quality metal (Steel
or Aluminum) product for both the storefront and skylights. We understand and share the city’s
interest in these door/windows being high quality but specifying that they must be steel is
needlessly expensive and burdensome. There are many examples of Aluminum storefront
systems with narrow mullions that would look great in this application.
Replica of the Historic Lunette Window in the Original Location
We agree with the requirement to display the original lunette window inside the building,
accompanied by historic photographs and an explanatory note. However, installing a replica
lunette directly next to the preserved original in the original location raises several concerns:
• Structural limitations: Once a concrete slab is added, the height of the existing opening
will not accommodate a standard 6’8” door much less a 7ft.-8 ft. door that would be
consistent with this commercial application. This is the front door of the commercial
space, essentially the future business’s first impression to the public. It has to be of scale
and quality that is inviting and promotes the success of the business. Adding a faux
metal lunette window in the arch while modestly raising the floor for nuisance flood
issues simply does not leave enough height to have an appropriately sized front door.
Furthermore having the replica window within a few feet of the real original window is
odd and contradictory to SOIS standards. See exhibit below for clarification.
• Standards compliance: Adding a replica would conflict with the Secretary of the
Interior’s Standards (SOIS), specifically Standard 3, which prohibits creating a “false
sense of history” by imitating earlier styles. The enclosed Appendix expands on this.
Instead, we propose a durable, aesthetically compatible metal storefront system, an example of
which is below.
Landscaping Materials
Our priority is to select materials that meet requirements for stormwater infiltration, ADA
compliance, and aesthetic compatibility. If a complementary color tone can be used to harmonize
with the Los Berros stone of the historic building, we are open to the recommended condition.
Roofing Materials
The CHC recommendation was based on one photograph that appeared to show a roof with
significant undulation. However, the majority of the historic photos (8–10 in total) depict a
standard corrugated metal roof, which we propose for the existing historic building.
Additionally, we have been unable to locate a roofing profile that matches the one suggested by
CHC.
Adding Features to the Residential Building
The addition of new architectural features—such as diamond-shaped quatrefoil vents—as an
homage would similarly conflict with SOIS Standard 3 by creating a false historical impression.
The intent of the standard is to preserve authentic character-defining features without introducing
imitations. An appendix with further SOIS explanation is enclosed for reference. In light of this,
the design is proposed to remain as is.
West Elevation – Community Design Guidelines
Revisions to the west elevation were submitted to the Planning Department in April, including a
mix of materials and textures however unfortunately the rendering was not updated to reflect the
change. The staff report noted that the ARC committee should discuss whether the west
elevation is consistent with community design guidelines, and we believe the revised elevation is
consistent. The rendering has also been updated and is enclosed for your review.
We respectfully request that you consider providing the following modified recommendations to
address the above CHC conditions and allow applicant participation during ARC discussions.
Requested Condition Modifications
• Storefront Window/Door system:
o Staff recommendation: Custom Black Steel Storefront System
§ Requested modification: Black Metal Storefront System
• Lunette Window:
o Staff recommendation: replica of the historic lunette that includes muntin pattern
to be installed in original location
§ Requested Modification: Eliminate this requirement while keeping the
requirement to display the original lunette window on the interior only
• Landscaping materials
o Staff recommendation: Pavers, flagstone, boulders etc. be compatible with the
Los Berros Stone
§ Requested Modification: Hardscape to have color compatibility only, but
not to match.
• Roofing materials
o Staff recommendation: replace roofing materials to be consistent with its period
of significance
§ Requested Modification: Roofing materials to be corrugated metal
• Architectural features
o Staff recommendation: Add features to the residential building that pay homage to
the historic gasworks building
§ Requested Modification: Leave residential architecture as is designed
because SOIS does not support using architectural features as
recommended.
These modified recommendations will ensure that thoughtful and historically suitable design
considerations can be incorporated into the project in a practical manner and appropriately
considered during the Director’s decision hearing.
Thank you for your time and consideration.
Sincerely,
Damien Mavis
Secretary of Interior Standards Appendix
Historic Replica6on and Lune9e Window Treatment
We appreciate the Commission’s though3ul review and the sugges8on to replicate elements of the Old
Gas Works building within the new construc8on. However, per the Secretary of the Interior’s Standards
for Rehabilita6on, replica8on of historic materials or features within new construc8on is not
recommended and may conflict with established preserva8on principles.
• Standard 3 states that “Each property will be recognized as a physical record of its 7me, place,
and use. Changes that create a false sense of historical development, such as adding conjectural
features or elements from other historic proper7es, will not be undertaken.” Replica8ng por8ons
of the Old Gas Works in the new residen8al structure risks crea8ng a false sense of historic
con8nuity and blurring the dis8nc8on between the authen8c historic resource and the new
building.
• Standard 9 emphasizes that “New addi7ons, exterior altera7ons, or related new construc7on
shall not destroy historic materials, features, and spa7al rela7onships that characterize the
property. The new work shall be differen7ated from the old and shall be compa7ble with the
historic materials, features, size, scale and propor7on, and massing.” Compa8bility is achieved
not through imita8on or replica8on, but through though3ul design, materials, and scale
rela8onships that respect the historic structure without copying it.
• Standard 10 clarifies that new construc8on should be designed so that if removed in the future,
the essen8al form and integrity of the historic property would remain intact. Replica8ng original
features in new construc8on risks confusing future interpreta8on of what is historic versus what
is new.
Accordingly, while we support the idea of paying homage to the Old Gas Works building, we recommend
doing so in a manner that is compa6ble but differen6ated, such as through the use of complementary
materials & textures (e.g., terracoJa stone with tonal similarity to Los Berros stone & metal siding and
roofing). This approach allows the new construc8on to acknowledge the historic resource without
diminishing its authen8city.
Lune9e Window Treatment
The exis8ng historic luneJe window has been retained and remains intact; however, due to structural
reinforcement of the opening with new steel framing, it can no longer be reinstalled in its original
loca8on. To ensure compliance with the Secretary of the Interior’s Standards:
• In accordance with Standard 2 (retaining and preserving dis8nc8ve features) and Standard
10 (reversibility of altera8ons), the luneJe window will be carefully preserved and displayed in
the interior of the rehabilitated building.
• By preserving the original window as an interpre8ve element within the interior, the project will
provide the public with a tangible connec8on to the building’s history while avoiding a false
sense of replica8on or conjecture.
This approach preserves the ar8fact, honors the building’s historic character, and remains fully
consistent with the Secretary of the Interior’s Standards for Rehabilita6on.
Conclusion and Local Policy Alignment
The proposed treatment strategy aligns not only with the Secretary of the Interior’s Standards but also
with the City of San Luis Obispo’s Historic Preserva6on Program Guidelines, which call for preserva8on
of authen8c historic features, avoidance of conjectural reconstruc8on, and clear differen8a8on of new
work. By carefully preserving the luneJe window within the renovated interior and incorpora8ng
compa8ble but differen8ated materials in the new construc8on, the project will celebrate the Old Gas
Works building’s history while maintaining architectural integrity and compliance with both federal
standards and local preserva8on policy.
+/- 8"6'-8' MIN. REQUIRED5'-7"6'-9"4'-1"10'-10"(N) OPENING WIDTH7'-8"(E) HISTORIC WINDOW, REINFORCED OPENING NO LONGER ALLOWS FOR WINDOW TO FIT WITHIN THE OPENING(E) WALL OPENING(E) STEEL REINFORCEMENTPROPOSED FLOOR LEVEL(E) GRADEHORIZONTAL SUPPORT FOR (E) WINDOW, INSUFFICIENT HEAD HEIGHT FOR DOOR(E) OPENING WIDTH8'-3"(E) STEEL REINFORCEMENTEXISTING OPENINGLUNETTE WINDOWEX1MAY 14, 2025GAS WORKSSAN LUIS OBISPO, CAA23079LUNETTE WINDOW EXHIBIT