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HomeMy WebLinkAbout08/08/2018 - Landmark Preservation Commission - Agenda - Work SessionMeg Dunn, Chair City Council Chambers Alexandra Wallace, Vice Chair City Hall West Michael Bello 300 Laporte Avenue Katie Dorn Fort Collins, Colorado Kristin Gensmer Per Hogestad Kevin Murray Mollie Simpson Fort Collins is a Certified Local Government (CLG) authorized by the National Park Service and History Colorado based on its compliance with federal and state historic preservation standards. CLG standing requires Fort Collins to maintain a Landmark Preservation Commission composed of members of which a minimum of 40% meet federal standards for professional experience from preservation-related disciplines, including, but not limited to, historic architecture, architectural history, archaeology, and urban planning. For more information, see Article III, Division 19 of the Fort Collins Municipal Code. The City of Fort Collins will make reasonable accommodations for access to City services, programs, and activities and will make special communication arrangements for persons with disabilities. Please call 221-6515 (TDD 224-6001) for assistance. An audio recording of the meeting is available upon request. Work Session August 8, 2018 5:30 PM • CALL TO ORDER • ROLL CALL • REVIEW OF ITEMS FOR CONSIDERATION AT THE NEXT REGULAR MEETING TO BE HELD ON WEDNESDAY, AUGUST 15, 2018 AT 5:30 P.M. IN CITY COUNCIL CHAMBERS CONSENT 1. Consideration and Approval of the Minutes of June 20, 2018 Regular Meeting 2. 233 North Loomis Avenue - Final Demolition/Alteration Review DISCUSSION 3. Evans/Reidhead Property, 707 West Mountain Avenue Landmark Designation 4. Trimble/Taylor/Dixon Property 817 West Mountain Avenue Landmark Designation 5. Patterson House, 121 N Grant Avenue, Nomination to the National Register of Historic Places 6. 221 East Mountain - Final Development Review 7. Downtown and Transition Areas Code Updates and Recommendation to City Council • POLICY AND LEGISLATION Discussion of Development Review and Compatibility Codes Landmark Preservation Commission • BOARD TOPICS LPC Work Plan – Priorities and Progress TICRAT Workshop Review • OTHER BUSINESS • ADJOURNMENT DATE: STAFF: August 8, 2018 Karen McWilliams, Historic Preservation Planner WORK SESSION ITEM Landmark Preservation Commission SUBJECT FOR DISCUSSION Discussion of Development Review and Compatibility Codes EXECUTIVE SUMMARY The purpose of this item is to discuss the historic preservation codes and processes related to the review of development and new construction abutting or adjacent to historic properties. GENERAL DIRECTION SOUGHT AND SPECIFIC QUESTIONS TO BE ANSWERED At this Work Session, the LPC will be discussing proposed code revisions to the Land Use Code pertaining to the review of new construction and development abutting or adjacent to historic properties. The Commission’s comments will be used to further develop tailored code language. Questions for discussion include: Does the LPC agree with or disagree with staff's language on the chart? Does the LPC have additional suggestions or recommendations for improvements? BACKGROUND / DISCUSSION Building upon the comprehensive review of historic preservation policies completed in 2014, the Historic Preservation Division has contracted with Clarion Associates to analyze the relevant codes and processes in the City's Municipal Code and Land Use Code. ATTACHMENTS 1. 3.4.7 Code Chart- with Feedback (PDF) 2. Historic Preservation LUC 3.4.7 graphics (PDF) 3. Staff Presentation (PDF) Packet Pg. 3 a Packet Pg. 4 Attachment: 3.4.7 Code Chart- with Feedback (7022 : Discussion of Development Review & Compatibility Codes) 1 3.4.7 b Packet Pg. 5 Attachment: Historic Preservation LUC 3.4.7 graphics (7022 : Discussion of Development Review & 2 3.4.7 b Packet Pg. 6 Attachment: Historic Preservation LUC 3.4.7 graphics (7022 : Discussion of Development Review & 3 3.4.7 b Packet Pg. 7 Attachment: Historic Preservation LUC 3.4.7 graphics (7022 : Discussion of Development Review & 4 3.5.1 b Packet Pg. 8 Attachment: Historic Preservation LUC 3.4.7 graphics (7022 : Discussion of Development Review & Historic Preservation Code Updates 1 Landmark Preservation Commission August 8, 2018 Key Changes Current • No defined area of adjacency • Criteria promotes sameness • Non-consensual: three meetings required • Initial eligibility decision without full information • Confusion on imminently dangerous Proposed • 200-foot buffer • Criteria promotes flexibility • Now two meetings before Council decision • Initial eligibility decision based on survey • Clarity on imminently dangerous 2 c Packet Pg. 9 Attachment: Staff Presentation (7022 : Discussion of Development Review & Compatibility Codes) Additional Improvements • More options for quick approval • Staff and LPC approval with conditions • LPC Design Review Subcommittee • Interactive GIS map • Demolition permit tied to building permit • Reformat code; add graphics and references • Flowcharts and handouts; webpage improvements • District‐specific design standards 3 4 c Packet Pg. 10 Attachment: Staff Presentation (7022 : Discussion of Development Review & Compatibility Codes) 5 6 c Packet Pg. 11 Attachment: Staff Presentation (7022 : Discussion of Development Review & Compatibility Codes) 7 8 c Packet Pg. 12 Attachment: Staff Presentation (7022 : Discussion of Development Review & Compatibility Codes) 9 Historic Preservation Code: Next Steps July –November Additional Outreach Aug. 1, Oct. 3, Nov. 7 Citizen Advisory Committee Mtgs. Aug. 8 Downtown Business Association Aug. 9 Downtown Development Authority Nov. 14 Landmark Preservation Commission Nov. 15 Planning and Zoning Board Dec. 4City Council 1st Reading Dec. 18 City Council 2nd Reading c Packet Pg. 13 Attachment: Staff Presentation (7022 : Discussion of Development Review & Compatibility Codes) DATE: STAFF: August 8, 2018 Maren Bzdek, Historic Preservation Planner WORK SESSION ITEM Landmark Preservation Commission SUBJECT FOR DISCUSSION LPC Work Plan - Progress and Priorities EXECUTIVE SUMMARY City Code requires all boards and commissions to file work plans on or before September 30 for the following year. According to the Boards and Commissions Manual, work plans should set out major projects and issues for discussion for the following year. The LPC adopted the attached 2018 work plan at its August 16, 2017 meeting. Beginning with the September 13, 2017 work session, consideration of pending priorities associated with the work plan will be a regular discussion item. The regular recurrence of this discussion item is intended to provide the Commission with the opportunity to measure ongoing progress and identify action items. ATTACHMENTS 1. LPC 2018 Work Plan signed (PDF) Packet Pg. 14 a Packet Pg. 15 Attachment: LPC 2018 Work Plan signed (7009 : LPC Work Plan - Progress and Priorities) a Packet Pg. 16 Attachment: LPC 2018 Work Plan signed (7009 : LPC Work Plan - Progress and Priorities) TICRAT Taller Internacional de Conservacion y Restauracion de Architectura de Tierra (International Workshop on the Conservation and Restoration of Earthen Architecture) Pecos, NM June 2018 Figure 1: Remnants of Cathedral built in 1688 + at Pecos Natl Park. Presented By: University of New Mexico (UNM), National Park Service (NPS), Instituto Nacional de Antropologica (INAH – Mexico), University of Arizona (AU), Cornerstones Community Partnerships. Purpose: to bring much-needed information to communities and professionals in the preservation of historic earthen structures. Workshop consisted of 3 days of lectures and hands-on practice in earthen materials and their maintenance. Lecture subjects covered: • Theory of earthen Architecture, including theories of failed repair. • History and discovery of historic adobe construction by the native and Spanish peoples of colonial New Mexico • Dealing with catastrophic failure, including earthquakes, in earthen architecture. TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 17 • Preservation Intervention in stabilizing historic buildings. • Historic Finishes for earthen structures. Hands-on subjects included: • Best practices of the NPS, including rebuilding and capping walls, mud plaster, mortar replacement, basal repair. • Plaster finish systems and lime wash application. • Using pigments, soap and alum in the curing process, for both decoration and weatherproofing . The TICRAT Workshop continued our education in earthen construction (known locally as Adobe Construction) and its limitations. Dr. Luis Fernando Guerrero (Universidad Autonoma Metropolitana Mexico City) talked about how encasing softer materials in a harder, protective shell can cause more problems than it can help. Part of his presentation showed a concrete shell placed on an old Adobe wall. The photo showed that the material to be protected had deteriorated at an increasing rate while covered with the concrete; leaving only the shell of concrete to show the outline of what was. In a building system, the softer material will always be the sacrificial. Haydee Orea (INAH) explained the different historical finishes for Adobe, including the different layers of finish applied and at what time in the cycle they would be best applied. Antonio Guerrero (INAH) did a presentation on structures affected by an earthquake, and how they are repaired. He explained how to inject lime mortar to repair earthen structures. One of our field trips took us to an adobe house with many failures. We studied the house as a Structural Survey and discussed what we had found. Later we talked about how to mitigate the problems we had found. Of note, much of what is used in Adobe (earthen) construction translates to many building systems in our area. Many of our historic buildings through the first half of the 20th Century were made with more local materials. These include quarried stone, locally manufactured soft brick, sand and lime. Much of Adobe work deals with the hardness of material and its relation to the hardness of other materials. This translates well to Fort Collins not only in our preservation of existing Adobe structures but also in dealing with our historic natural materials. TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 18 Figure 2: Making Adobe block the easy way. This relates to our softer brick and stone work here. Our old, structural brick buildings were mostly made of a local brick that was not compressed and hard fired. To make sure wall fabric did not deteriorate, a softer mortar was used of lime and sand. This is the sacrificial element that deteriorates first; saving the brick to be repointed. Often engineers do not approach existing masonry this way. Some will see the deterioration of the mortar and order a repoint with a harder mortar (type M or S) to gain better compression strength. This can cause the brick to deteriorate while the masonry joint stays intact. Old Stone foundations are usually made of a finished outside (tooled) stone with a rubble interior, held together with a lime and sand mortar mix. Since the stone is harder than our typical traditional brick, a slightly harder mortar is occasionally used as a tuck-point. That way the mortar does not deteriorate as quick as the brick joint, and preserves the soft mortar inside. This can be seen in how the NPS often preserves historical adobe. Their system is to cover the existing with a new layer of adobe and cap the wall with a mixture that has a hardening additive, to shed moisture. However, they have found that this hardener can cause some adverse reactions. Natural adobe mud will crack in the heat and heal itself with rain. The hardener, however cracks in the heat and does not heal itself when moist, causing more moisture to get inside the wall system. Since the additive is not usually added to the side finish, much of this moisture can still evaporate out the sides. They are now testing walls to see if the additive has long term adverse effects to the wall system. Locally, we have adobe-built homes and buildings in what we call the Alta Vista-Buckingham- Andersonville area of the City. Of these one is known as the Museo de las Tres Colonias, also known as the Romero House. The City is looking for good practices to maintain this building. The outside has two problems. These are standard to the type of construction: • The adobe block and finish is spalling right above ground level. • The soft earthen finish deteriorates to need of replacement every two years or so. TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 19 During the Workshop, we talked about mixes of materials, in both structure and finish. Both are needed in the Romero House rehabilitation. Locating soil was not covered, but the ratio of clay to dirt was (20%- 25%). The amount of water to be added was important too. Mud was tested for length before calving. A longer calving (stiffer) mix was best for adobe block while the least was better for a finish. I removed some excavated soil on site of the new subdivision, south of the Romero Home. The soil there was good enough to be used to patch the adobe. Standard testing of soils for qualification was noted, but expected to be common knowledge. Samples of soil were shown after being diluted and agitated, to show the contents of aggregate, clay binder and silt. New tests were explained by Dr. Guerrero Baca to help decide what soils are good to either make adobe block, use as mortar or use as a protective finish. Figure 3: Different soil samples including calving rods (churros) to the right. On wall finishes, the different layers of finishes were discussed. Like in a three part plaster system, first start with a scratch coat (rough), adding a medium (brown) coat and adding a durable finish coat. This finish coat will be less durable and will calve quicker than a stiff adobe brick, or mortar mix. Many adobe houses have a lime infused plaster finish to help shed water and be more durable than a soil only mix. The Romero House has a soil finish with natural clays. The original finish was removed and not analyzed. The theory is that the home would have had a clay soils only finish, ignoring the lime piles across the street brought to help in making sugar at the plant across the street. TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 20 Figure 4: 3 stages of lime plaster. L-medium coat, M-scratch coat, R-finish coat. The City has future talks with specialists from Cornerstones to figure a correct finish. It’s likely that any finish will take regular maintenance. Talk is of an annual schedule with the neighborhood to do repairs. Of note, but not of importance to our City: • The site we worked on is the ancestral home of the Jemez Pueblo people. • Black brick (with ash) were made in a short period of time (1620 – 1640). All the rest were made of the local red soil. • Colonial adobe brick were a different size than the native. Colonial (mission) brick were 20 x 10 x 4in. block while local brick are 14 x 10 x4in. • Pumice is used as a rough additive for hardening and grit. • In further south structures, Adobe may have been used as a roofing, being able to seal out moisture. These finishes are made by adding lime, soap (lye) and Alum. A mixture of these can seal a mud roof for up to three years without repair, The need for repair can be judged by throwing water on the material and seeing if the moisture soaks in or is repelled. A new coat can be applied over the existing when needed. • Cactus gum is used to slow curing and allow for a more pliable installation. • When Adobe finish starts to delaminate from the block, a lime injection behind the finish can help re-adhere the finish. • Hydraulic mortars and finishes were discussed. The conversation about true lime mixes was talked about as certain countries believe only their limes are the only pure mixes (England, Spain, etc.) . Local western hemisphere limes have been used for centuries, it was pointed out. Hydrated limes are best slaked for at least a month. Most of the work during the Workshop involved Type S Lime, to speed up the process. TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 21 Figure 5: Placing the brown (medium) coat over the rough coat. Kevin Murray June 2018 TICRAT WORKSHOP REVIEW Attachment: TICRAC Workshop Review - Kevin Murray Packet Pg. 22