Garver Feed Mill Condition Evaluation
OUTLINE Brick masonry overview Condition assessment & methodology Project overview Existing conditions Stabilization Probable costs Summary
BRICK MASONRY OVERVIEW
Brick 4000 years old technology Simple technique of stacking to make walls Strong Long lasting Fire proof
Brick is like a loaf of bread Hard crust outside, Soft core inside
Cross section of early 20 th century mold made brick Swirl is due to kneading of clay before it was set in mold
Cross section of early extruded brick Horizontal lines from extrusion process
Mortar A cushion/seal between bricks/bearing surface Bonding agent/surface enhancer A mixture of cement, sand & lime Sacrificial
HISTORIC MASONRY
Mass Wall Multiple wythes of brick Load bearing Thermal mass
Mass Wall Sheds most moisture Absorbs some moisture Moisture dissipated by movement of heat and by evaporation Soft bricks/soft joints No provision for expansion
CONTEMPORARY MASONRY
Screen Wall Single wythe of brick with backup material Non load bearing Expansion joints
Screen Wall Assumes water will penetrate wall Provides for water intrusion Provides for water escape
COMMON ISSUES
Moisture penetrates walls Freeze thaw action
Moisture penetrates walls Surface spalling
Moisture trapped in walls Efflorescence- deposit of salts
Moisture trapped in walls Rising damp
Mortar harder than brick Brick erodes, mortar remains
Movement Vertical and horizontal displacement
PROPER TREATMENTS
Secretary of the Interior s Standards National Standards & Guidelines
Cleaning Sample test panel, mildest treatment Typically done before repointing or replacement
Cleaning Medium bristle brush and non-ionic detergent Rinse thoroughly
Cleaning Sand blasting not recommended
Repointing Carefully remove deteriorated mortar Replace only deteriorated mortar
Repointing Replace with mortar softer than the brick Match original mortar color and joint type
Repointing Match composition, color and joint type of original
Repointing Incorrect color mortar and wider joints
Brick replacement Very difficult to match new brick to old Difficult to match new mortar color to old
Brick replacement Restoration of façade with reclaimed and recycled brick
CONDITION ASSESSMENT & METHODOLOGY
Assessing an Existing Masonry Building Existing Condition Survey / Laser Scan Photographic Documentation Sounding Inner Wall Sampling Laboratory tests Chemical Analysis Petrographic Examination Brick Absorption Tests Brick & Prism Compression Test
EXISTING CONDITION SERVEY with a Laser Scanner Highly portable laser scanning equipment. Scanner and tripod Battery and computer 3D laser scanning technology provides a snap shot in time, an archive of information that does not change.
Laser Scan
Photographic Documentation
Sounding & Inner Wall Sampling Energy absorption vs. rebound Solid wall- ping sound Hollow wall - thud sound Deteriorated wall muted thud Visual survey of inner wall Are the bricks solid? Is the mortar solid? Are there gaps in mortar? Is the wall wet? Retrieve samples for lab test.
Laboratory Tests: Chemical Analysis of Masonry Mortar Finding the proper mortar match for repairs ASTM C 1324 is a combination of test procedures for microscopic examination and chemical analysis of mortar to determine components of masonry mortar and quantities of components. In other words, reverse engineering of mortar.
Laboratory Tests: Petrographic Examination & Absorption Tests A polarizing light microscope is used to view the sample and help analyze the mortar. Brick samples are heating and boiled to analyze their absorption rates
Laboratory Tests: Brick & Prism Compressive Strength Matching the existing brick strength is important to the future integrity of the entire wall. Similar to the brick compressive test, this test analyzes a portion of the masonry wall including the mortar.
PROJECT OVERVIEW
Significance Local significance industry/commerce Link to agricultural industry Coming of age of livestock feed industry 1931-1941 Best remaining example of pre WWII livestock
Character Defining Features Large main block flanked by set back wings Dominance of primary facade
Character Defining Features Repetitive segmented & corbeled semicircular arches Large window openings, banding, corbeled parapets
Character Defining Features Large interior space
History Constructed 1905-1906 as US Sugar Beet Co. Sold at auction May 1924 / fall 1929
History James Garver Feed & Storage 1975 Garver Feed & Supply Co.
History Madison Landmark 1994 Business closed October 1997.
Preservation Principles National Park Service Standards Cogent link to the past Stabilization
STRUCTURAL & ENVELOPE EXISTING CONDITION
Typical Building Envelope findings Rising damp Deteriorated sills Freeze thaw damage Gaps within mortar bed Failing roofing Non-weather tight openings Deteriorated parapets Spalling masonry Failing mortar
Rising damp Masonry wall acts like a sponge leading to faliiling mortar and spalled brick. (A) (B) Also note the distinctive tide mark. (B) (A)
Rising damp Failed roofing causes rising damp issues on the interior. Failing mortar & spalled brick.(a) Also note the distinctive tide mark. (B) (B) (A)
Deteriorated sills Typical sill condition Loose mortar (A) (A) (B) Fractured brick (B)
Freeze thaw damage First two interior brick courses experience freeze thaw. One full brick (2-2/3 ) concealed within solid ice. (A) (B) (A) Snow is 14 inches at deepest point.(b)
Freeze thaw damage Exposed window sill.(a) (B) (A) Exposed top of wall.(b)
Deteriorated parapets
Spalling masonry Fracturing concrete band.(a) (A) (B) Spalled brick.(b)
Failing mortar
Gaps within mortar bed
Failing roofing
Non-weather tight openings
Atypical Building Envelope findings Excessive water damage Vegetation within walls
Excessive water damage AREA F AREA H
Vegetation within walls
Typical Structural Findings Wood Roof Deterioration Concrete Roof Deterioration
Deteriorated Wood Framing Sheathing Joists Nailers Steel framing supporting the wood framing in most cases was found to be OK
Deteriorated Concrete Spalled sections of concrete Holes on Concrete Roof
Atypical Structural findings Detrimental Movements Structural Masonry Cracks Bad Lintels Stability Issues Unknown Conditions
Detrimental Movements Bowing Bulging Movement related to settlements Movement related to thermal changes
Structural Cracks Cracks at Lintels Wall Separation Cracks related to possible settlements
Bad Lintels Steel Masonry
Stability Issues Tall walls with openings Lack of connection to floor or roof structure
Unknown Conditions Significant amount of concealed and inaccessible areas What will we find during repairs, stabilization, and construction?
SUMMARIES OF STABILIZATION
Stabilization strategies for Structural Issues Roofs, Wood and Concrete Detrimental Movements Structural Masonry Cracks Bad Lintels Stability Issues, Diaphragms, Walls, Columns, Trusses Unknown Conditions D, F, G, H
Masonry walls EXTERIOR INTERIOR
COST ESTIMATE DEVELOPMENT
Estimating Process and Tools Scopes of Work Defined Detailed Quantity Surveys Unusual Conditions Identified Subcontractor Input Segregation by Building Area
Cost Evaluation and Considerations Historical Cost Database Subcontractor Input Unit Prices Established Total Project Cost
SUMMARY
Have a good understanding of the extent of deterioration and therefore probable costs All solvable stabilization issues Implementation could be phased to accommodate budget Stabilization should create opportunities for those interested in the adaptive reuse