Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs
---
title: Cast Stone
…99 unchanged lines
### Shop drawings shall locate every coordinable item against the contract drawings; unit setting locations and coursing references are indicated [[drawing: cast stone elevations]].
−### Color-and-texture samples shall be retained by the Architect as the contractual standard against which delivered units are judged. {note}
+### Color-and-texture samples shall be retained by the Architect as the contractual standard against which delivered units are judged.
### Cast stone color and texture vary measurably between batches and between plants because they depend on pigment dosage, aggregate source, and finishing technique. Without an approved physical sample, the Owner has no enforceable color standard and disputes over delivered color cannot be resolved on a contractual basis. {note}
…47 unchanged lines
## A Cast Stone Institute certified plant should be specified where third-party verification of production practice is required by the Owner.
−## A field sample panel of representative units, set with the specified mortar and joint treatment, should be erected and approved before bulk installation proceeds.
−
−## The approved color-and-texture sample shall govern acceptance; units differing visibly in color, texture, or finish from the approved sample shall be rejected.
−
−## Plant certification and independent testing are the two complementary quality controls for cast stone, and a robust specification uses both. {note}
−
−## Plant certification attests to the production process — that the plant has the equipment, procedures, and quality records to make compliant units consistently. Independent testing attests to the product — that representative units actually meet the strength, absorption, and freeze-thaw limits. Each addresses a failure mode the other does not, so both are specified rather than treating one as a substitute for the other. {note}
−
```datasheet
label: Plant certification requirement
…5 unchanged lines
```
−# Environmental and Service Conditions {toc}
+## A field sample panel of representative units, set with the specified mortar and joint treatment, should be erected and approved before bulk installation proceeds.
−## Units exposed to freeze-thaw cycling, de-icing salts, or marine environments shall be specified with air entrainment, absorption limits, and anchor materials appropriate to that exposure.
+## The approved color-and-texture sample shall govern acceptance; units differing visibly in color, texture, or finish from the approved sample shall be rejected.
−## Exposure conditions drive several mix and hardware decisions at once, and selecting the wrong exposure class is a durability error that surfaces only after years in service. {note}
+## Plant certification and independent testing are the two complementary quality controls for cast stone, and a robust specification uses both. {note}
−## A unit specified for a benign interior or sheltered exposure may use grey cement, standard absorption limits, and galvanized anchors. The same unit on a parapet coping in a freeze-thaw climate, or near de-icing salt or salt spray, needs entrained air, a tighter absorption limit, and stainless anchors. Because the visible unit looks identical in both cases, the exposure class must be stated explicitly so the producer proportions the mix and selects hardware correctly. {note}
+## Plant certification attests to the production process — that the plant has the equipment, procedures, and quality records to make compliant units consistently. Independent testing attests to the product — that representative units actually meet the strength, absorption, and freeze-thaw limits. Each addresses a failure mode the other does not, so both are specified rather than treating one as a substitute for the other. {note}
+# Environmental and Service Conditions {toc}
+
+## Units exposed to freeze-thaw cycling, de-icing salts, or marine environments shall be specified with air entrainment, absorption limits, and anchor materials appropriate to that exposure.
+
```datasheet
label: Exposure class
…7 unchanged lines
```
+## Exposure conditions drive several mix and hardware decisions at once, and selecting the wrong exposure class is a durability error that surfaces only after years in service. {note}
+
+## A unit specified for a benign interior or sheltered exposure may use grey cement, standard absorption limits, and galvanized anchors. The same unit on a parapet coping in a freeze-thaw climate, or near de-icing salt or salt spray, needs entrained air, a tighter absorption limit, and stainless anchors. Because the visible unit looks identical in both cases, the exposure class must be stated explicitly so the producer proportions the mix and selects hardware correctly. {note}
+
### Units in freeze-thaw exposure shall be air-entrained to 4 to 8 percent.
…26 unchanged lines
### Wet-cast units shall be produced where reinforcement cages, complex geometry, or fine profile detail are required.
−### Vibratory dry-tamp (VDT) units may be produced for simpler unreinforced units where a uniform fine-grained texture is acceptable.
−
−### The casting method is not a free interchange, and specifying a reinforced unit without specifying wet-cast is a common error that forces a non-compliant substitution. {note}
−
−### The vibratory dry-tamp process compacts a near-zero-slump mix and cannot encase a reinforcing cage, so it is limited to unreinforced units. Wet-cast uses a flowable mix that surrounds reinforcement and fills intricate forms. When a lintel or long cantilever coping that must be reinforced is specified without naming the casting method, the producer either cannot comply or quietly substitutes an unreinforced VDT unit in a structural location. Reinforced units therefore must be specified as wet-cast. {note}
−
```datasheet
label: Casting method
…6 unchanged lines
```
+### Vibratory dry-tamp (VDT) units may be produced for simpler unreinforced units where a uniform fine-grained texture is acceptable.
+
+### The casting method is not a free interchange, and specifying a reinforced unit without specifying wet-cast is a common error that forces a non-compliant substitution. {note}
+
+### The vibratory dry-tamp process compacts a near-zero-slump mix and cannot encase a reinforcing cage, so it is limited to unreinforced units. Wet-cast uses a flowable mix that surrounds reinforcement and fills intricate forms. When a lintel or long cantilever coping that must be reinforced is specified without naming the casting method, the producer either cannot comply or quietly substitutes an unreinforced VDT unit in a structural location. Reinforced units therefore must be specified as wet-cast. {note}
+
## Unit Construction {toc}
…6 unchanged lines
### In homogeneous units the entire cross-section uses the color mix, which is simple and is the usual choice for small trim. In facing-and-backup units the costly color and aggregate are placed only in the exposed face layer while a plain backup mix forms the body, cast at the same time so the layers bond monolithically. The two approaches produce the same visible face; the choice is an economic one that the unit size and quantity drive. {note}
+### The unit construction method shall be specified, selected based on unit size and quantity.
+
```datasheet
label: Unit construction
…36 unchanged lines
## Units shall attain a minimum compressive strength of 6,500 psi at 28 days when tested per ASTM C1194.
−## Reinforced lintels and units in high-traffic or high-load locations should be specified at a higher compressive strength where the structural demand warrants it.
−
−## The 6,500 psi minimum is the ASTM C1364 baseline and is sufficient for the great majority of trim units; higher strength is reserved for genuine structural demand. {note}
−
−## The C1364 minimum already exceeds typical masonry trim service loads, so specifying it satisfies most units without over-specification. A higher class (8,000 to 10,000 psi) is appropriate for reinforced lintels carrying real spans, for stair treads, or for units in high-traffic locations, where the added strength is doing work. Routinely raising the strength on every unit adds cost and tightens the mix unnecessarily. {note}
−
```datasheet
label: Minimum compressive strength at 28 days
…6 unchanged lines
```
−## Units shall exhibit cold-water absorption not exceeding 6 percent and boiling-water absorption not exceeding 10 percent when tested per ASTM C1195.
+## Reinforced lintels and units in high-traffic or high-load locations should be specified at a higher compressive strength where the structural demand warrants it.
−## A tighter cold-water absorption limit of 4 percent should be specified only for severe marine or de-icing-salt exposure.
+## The 6,500 psi minimum is the ASTM C1364 baseline and is sufficient for the great majority of trim units; higher strength is reserved for genuine structural demand. {note}
−## Absorption is the single best field indicator of cast stone durability, because a denser, less absorptive unit resists freeze-thaw and salt damage. {note}
+## The C1364 minimum already exceeds typical masonry trim service loads, so specifying it satisfies most units without over-specification. A higher class (8,000 to 10,000 psi) is appropriate for reinforced lintels carrying real spans, for stair treads, or for units in high-traffic locations, where the added strength is doing work. Routinely raising the strength on every unit adds cost and tightens the mix unnecessarily. {note}
−## Water that a unit absorbs is water available to freeze, expand, and spall the face, and to carry chlorides into the body. The 6 percent cold-water limit is the standard durability threshold and is correct for ordinary freeze-thaw exposure. Dropping to 4 percent meaningfully improves resistance in the harshest marine and de-icing-salt service, but it is harder to achieve and should not be imposed where the milder exposure does not need it. {note}
+## Units shall exhibit cold-water absorption not exceeding 6 percent and boiling-water absorption not exceeding 10 percent when tested per ASTM C1195.
```datasheet
…7 unchanged lines
```
+## A tighter cold-water absorption limit of 4 percent should be specified only for severe marine or de-icing-salt exposure.
+
+## Absorption is the single best field indicator of cast stone durability, because a denser, less absorptive unit resists freeze-thaw and salt damage. {note}
+
+## Water that a unit absorbs is water available to freeze, expand, and spall the face, and to carry chlorides into the body. The 6 percent cold-water limit is the standard durability threshold and is correct for ordinary freeze-thaw exposure. Dropping to 4 percent meaningfully improves resistance in the harshest marine and de-icing-salt service, but it is harder to achieve and should not be imposed where the milder exposure does not need it. {note}
+
## Linear drying shrinkage shall not exceed 0.065 percent.
…6 unchanged lines
## Unreinforced units shall be limited to spans not exceeding 4 feet; units spanning more than 4 feet shall be wet-cast and reinforced.
−## Lintels, long sills, and cantilever copings shall be wet-cast and reinforced regardless of nominal span.
−
−## Span and cantilever, not unit length alone, decide whether a unit must be reinforced. {note}
−
−## A short unit set in continuous bearing carries little bending and can be unreinforced. A unit that spans an opening, projects as a cantilever, or runs long between supports develops tensile stress on its underside that plain cast stone cannot reliably carry, so it must be wet-cast around a reinforcing cage. The 4 foot unreinforced limit is the conventional dividing line, with lintels and cantilevers always reinforced because their geometry guarantees bending. {note}
−
```datasheet
label: Reinforcement
…6 unchanged lines
```
−# Finish {toc}
+## Lintels, long sills, and cantilever copings shall be wet-cast and reinforced regardless of nominal span.
−## The unit finish shall match the approved color-and-texture sample.
+## Span and cantilever, not unit length alone, decide whether a unit must be reinforced. {note}
−## Finish is selected to imitate the target natural stone, and each finish exposes the aggregate differently. {note}
+## A short unit set in continuous bearing carries little bending and can be unreinforced. A unit that spans an opening, projects as a cantilever, or runs long between supports develops tensile stress on its underside that plain cast stone cannot reliably carry, so it must be wet-cast around a reinforcing cage. The 4 foot unreinforced limit is the conventional dividing line, with lintels and cantilevers always reinforced because their geometry guarantees bending. {note}
−## An as-cast smooth finish reads as a fine, sealed stone face. Acid-etching lightly opens the surface for a honed limestone look. Sandblasting, in light, medium, or heavy degrees, removes progressively more cement paste to expose aggregate and deepen texture. Tooled finishes cut linear or bush-hammered patterns. The choice is governed by the natural stone being matched and must be represented in the approved sample so delivered units can be judged against it. {note}
+# Finish {toc}
+## The unit finish shall match the approved color-and-texture sample.
+
```datasheet
label: Finish
…9 unchanged lines
```
+## Finish is selected to imitate the target natural stone, and each finish exposes the aggregate differently. {note}
+
+## An as-cast smooth finish reads as a fine, sealed stone face. Acid-etching lightly opens the surface for a honed limestone look. Sandblasting, in light, medium, or heavy degrees, removes progressively more cement paste to expose aggregate and deepen texture. Tooled finishes cut linear or bush-hammered patterns. The choice is governed by the natural stone being matched and must be represented in the approved sample so delivered units can be judged against it. {note}
+
# Unit Geometry and Drainage {toc}
…6 unchanged lines
## A flat-topped sill or coping ponds water, which then migrates through head joints into the wall below. A wash slope sheds that water to the face. A drip edge — a groove or kerf on the underside of the projection — breaks the surface tension that would otherwise carry runoff back along the soffit to the wall. Both features are cast into the unit and cost nothing to include, but are easily left off a profile and are then impossible to add in the field. {note}
−```datasheet
−label: Coping profile
−type: select
−options:
− - Single-slope
− - Saddle (double-slope)
− - Flat-top with drip edges
−default: Single-slope
−```
+## The coping width shall be specified, and the unit shall be cast with the wash slope and drip edge required for that width.
```datasheet
…10 unchanged lines
```
+```datasheet
+label: Coping profile
+type: select
+options:
+ - Single-slope
+ - Saddle (double-slope)
+ - Flat-top with drip edges
+default: Single-slope
+```
+
## Minimum unit thickness for exterior copings and projecting sills shall be 3-1/2 inches; non-structural decorative panels shall be not less than 2 inches thick.
## Maximum unit weight for unassisted field handling shall be coordinated with the installer; units exceeding the agreed limit shall be set with crane or mechanical lift assistance.
−## Unit weight must be a stated requirement, not an afterthought, because it governs both safety and placement quality. {note}
−
−## A long coping or reinforced lintel can readily exceed what two workers can safely set by hand, commonly in the range of 150 to 300 pounds. If the specification is silent on weight, oversized units arrive without lifting provisions, leading to dropped units, injuries, and pieces forced into place out of alignment. Stating a maximum unit weight for hand setting, and requiring mechanical lift above it, makes the handling method an explicit part of the design. {note}
−
```datasheet
label: Maximum unit weight for unassisted hand setting
…6 unchanged lines
```
+## Unit weight must be a stated requirement, not an afterthought, because it governs both safety and placement quality.
+
+## A long coping or reinforced lintel can readily exceed what two workers can safely set by hand, commonly in the range of 150 to 300 pounds. If the specification is silent on weight, oversized units arrive without lifting provisions, leading to dropped units, injuries, and pieces forced into place out of alignment. Stating a maximum unit weight for hand setting, and requiring mechanical lift above it, makes the handling method an explicit part of the design. {note}
+
# Anchorage {toc}
## Anchors, dowels, ties, and straps shall be Type 304 stainless steel as the default, hot-dip galvanized per ASTM A153 where permitted by exposure, or Type 316 stainless steel for marine and coastal exposure.
−## Galvanized anchors shall not be used in marine, coastal, or de-icing-salt exposure.
−
−## Anchor material is a long-life durability decision, and using galvanized hardware in a salt environment causes staining and spalling within the building's service life. {note}
−
−## Hot-dip galvanizing protects embedded steel adequately in ordinary exposure, but in marine air or where de-icing salts are present the zinc coating is consumed and the steel corrodes, expanding and cracking the surrounding cast stone and bleeding rust stains down the face within roughly 10 to 15 years. Stainless steel, Type 304 generally and Type 316 in chloride-laden environments, avoids this and is the default precisely because anchor replacement after installation is effectively impossible. {note}
−
```datasheet
label: Anchor and dowel material
…6 unchanged lines
```
+## Galvanized anchors shall not be used in marine, coastal, or de-icing-salt exposure.
+
+## Anchor material is a long-life durability decision, and using galvanized hardware in a salt environment causes staining and spalling within the building's service life. {note}
+
+## Hot-dip galvanizing protects embedded steel adequately in ordinary exposure, but in marine air or where de-icing salts are present the zinc coating is consumed and the steel corrodes, expanding and cracking the surrounding cast stone and bleeding rust stains down the face within roughly 10 to 15 years. Stainless steel, Type 304 generally and Type 316 in chloride-laden environments, avoids this and is the default precisely because anchor replacement after installation is effectively impossible. {note}
+
## Copings and projecting units shall be secured with stainless steel dowels of 3/8 inch or 1/2 inch diameter set into the supporting masonry.
…14 unchanged lines
## Setting mortar shall comply with ASTM C270, Type N for above-grade setting beds and joints.
−## Type S mortar may be used for below-grade or high-load bearing applications where the additional strength is required.
−
−## Type N is the correct default for cast stone, and a blanket Type S requirement is a durability mistake. {note}
−
−## Type S mortar is stronger and less permeable than Type N, and in many cast stone mixes it is also harder than the units it sets. A mortar harder than the stone concentrates movement and freeze-thaw stress at the unit face instead of relieving it in the softer joint, causing the cast stone — not the mortar — to spall. Type N is softer and more forgiving and is correct for the great majority of above-grade work; Type S is reserved for the specific below-grade and high-load cases that genuinely need it. {note}
−
```datasheet
label: Setting mortar type
…5 unchanged lines
```
+## Type S mortar may be used for below-grade or high-load bearing applications where the additional strength is required.
+
+## Type N is the correct default for cast stone, and a blanket Type S requirement is a durability mistake. {note}
+
+## Type S mortar is stronger and less permeable than Type N, and in many cast stone mixes it is also harder than the units it sets. A mortar harder than the stone concentrates movement and freeze-thaw stress at the unit face instead of relieving it in the softer joint, causing the cast stone — not the mortar — to spall. Type N is softer and more forgiving and is correct for the great majority of above-grade work; Type S is reserved for the specific below-grade and high-load cases that genuinely need it. {note}
+
## Mortar joints shall be 3/8 inch wide for masonry-coursed installations, or 1/4 inch where a tight joint is architecturally required.
…14 unchanged lines
### Sealant joints shall be used at relief and expansion locations and at junctions with dissimilar materials.
−### Identifying which joints stay open for drainage is as important as specifying the sealant, because a sealed weep path traps water in the wall. {note}
−
−### Behind copings and above flashing, certain head joints are deliberately left open to let water that reaches the flashing plane drain out. If the specification calls for sealant at all joints without exempting these drainage joints, the installer seals the weeps, water collects in the backup wall, and the failure shows up as efflorescence and freeze-thaw damage well away from its cause. The drawings must distinguish drainage joints from sealed joints; coordination with the weep system is governed by [[sync/through-wall-flashing]]. {note}
−
```datasheet
label: Joint treatment at relief and movement locations
…5 unchanged lines
```
+### Identifying which joints stay open for drainage is as important as specifying the sealant, because a sealed weep path traps water in the wall. {note}
+
+### Behind copings and above flashing, certain head joints are deliberately left open to let water that reaches the flashing plane drain out. If the specification calls for sealant at all joints without exempting these drainage joints, the installer seals the weeps, water collects in the backup wall, and the failure shows up as efflorescence and freeze-thaw damage well away from its cause. The drawings must distinguish drainage joints from sealed joints; coordination with the weep system is governed by [[sync/through-wall-flashing]]. {note}
+
## Movement Joints {toc}
…18 unchanged lines
## Cast stone coursing heights, sill heights, and lintel seat heights shall be coordinated with the backup masonry module before fabrication.
−## Coursing coordination must happen on paper before units are cast, because a mismatch discovered in the field is expensive to correct. {note}
+## Coursing coordination must happen on paper before units are cast, because a mismatch discovered in the field is expensive to correct.
## Cast stone sill heights, lintel seats, and band course elevations have to land on the backup wall's coursing module — the CMU or brick course heights set under [[sync/unit-masonry]] or [[sync/brick-masonry]]. If the trim is dimensioned independently and the modules do not align, the mismatch is found only when units arrive and will not seat at the coursing, forcing field shimming, cut units, or remanufacture. Reconciling the trim dimensions with the backup module during shop drawing review prevents this. {note}
…33 unchanged lines
## The Contractor shall deliver attic-stock spare units of selected profiles, from the same production run as the installed work, for future replacement.
−## Spare units should be furnished for the most exposed and most likely-to-be-damaged profiles, such as copings, sills, and base course units. {note}
−
−## Cast stone color and texture cannot be matched exactly in a later production run because aggregate lots, pigment dosage, and finishing crews change over time. Holding spares from the original run gives the Owner color-correct replacements for the units most likely to be struck or weathered. Coordination, quality, and submittal procedures common to this and other trades are governed by [[sync/submittal-and-quality-procedures]]. {note}
−
```datasheet
label: Spare unit profiles to stock
…10 unchanged lines
- Sills
```
+
+## Spare units should be furnished for the most exposed and most likely-to-be-damaged profiles, such as copings, sills, and base course units. {note}
+
+## Cast stone color and texture cannot be matched exactly in a later production run because aggregate lots, pigment dosage, and finishing crews change over time. Holding spares from the original run gives the Owner color-correct replacements for the units most likely to be struck or weathered. Coordination, quality, and submittal procedures common to this and other trades are governed by [[sync/submittal-and-quality-procedures]]. {note}