+---
+title: Hollow Metal Doors and Frames
+category: Architectural / Openings
+toc_depth: 3
+description: >
+ When to use: Steel-sheet hollow metal doors and frames for commercial, institutional,
+ industrial, and government openings — flush, seamless, and embossed faces over honeycomb,
+ polystyrene, polyurethane, temperature-rise, or acoustic cores; knocked-down, welded, and
+ slip-on frames; standard through maximum-duty grades (ANSI/SDI A250.8 Levels 1-4); interior
+ and exterior, fire-rated up to 3-hour, acoustic, galvanized, and galvannealed assemblies.
+ Not intended for: wood doors (see [[sync/wood-doors]]); locks, closers, exit devices, and
+ hinges (see [[sync/door-hardware]]); fire-rated vision glass and sidelites (see
+ [[sync/fire-rated-glazing]]); interior glazing partitions and relites not attached to a
+ hollow metal assembly (see [[sync/interior-glazing]]); bundled door-frame-hardware packages
+ (see [[sync/doors-frames-and-hardware]]); aluminum storefront and curtain wall; and
+ detention/security hollow metal beyond commercial grade (HMMA 863), noted here only as a
+ boundary.
+---
+
+# Scope {toc}
+
+## This standard covers hollow metal doors and frames fabricated from steel sheet for commercial, institutional, industrial, and government construction. {note}
+
+## It addresses flush, seamless, and embossed steel door faces over honeycomb, polystyrene, polyurethane, temperature-rise, or fiberglass-mineral-wool cores; knocked-down, welded, and slip-on frames; and the full range of duty grades defined by ANSI/SDI A250.8, Levels 1 through 4. Both interior and exterior applications are included, as are fire-rated assemblies with listings up to 3-hour labels, acoustic-rated assemblies, and galvanized and galvannealed substrates. In practice this covers nearly every commercial opening that is not wood or aluminum storefront. {note}
+
+## Steel doors and frames shall be furnished as complete, coordinated openings, with door, frame, anchorage, reinforcement, and hardware preparation engineered as a single assembly.
+
+## The assembly shall be furnished by a single manufacturer for each opening, so that the duty grade, fire label, and hardware reinforcement of door and frame are matched.
+
+## Two parallel North American standards bodies govern hollow metal, and both are legitimate. {note}
+
+## The Steel Door Institute (SDI) publishes the ANSI/SDI A250 series; the Hollow Metal Manufacturers Association (HMMA, a division of NAAMM) publishes the HMMA 800 series. The two systems are complementary, not competing — many commercial projects cite ANSI/SDI A250.8 as the primary product standard and use an HMMA guide spec as a section template. This standard adopts the SDI Level system as the practical basis for duty-grade verification and references HMMA documents where they govern installation and hardware location. A given project should hold to one nomenclature throughout to avoid requests for information. {note}
+
+## Wood doors, including veneered, solid-core, and composite stile-and-rail wood doors, are covered by [[sync/wood-doors]] and are not within this standard. {note}
+
+## Finish hardware — locks, latches, closers, exit devices, hinges, and electrified hardware itself — is covered by [[sync/door-hardware]]; this standard governs only the reinforcement and preparation for that hardware. {note}
+
+## Fire-rated vision-panel and sidelite glass is covered by [[sync/fire-rated-glazing]], and interior glazing partitions and relites not attached to a hollow metal assembly are covered by [[sync/interior-glazing]]. {note}
+
+## Projects that bundle doors, frames, and hardware into a single combined package use [[sync/doors-frames-and-hardware]], which coordinates all three; this standard is the hollow-metal-only specification. {note}
+
+## Projects that bundle doors, frames, and hardware into a single combined package should use [[sync/doors-frames-and-hardware]] rather than this standard.
+
+## Aluminum storefront doors, curtain wall, and non-fire-rated glass frames are outside this standard. {note}
+
+## Detention and security hollow metal beyond commercial grade — the heavy-gauge product line governed by ANSI/NAAMM HMMA 863 — is a distinct category and is noted here only as a scope boundary, not detailed. {note}
+
+# Referenced Standards {toc}
+
+## Doors, frames, materials, fabrication, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited or the Authority Having Jurisdiction has adopted a different edition; the edition in force at the time of use shall be verified before specifying.
+
+## Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+## The ANSI/NAAMM HMMA 860 guide specification was under revision ballot in the 2024-2025 cycle and may supersede HMMA 861; verify the current published edition before specifying. {note}
+
+| Standard | Title |
+|----------|-------|
+| ANSI/SDI A250.8 (SDI-100) | Recommended Specifications for Standard Steel Doors and Frames |
+| ANSI/SDI A250.4 | Test Procedure and Acceptance Criteria for Physical Endurance for Steel Door and Frame Sets |
+| ANSI/SDI A250.10 | Test Procedure and Acceptance Criteria for Prime Painted Steel Surfaces for Steel Doors and Frames |
+| ANSI/SDI A250.11 | Recommended Erection Instructions for Steel Frames |
+| ANSI/NAAMM HMMA 861 | Guide Specifications for Commercial Hollow Metal Doors and Frames |
+| ANSI/NAAMM HMMA 840 | Guide Specifications for Installation and Storage of Hollow Metal Doors and Frames |
+| ANSI/NAAMM HMMA 831 | Recommended Hardware Locations for Hollow Metal Doors and Frames |
+| ANSI/NAAMM HMMA 863 | Detention Security Hollow Metal Doors and Frames |
+| ASTM A653/A653M | Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process |
+| ASTM A1008/A1008M | Steel, Sheet, Cold-Rolled, Carbon, Structural, High-Strength Low-Alloy |
+| UL 10B | Fire Tests of Door Assemblies (Neutral Pressure) |
+| UL 10C | Positive Pressure Fire Tests of Door Assemblies |
+| NFPA 80 | Standard for Fire Doors and Other Opening Protectives |
+| NFPA 252 | Standard Methods of Fire Tests of Door Assemblies |
+| IBC Section 716 | International Building Code — Opening Protectives |
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following action submittals for review before fabrication:
+- Product data for each door type, frame type, core, and finish, including the manufacturer's certification of the ANSI/SDI A250.8 Level and Model for each opening.
+- Shop drawings showing each opening by mark number, with elevations, door and frame profiles, throat dimensions, anchorage, reinforcement, hardware preparation locations, and vision-lite and louver cutouts.
+- A door and frame schedule keyed to the opening (door) schedule, listing duty grade, fire rating, core, substrate, finish, and handing for every opening.
+- Fire-rating label data and the listing report for each rated opening, identifying the test standard (UL 10C or UL 10B) and the maximum permitted vision-lite size.
+- Samples of factory finish color and, when requested, a corner sample of door and frame construction.
+
+```datasheet
+label: Action submittals required
+type: checkbox
+options:
+ - Product data (type, core, finish, certified Level/Model)
+ - Shop drawings (elevations, profiles, anchorage, reinforcement)
+ - Door and frame schedule keyed to opening schedule
+ - Fire-label listing report (test standard + max lite size)
+ - Finish samples / corner construction sample
+default:
+ - Product data (type, core, finish, certified Level/Model)
+ - Shop drawings (elevations, profiles, anchorage, reinforcement)
+ - Door and frame schedule keyed to opening schedule
+ - Fire-label listing report (test standard + max lite size)
+```
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following informational submittals:
+- Manufacturer's product certification that doors and frames comply with the specified ANSI/SDI A250.8 Level, including reference to the supporting ANSI/SDI A250.4 physical-endurance test.
+- Welder qualifications and welding procedures when shop-welded frames are specified.
+- The manufacturer's installation and storage instructions per ANSI/NAAMM HMMA 840.
+
+```datasheet
+label: Informational submittals required
+type: checkbox
+options:
+ - ANSI/SDI A250.8 Level certification (A250.4 endurance basis)
+ - Welder qualifications and procedures (welded frames)
+ - Manufacturer installation and storage instructions
+default:
+ - ANSI/SDI A250.8 Level certification (A250.4 endurance basis)
+ - Manufacturer installation and storage instructions
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the following closeout submittals:
+- Completed NFPA 80 field inspection and acceptance records for every fire-rated opening.
+- Operation and maintenance data, including touch-up paint matching the factory finish.
+- The manufacturer's written warranty.
+
+```datasheet
+label: Closeout submittals required
+type: checkbox
+options:
+ - NFPA 80 field inspection / acceptance records (rated openings)
+ - O&M data with touch-up paint
+ - Written warranty
+default:
+ - NFPA 80 field inspection / acceptance records (rated openings)
+ - O&M data with touch-up paint
+ - Written warranty
+```
+
+# Quality Assurance {toc}
+
+## The manufacturer shall be a current member of the Steel Door Institute or the Hollow Metal Manufacturers Association and shall be regularly engaged in producing hollow metal doors and frames of the type specified.
+
+## Doors and frames shall be fabricated by a single source so that components of each opening are mutually compatible in gauge, reinforcement, and label.
+
+## Fire-rated assemblies shall be labeled by a nationally recognized testing laboratory and shall bear a permanent label identifying the rating and the test standard. {note}
+
+## The label is the only field-verifiable evidence that the assembly was tested as a unit. Any field modification that is not within the listing — drilling for unlisted hardware, enlarging a lite, or cutting the door height beyond the listed allowance — voids the label and requires re-listing or replacement of the opening. {note}
+
+### Each fire-rated door and frame shall bear a permanent label from a nationally recognized testing laboratory stating the fire-protection rating.
+
+### Field modification of labeled assemblies beyond the limits of the listing is prohibited.
+
+## Duty grade selected for the opening governs the certified Level, which is validated by physical-endurance testing. {note}
+
+## ANSI/SDI A250.8 defines four Levels, and ANSI/SDI A250.4 prescribes the physical-abuse and cycle-endurance test that substantiates a Level claim. Specifying a Level without requiring the A250.4 basis invites under-built submittals that nominally cite the Level but were never tested to it. {note}
+
+```datasheet
+label: Door duty grade (ANSI/SDI A250.8 Level)
+type: radio
+options:
+ - Level 1 — Standard duty (limited traffic, light abuse)
+ - Level 2 — Heavy duty (general commercial traffic)
+ - Level 3 — Extra heavy duty (high traffic, schools, healthcare)
+ - Level 4 — Maximum duty (high abuse, industrial, public)
+default: Level 2 — Heavy duty (general commercial traffic)
+```
+
+# Environmental and Service Conditions {toc}
+
+## The steel substrate and coating shall be selected for the service environment of each opening, not assumed uniform across the project. {note}
+
+## Interior dry openings can use cold-rolled steel; interior humid or wet areas and any painted frame benefit from galvannealed steel, which holds paint better and resists corrosion at cut edges; exterior and corrosive-environment openings require hot-dip galvanized steel. Choosing a single substrate for the whole project either over-spends on interior doors or under-protects exterior ones. {note}
+
+## Exterior and high-humidity openings shall use hot-dip galvanized steel sheet conforming to ASTM A653, with a minimum coating designation of G90.
+
+## Interior painted frames and doors in humid areas should use galvannealed (A40) steel conforming to ASTM A653 to improve paint adhesion and edge corrosion resistance.
+
+## Interior doors and frames in dry, conditioned spaces may use cold-rolled steel conforming to ASTM A1008.
+
+```datasheet
+label: Steel substrate and coating
+type: radio
+options:
+ - Cold-rolled A1008 (interior, dry, conditioned)
+ - Galvannealed A653 A40 (interior humid / painted)
+ - Galvanized A653 G60 (exterior, sheltered)
+ - Galvanized A653 G90 (exterior, exposed / corrosive)
+default: Galvannealed A653 A40 (interior humid / painted)
+```
+
+## Thermal performance shall be specified for exterior openings in heating-dominated climates. {note}
+
+## A standard honeycomb-core door provides little thermal resistance. Polystyrene and polyurethane cores raise the assembly U-factor into the 0.35-0.59 BTU/hr·ft²·°F range and are appropriate for exterior openings in climate zones 4 and colder. If a core type is not called out, the fabricator will default to the least costly honeycomb core, and the thermal or acoustic intent is silently lost. {note}
+
+### Exterior doors in climate zone 4 and colder shall be furnished with an insulating core (polystyrene or polyurethane) meeting the project's specified maximum U-factor.
+
+```datasheet
+label: Exterior door thermal performance (maximum U-factor)
+type: range
+unit: BTU/hr·ft²·°F
+min: 0.30
+max: 0.60
+step: 0.01
+default: 0.50
+drawing_ref: true
+```
+
+# Materials and Substrate {toc}
+
+## Face-sheet thickness shall be specified as a minimum decimal thickness, not as a gauge number. {note}
+
+## Gauge designations are nominal and vary between manufacturers; a "18-gauge" sheet from one mill may be thinner than another's. ANSI/SDI A250.8 and the HMMA standards now express requirements as minimum decimal inch thickness for exactly this reason. Specifying by gauge alone allows an under-thickness substitution to pass review. {note}
+
+### Door face sheets shall be specified by minimum decimal thickness in conformance with ANSI/SDI A250.8 for the selected Level.
+
+### Frame material shall be specified by minimum decimal thickness in conformance with ANSI/SDI A250.8 for the selected Level.
+
+```datasheet
+label: Door face-sheet minimum thickness
+type: select
+options:
+ - 0.032 in (20 ga equivalent) — Level 1
+ - 0.042 in (18 ga equivalent) — Level 2
+ - 0.053 in (16 ga equivalent) — Level 3
+ - 0.067 in (14 ga equivalent) — Level 4
+default: 0.042 in (18 ga equivalent) — Level 2
+```
+
+```datasheet
+label: Frame minimum thickness
+type: select
+options:
+ - 0.053 in (16 ga equivalent) — standard interior
+ - 0.067 in (14 ga equivalent) — exterior / high-abuse
+ - 0.093 in (12 ga equivalent) — maximum-duty / masonry
+default: 0.053 in (16 ga equivalent) — standard interior
+```
+
+## Steel sheet shall be free of scale, pitting, coil breaks, and surface defects that would telegraph through the finish.
+
+## Stainless steel hollow metal, when specified for hygienic or coastal applications, shall use Type 304 or Type 316 face sheets over a steel subframe in conformance with the applicable HMMA stainless guide. {note}
+
+## Stainless face sheets are used for hospitals, food service, and exposed coastal exteriors where galvanized steel is insufficient. Type 316 is specified where chloride exposure is severe. {note}
+
+```datasheet
+label: Door face material
+type: radio
+options:
+ - Carbon steel (standard)
+ - Stainless steel Type 304 (hygienic interior)
+ - Stainless steel Type 316 (coastal / chloride exposure)
+default: Carbon steel (standard)
+```
+
+# Door Construction {toc}
+
+## Doors shall be 1-3/4 in (44 mm) nominal thickness unless an acoustic, security, or other assembly requires a different thickness. {note}
+
+## The 1-3/4 in door is the commercial standard for the overwhelming majority of openings. The 1-3/8 in door is a light residential or closet leaf rarely seen in commercial work; 2 in doors appear in acoustic and high-security assemblies. Selecting a non-standard thickness drives custom frame profiles and longer lead times, so it should be a deliberate choice. {note}
+
+### Doors shall be 1-3/4 in (44 mm) nominal thickness unless otherwise specified for an acoustic or security assembly.
+
+```datasheet
+label: Door nominal thickness
+type: radio
+options:
+ - 1-3/8 in (35 mm) — light / closet (rare in commercial)
+ - 1-3/4 in (44 mm) — standard commercial
+ - 2 in (51 mm) — acoustic / high-security
+default: 1-3/4 in (44 mm) — standard commercial
+```
+
+## Door face configuration (Model) is primarily aesthetic but affects sound attenuation and is specified by SDI Model. {note}
+
+## ANSI/SDI A250.8 defines three Models. Model 1 is full flush, a smooth face with no visible seam. Model 2 is seamless or center-seam, with the face sheets joined at a concealed seam for improved appearance. Model 3 is a stile-and-rail or embossed panel door, with pressed-in profiles that simulate a wood-panel door and is common in schools and public buildings. {note}
+
+```datasheet
+label: Door model (ANSI/SDI A250.8)
+type: radio
+options:
+ - Model 1 — Full flush
+ - Model 2 — Seamless / center seam
+ - Model 3 — Embossed / stile-and-rail panel
+default: Model 1 — Full flush
+```
+
+## Door face sheets shall be joined to vertical edge channels and to the core to form a torsionally rigid, flush leaf.
+
+## Vertical edges of doors shall be continuously welded, ground, and finished smooth, or mechanically interlocked, in conformance with the selected Model and Level.
+
+## Top and bottom of the door shall be closed with a continuous steel channel or closure flush with the face.
+
+## Exterior doors shall have a flush top closure to shed water.
+
+## Core type shall be specified explicitly for every door, since it governs thermal, acoustic, and fire behavior. {note}
+
+## Honeycomb kraft-paper core is the standard interior filler. Polystyrene and polyurethane cores add thermal resistance, and polyurethane also adds structural stiffness. Temperature-rise cores limit the heat transmitted through a stairwell door during a fire. Fiberglass and mineral-wool cores provide acoustic mass. Because the fabricator defaults to honeycomb when no core is named, omitting the core selection is a common and costly error. {note}
+
+```datasheet
+label: Door core
+type: radio
+options:
+ - Honeycomb kraft paper (standard interior)
+ - Polystyrene (thermal)
+ - Polyurethane (thermal + structural)
+ - Temperature-rise rated (stairwell / corridor)
+ - Fiberglass / mineral wool (acoustic)
+default: Honeycomb kraft paper (standard interior)
+```
+
+## Vision lites and louvers shall be located and sized on the shop drawings and shall not exceed the maximum permitted by the assembly's fire listing. {note}
+
+## For rated openings, the UL listing caps the maximum lite area and dictates the glazing product. An oversized lite voids the label. Louvers are generally not permitted in fire-rated doors except where specifically listed. Glass for rated lites is specified in [[sync/fire-rated-glazing]]. {note}
+
+### Vision-lite and louver cutouts in fire-rated doors shall not exceed the maximum size and locations permitted by the assembly listing.
+
+### Vision-lite glazing for rated openings shall be the fire-rated product required by the listing and shall be coordinated with [[sync/fire-rated-glazing]].
+
+```datasheet
+label: Vision lite
+type: radio
+options:
+ - None
+ - Narrow lite
+ - Half glass
+ - Full glass (vision panel)
+default: None
+drawing_ref: "door schedule / elevations"
+```
+
+# Frame Construction {toc}
+
+## Frame type shall be matched to the wall construction, since anchorage and assembly method differ by substrate. {note}
+
+## A knocked-down (KD) three-piece frame is field-assembled and is the common choice for new drywall partitions. A shop-welded one-piece frame, with corners welded, ground, and filled, is specified for masonry, concrete, and high-abuse openings. A slip-on drywall frame is applied over finished drywall without rough-in and suits retrofit and light commercial work. Selecting a slip-on or KD frame for a masonry opening, or vice versa, produces anchorage that does not suit the wall. {note}
+
+```datasheet
+label: Frame type
+type: radio
+options:
+ - Knocked-down (KD), three-piece field-assembled
+ - Shop-welded one-piece
+ - Slip-on drywall frame
+default: Knocked-down (KD), three-piece field-assembled
+```
+
+## Welded frames shall have corners mitered or coped, continuously welded on the contact surfaces, ground smooth, and filled so that no joint is visible after finishing.
+
+## Frame throat dimension shall be verified against the actual wall assembly thickness, including finishes, before fabrication. {note}
+
+## The throat is the dimension across the back of the frame that straddles the wall. A nominal 4-7/8 in frame profile will not fit a 6 in CMU wall, and a single project commonly has several wall thicknesses; verify each condition separately. {note}
+
+### Frame throat dimension shall match the wall assembly thickness shown on the wall sections, including all applied finishes.
+
+```datasheet
+label: Frame throat dimension
+type: select
+options:
+ - 4-7/8 in (124 mm) — standard 4-7/8 stud/drywall
+ - 5-3/4 in (146 mm)
+ - 6-3/4 in (171 mm)
+ - 8-3/4 in (222 mm) — 8 in CMU
+default: 4-7/8 in (124 mm) — standard 4-7/8 stud/drywall
+drawing_ref: "wall sections"
+```
+
+## Frame anchors shall be of the type and spacing appropriate to the substrate.
+
+## Frame anchors shall be furnished by the frame manufacturer.
+
+### Frames set in masonry shall be furnished with adjustable masonry T-anchors at the spacing required by ANSI/NAAMM HMMA 840.
+
+### Frames set in steel-stud drywall partitions shall be furnished with stud anchors engaging the studs at each jamb anchor location.
+
+### Floor anchors shall be provided at the base of each jamb and secured to the floor slab.
+
+```datasheet
+label: Frame anchor type
+type: radio
+options:
+ - Masonry T-anchor (CMU / brick)
+ - Stud anchor (steel-stud drywall)
+ - Existing-wall / compression anchor (retrofit)
+ - Welded-in (concrete / steel)
+default: Stud anchor (steel-stud drywall)
+drawing_ref: "wall type schedule"
+```
+
+## Frames installed in masonry shall be grouted solid at hinge and strike locations, at minimum, to resist deflection under hardware and lateral loads. {note}
+
+## An un-grouted masonry frame deflects under wall load and door operation, causing the door to bind and the latch to misalign. HMMA 840 requires grout fill at least at the reinforced hardware locations. A high-water structural grout can bow the frame faces. {note}
+
+### Hollow metal frames set in masonry shall be grouted solid at hinge and strike reinforcement locations as a minimum.
+
+### Grout for masonry frame fill shall be a low-slump mortar mix; high-water structural grout mixes that can bow the frame faces are not permitted.
+
+# Hardware Preparation and Reinforcement {toc}
+
+## Doors and frames shall be reinforced, drilled, and tapped at the factory for the hardware in the approved hardware schedule, at the locations of ANSI/NAAMM HMMA 831. {note}
+
+## Factory preparation keeps labeled assemblies within their listing. Accepting standard hardware locations blindly leads to field modification of labeled frames, which then require re-inspection. A closer or exit device imposes far higher loads than a passage latch. {note}
+
+### The manufacturer's standard hardware locations shall be verified against the actual hardware schedule from [[sync/door-hardware]] before fabrication.
+
+### Hardware reinforcement gauge shall be appropriate for the specific device in the approved hardware schedule.
+
+### Doors and frames shall be reinforced for hardware at the locations established by ANSI/NAAMM HMMA 831 unless the approved hardware schedule directs otherwise.
+
+### Hinge reinforcement shall be a minimum 7-gauge (0.179 in) backing plate for standard commercial doors and frames.
+
+### Closer, exit-device, and lock reinforcement shall be sized for the specific device in the approved hardware schedule and shall be welded in place.
+
+### Hardware preparation shall be coordinated with the hardware schedule of [[sync/door-hardware]] before fabrication.
+
+## Electrified hardware rough-in shall be provided in the hollow metal at the factory, never created by field drilling of a finished or labeled assembly. {note}
+
+## Electric strikes, maglocks, electrified hinges, and access-control devices require conduit knockouts, raceways, junction boxes, and through-bolt preparation built into the door and frame. Drilling these in the field after delivery — especially into a labeled assembly — voids the UL listing and damages the finish. {note}
+
+### Electrified hardware rough-in shall be carried in the hollow metal section and coordinated with the electrified hardware scope of [[sync/door-hardware]].
+
+### Doors and frames receiving electrified hardware shall be furnished with factory conduit knockouts, raceways, junction boxes, and through-bolt reinforcement for the scheduled devices.
+
+### Field drilling of labeled assemblies for electrified hardware is prohibited.
+
+```datasheet
+label: Electrified hardware rough-in
+type: checkbox
+options:
+ - Electric strike preparation
+ - Electrified hinge raceway and junction box
+ - Maglock through-bolt reinforcement
+ - Conduit knockouts for access-control wiring
+ - Power transfer (door-to-frame) preparation
+default: []
+drawing_ref: "hardware schedule / electrified opening list"
+```
+
+# Fire-Rated Assemblies {toc}
+
+## Fire-protection ratings shall be provided where the International Building Code requires opening protectives, and the required rating follows the rating of the wall. {note}
+
+## IBC Section 716 prescribes the opening-protective rating for each rated wall or partition. Ratings range from a 20-minute corridor protective, through 45-, 60-, and 90-minute labels, to the 3-hour label required at a fire wall — a rating only hollow metal achieves. A 20-minute assembly is not the same as a fully listed fire door: under NFPA 80 it has different hardware and glazing allowances; treat each rating class as a distinct assembly type. {note}
+
+```datasheet
+label: Fire-protection rating (IBC Section 716)
+type: radio
+options:
+ - Non-rated
+ - 20-minute (corridor / smoke)
+ - 45-minute (1-hour fire barrier)
+ - 60-minute (1-hour)
+ - 90-minute (2-hour fire barrier / exit enclosure)
+ - 3-hour (fire wall)
+default: Non-rated
+drawing_ref: "life-safety plan"
+```
+
+## Fire-rated door assemblies shall be tested and labeled to UL 10C positive-pressure criteria where required by the IBC. {note}
+
+## IBC Section 716 requires positive-pressure testing (UL 10C, equivalent to NFPA 252 under positive pressure) for fire doors in corridors and exit stairwells, which is effectively all rated hollow metal in commercial work. The legacy UL 10B neutral-pressure protocol remains valid only for the limited assemblies the code still permits. Positive-pressure listings typically require an intumescent edge seal as part of the listed assembly. {note}
+
+### Fire-rated door assemblies in corridors and exit enclosures shall carry a UL 10C positive-pressure label.
+
+```datasheet
+label: Fire test pressure protocol
+type: radio
+options:
+ - UL 10C — Positive pressure (corridors, stairwells; default)
+ - UL 10B — Neutral pressure (where code permits)
+default: UL 10C — Positive pressure (corridors, stairwells; default)
+```
+
+## Doors in exit stairwell enclosures shall be temperature-rise rated as required by IBC Section 716. {note}
+
+## A standard fire-rated door limits flame and smoke passage but does not limit the temperature of its unexposed face. IBC Section 716 requires exit-enclosure doors to be temperature-rise rated so occupants can pass a door with fire on the far side. The general limit is a maximum 450°F rise at 30 minutes; high-rise buildings require the more stringent 250°F limit. A standard fire label does not include this property, so it must be called out separately. {note}
+
+### Exit-enclosure (stairwell) doors shall carry a temperature-rise label not exceeding 450°F rise at 30 minutes, or 250°F where required for high-rise buildings.
+
+```datasheet
+label: Temperature-rise rating (stairwell / exit-enclosure doors)
+type: radio
+options:
+ - Not required (non-stairwell opening)
+ - 450°F max rise at 30 min (standard exit enclosure)
+ - 250°F max rise at 30 min (high-rise exit enclosure)
+default: Not required (non-stairwell opening)
+```
+
+## Fire-rated openings shall comply with NFPA 80 for clearances, hardware, glazing, and field acceptance.
+
+### Clearance at the head and jambs of single fire-rated doors, and at the meeting edges of pairs, shall not exceed 1/8 in (3.2 mm) per NFPA 80.
+
+### Clearance at the bottom of a fire-rated door without a threshold shall not exceed 3/4 in (19 mm) per NFPA 80.
+
+# Acoustic Assemblies {toc}
+
+## Sound-rated openings shall be furnished as a complete listed assembly — door, gasketed frame, and seals — because the rating is a property of the assembly, not the door alone. {note}
+
+## A bare flush door carries an STC of roughly 28 to 32. An acoustic assembly reaches STC 38 to 42 with a continuous gasketed frame, automatic drop seal, and a mineral-wool or dense core; high-acoustic specialty assemblies reach STC 44 to 48. Specifying an "STC-rated door" without the gasketing and seals delivers none of the rated performance. {note}
+
+### Acoustic openings shall be furnished as a complete laboratory-tested assembly including the door, gasketed frame, perimeter seals, and automatic drop seal required to achieve the specified STC.
+
+```datasheet
+label: Acoustic rating (STC)
+type: radio
+options:
+ - Not rated (standard flush, STC 28-32)
+ - STC 38 (acoustic assembly)
+ - STC 42 (acoustic assembly)
+ - STC 48 (high-acoustic specialty assembly)
+default: Not rated (standard flush, STC 28-32)
+```
+
+# Openings, Sizes, and Configuration {toc}
+
+## Standard door sizes shall be used wherever possible, and oversized leaves shall be flagged as custom. {note}
+
+## A 3 ft 0 in (914 mm) wide single leaf at 7 ft 0 in (2134 mm) height is the commercial 80% case. Heights of 8 ft 0 in (2438 mm) are common; anything taller than 9 ft or wider than 4 ft triggers custom fabrication and engineering review, with longer lead times and reinforcement implications. Pairs run 5 ft 0 in to 6 ft 0 in overall. Treating an oversized opening as standard leads to schedule and structural surprises. {note}
+
+### Doors wider than 4 ft 0 in (1219 mm) or taller than 9 ft 0 in (2743 mm) shall be furnished as engineered custom assemblies with reinforcement reviewed for the size.
+
+```datasheet
+label: Door width (single leaf)
+type: select
+options:
+ - 2 ft 6 in (762 mm)
+ - 2 ft 8 in (813 mm)
+ - 3 ft 0 in (914 mm) — standard egress
+ - 3 ft 6 in (1067 mm)
+ - 4 ft 0 in (1219 mm) — max standard
+default: 3 ft 0 in (914 mm) — standard egress
+drawing_ref: "door schedule"
+```
+
+```datasheet
+label: Door height
+type: select
+options:
+ - 6 ft 8 in (2032 mm)
+ - 7 ft 0 in (2134 mm) — standard
+ - 8 ft 0 in (2438 mm)
+ - 9 ft 0 in (2743 mm)
+ - 10 ft 0 in (3048 mm) — custom
+default: 7 ft 0 in (2134 mm) — standard
+drawing_ref: "door schedule"
+```
+
+```datasheet
+label: Opening configuration
+type: radio
+options:
+ - Single leaf
+ - Pair (equal leaves)
+ - Pair with active / inactive leaf
+ - Double egress
+default: Single leaf
+drawing_ref: "door schedule"
+```
+
+# Finish {toc}
+
+## Doors and frames shall receive a factory finish appropriate to the substrate and the field finishing intent. {note}
+
+## Most commercial hollow metal ships factory-primed for field painting. Where a durable factory finish is wanted, a powder coat or baked enamel is applied. Galvanized exterior assemblies may be primed over the coating or left for a galvanized-compatible field system. The prime coat itself is a tested product, not just paint. {note}
+
+### Factory prime coat shall conform to ANSI/SDI A250.10, applied over a chemically treated surface at a minimum 0.5 mil dry film thickness.
+
+### Where a factory finish coat is specified, it shall be a powder coat or baked enamel applied over the prepared and primed surface.
+
+```datasheet
+label: Factory finish
+type: radio
+options:
+ - Factory prime for field paint (ANSI/SDI A250.10)
+ - Factory powder coat
+ - Factory baked enamel
+ - Galvanized, primed
+default: Factory prime for field paint (ANSI/SDI A250.10)
+```
+
+# Testing {toc}
+
+## Manufacturer's physical-endurance testing shall substantiate the specified duty Level. {note}
+
+## ANSI/SDI A250.4 is the abuse and cycle-endurance test that backs a Level claim. The certification submitted under Quality Assurance is the project's evidence that the furnished product was actually tested to the Level specified, not merely cataloged at it. {note}
+
+### The manufacturer shall certify that the furnished doors and frames have passed ANSI/SDI A250.4 physical-endurance testing for the specified Level.
+
+## Completed fire-rated openings shall be field-inspected and documented per NFPA 80. {note}
+
+## NFPA 80 requires acceptance inspection of installed fire-door assemblies, and Authorities Having Jurisdiction increasingly require the inspection records as a condition of the certificate of occupancy. NFPA 80 also establishes the annual inspection regime that the owner must maintain over the life of the building. {note}
+
+### Each fire-rated opening shall be field-inspected for compliance with NFPA 80 after installation, and the inspection record shall be submitted.
+
+### The Contractor shall provide the owner with the NFPA 80 annual-inspection requirements and the baseline acceptance record for each rated opening.
+
+# Installation {toc}
+
+## Installation shall conform to ANSI/NAAMM HMMA 840 and ANSI/SDI A250.11, and to the manufacturer's instructions.
+
+### Frames shall be set plumb, square, level, and in alignment.
+
+### Frames shall be braced until permanently anchored.
+
+### Frames shall be anchored to the substrate with the anchor type and spacing specified for the wall condition before the wall is closed in.
+
+### Doors shall be hung to operate freely and shall swing a full 90° with all hardware engaged, in conformance with ANSI/NAAMM HMMA 840 acceptance.
+
+### Clearances of installed doors shall be within the tolerances of ANSI/NAAMM HMMA 840, and within NFPA 80 limits for fire-rated openings.
+
+## Field modifications that would void a fire label, including cutting, drilling, or welding outside the listing, are prohibited. {note}
+
+## Installed openings shall be adjusted so the door latches and operates without binding, sticking, or excessive force. {note}
+
+## HMMA 840 Section 7 sets the operational acceptance: a properly installed door swings freely through its full arc with hardware engaged. Binding usually traces back to an out-of-plumb or un-grouted frame. {note}
+
+### Binding caused by an out-of-plumb or un-grouted frame shall be corrected at the frame and not masked by hardware adjustment.
+
+### Each installed door shall be adjusted to swing freely, latch positively, and operate without binding.
+
+# Delivery, Storage, and Handling {toc}
+
+## Doors and frames shall be delivered, stored, and handled per ANSI/NAAMM HMMA 840 to protect the finish and prevent rust and distortion. {note}
+
+## Hollow metal is easily dented and prone to surface rust if stored in standing water or stacked flat where moisture is trapped. HMMA 840 requires upright storage, off the ground, under cover, with spacers between units for air circulation. {note}
+
+### Doors shall be stored upright, off the ground on blocking, under cover, with spacers between units to allow air circulation.
+
+### Frames shall be stored to prevent rust, distortion, and finish damage, and shall not be stacked in a manner that bends the profiles.
+
+### Damaged or rusted units shall be repaired to the original finish quality or replaced, at the manufacturer's direction, and units with structural damage shall be replaced.
+
+# Warranty {toc}
+
+## The manufacturer shall warrant the doors and frames against defects in materials and workmanship for the project's specified warranty period. {note}
+
+## The warranty covers fabrication and material defects — delamination, weld failure, core separation, and premature corrosion of properly maintained units. It does not cover damage from field modification, abuse, or failure to maintain the finish. {note}
+
+### The manufacturer shall warrant doors and frames against defects in materials and workmanship for not less than the specified warranty period from Substantial Completion.
+
+```datasheet
+label: Warranty period
+type: radio
+options:
+ - 1 year
+ - 2 years
+ - 5 years
+default: 1 year
+```
+
+# Spare Parts {toc}
+
+## Touch-up materials and selected spare units should be provided so the owner can maintain the openings without re-procurement. {note}
+
+## Touch-up paint matched to the factory finish lets the owner address minor field damage immediately, before rust starts. On larger projects, a small stock of spare frames or doors of the most common opening type shortens replacement time after damage. {note}
+
+### The Contractor shall deliver touch-up paint matching each factory finish furnished on the project.
+
+```datasheet
+label: Spare units (optional, per project)
+type: checkbox
+options:
+ - Touch-up paint (each factory finish)
+ - Spare standard interior door leaf
+ - Spare standard frame
+default:
+ - Touch-up paint (each factory finish)
+```