tp_dlg.dcl — Top Plate Configuration

File: tp_dlg.dcl
Version: v3.60
Category: Dialog Definitions
Size: 8.4 KB (254 lines)

Note

Roof Connection Feature

Configure top plate connections for roof system attachment. Critical for transferring roof loads to panels and preventing uplift.

Functional Purpose

Top Plate Connections - Configures connection hardware at panel top edge for roof system attachment (metal deck, wood rafters, concrete roof panels).

Key Functions:

  1. Specifies plate types (metal flush, concrete bearing, wood pocket)

  2. Sets plate dimensions (width, length, thickness)

  3. Controls spacing (single or array pattern)

  4. Defines edge distance (from panel edges)

  5. Manages elevation (flush to top or recessed)

User Need

Roof connection plates for:

  • Metal roof deck attachment (most common)

  • Wood rafter connections (residential/light commercial)

  • Concrete roof panel bearing (parking structures)

  • Parapet cap connections (architectural)

  • Roof truss bearing points

Typical Workflow

1. User clicks [Top Plate] in mp_dlg
2. tp_dlg opens
3. User selects type: "Metal plate flush"
4. User sets dimensions: 4" wide × 6" long × 1/2" thick
5. User enables array: 4'-0" spacing across panel width
6. System warns: "Metal plates flush to top - verify elevations"
7. User clicks OK
8. 6 metal plates spaced 4' apart drawn at panel top

Control Semantics

Primary Controls

Plate Type:

  • tpt - Top plate type dropdown:

    • Metal plate flush (cast flush to concrete top) - Most common

    • Concrete bearing plate (raised bearing strip)

    • Wood plate pocket (recess for wood blocking)

    • Embed anchor (threaded inserts for bolting)

    • Custom connection

Dimensions:

  • tpw - Plate width (perpendicular to panel edge): 3”-6” typical

  • tpl - Plate length (along panel edge): 4”-12” typical

  • tpthk - Plate thickness: 1/4”, 3/8”, 1/2”, 5/8”

Spacing:

  • tps - Plate spacing (if array): 2’-0” to 8’-0” on center

  • tpe - Edge distance (from panel sides): 6” minimum

  • tpa - Array enable (multiple plates vs single)

Special:

  • tpf - Flush to top flag (critical for metal plates)

  • tpr - Recess depth (if pocketed): 0” to 2”

Metal Plate Alert

Warning

CRITICAL: Metal Top Plates

When metal top plate selected, system displays:

“Metal Top Plates are set FLUSH to Top of Concrete. Please check and adjust Panel top elevations if necessary.”

WHY: Metal deck typically sits ON TOP of concrete, so plate must be flush. If plate protrudes above panel top ? deck won’t sit flat! If recessed ? deck unsupported!

SOLUTION: Verify panel top elevation = required deck elevation exactly.

Arch Top Restriction

Incompatibility:

  • Arch top panels CANNOT use embed arrays for top plates

  • Curved edge prevents uniform array spacing

  • Must use individual placement or special curved plate

  • System warns if attempted

Engineering Considerations

Load Transfer

Roof Loads to Panels:

Typical Metal Deck Connection:
- Deck gauge: 18-22 ga
- Puddle welds to plates every 12"-18"
- Each plate carries ~500-2000 lbs
- Spacing based on deck span and loads

Wood Rafter Connection:
- Rafter bears on wood plate in pocket
- Bolted or toe-nailed connection
- Plate carries rafter reaction (2-8 kips typical)

Concrete Panel Bearing:
- Bearing strip at panel top
- Grout between panels
- Bearing stress calculations required

Spacing Calculations

Metal Deck Typical:

  • Plate size: 4” × 6” × 1/2”

  • Spacing: 4’-0” on center

  • 12’ panel ? 3 plates

  • 20’ panel ? 5 plates

Wood Rafters:

  • Rafter spacing: 16” or 24” on center

  • Pockets match rafter spacing exactly

  • Must coordinate with roof framing plan

User Example

Scenario: Metal roof deck on 20’ panel

1. Type: Metal plate flush
2. Dimensions: 4" × 6" × 1/2"
3. Array: Enable
4. Spacing: 4'-0" on center
5. Edge distance: 12" from each end

Calculation:
- Panel width: 20'-0" = 240"
- Usable width: 240" - 24" (edges) = 216"
- Number of plates: 216" / 48" = 4.5 ? Use 5 plates
- Actual spacing: 216" / 4 spaces = 54" = 4'-6"

Result: 5 plates @ 4'-6" spacing, 12" from each edge
Alert: "Metal plates flush - verify panel top elevation"

Integration

Called By: mp_dlg ? [Top Plate] (mptp)
Drawing: Top plate symbols with weld symbols and dimensions

Variables:

  • tpt - Plate type

  • tpw, tpl, tpthk - Dimensions

  • tps - Spacing

  • tpe - Edge distance

  • tpa - Array enable

  • tpf - Flush flag

  • tpr - Recess depth

Special Checks:

  • Arch top incompatibility (updvar.lsp)

  • Flush plate elevation warning

  • Array spacing validation

Best Practices

Metal Plates:

  • ? Always flush to concrete top

  • ? 4’-0” to 6’-0” spacing typical

  • ? Minimum 1/2” thickness for welding

  • ? Verify deck layout matches plate spacing

Wood Plates:

  • ? Pocket depth = wood thickness + 1/2”

  • ? Match rafter/joist spacing exactly

  • ? Provide drainage (slope bottom of pocket)

  • ? Treated wood if outdoor exposure

Concrete Bearing:

  • ? Grout between panels (typical)

  • ? Bearing strip width ? 4”

  • ? Check bearing stress (0.85f’c limit)

  • ? Roof panel alignment critical

Common Mistakes

Avoid:

  • ? Metal plates not flush (deck won’t sit properly)

  • ? Wrong spacing (doesn’t match deck/rafter layout)

  • ? Too close to panel edge (< 6” - concrete breaks)

  • ? Arch top with array (geometry conflict)

Documentation Metadata

Enhancement Status: ? COMPREHENSIVE - RECREATED [5/13]

End of Document