Drop Panel Rebar — hosts, mats and links
Open Drop Panel Rebar for existing thicker native drop Floors and a reference main slab. This differs from positive geometry in Mushroom Slab Review and straight mats on the original Floor in Mushroom Slab Rebar. DirectShape drops/capitals are not native Floor hosts.
Select hosts and create reinforcement
- Open a project with native Floors for both the thicker drop and thinner main slab. Preselect only the drop Floors and run Drop Panel Rebar. With an empty or mixed-category selection, pick the drops and Finish; then pick the MAIN slab Floor. The main cannot also be a selected drop. Esc cancels picking. A Mushroom Review DirectShape cannot host this reinforcement.
- In Drop host, turn on Enable drop-panel steel and check eligible candidates. Read type, material, thickness, join and rejection reason. Expected total thickness includes the main; expected additional depth is only the portion below it. Total 350/main 200 means additional 150 mm. A zero expected value skips that cross-check; it does not specify zero thickness.
- In Drop mats, enable each Top/Bottom X/Y direction and choose outside cover, layer order, D/spacing, offset and setbacks. For four straight mats, leave hooks None and U/transition/links disabled. Their controls remain available for review but contribute only when enabled.
- In Drop check, expand Actual Revit bar and hook types and resolve every group. Entering D12 does not choose among several D12 types. A90°/135°/180° hook request exposes the actual start/end hook selectors. Inspect the plan and both cuts, then Check Revit readiness. Changing inputs invalidates readiness: check again before Create / Update drop steel.
- Read created/replaced/developed-length results. Close the tool and inspect native Rebar in 3D/sections. Preview count, tool-owned count and all reinforcement on a host differ. Screenshots use the actual English production UI; the saved model evidence follows the reference below.
1 selects recipient hosts; 2 cross-checks depth, covers and limits; 3 changes the reviewed host, filters and cuts. The toolbar Host changes the preview, while candidate checkboxes define recipients.
Faces, directions and hooks
1 controls top cover/layer order/clearance; 2 is Top X including D/spacing/offset/setbacks/hooks; 3 continues into Top Y. Axes follow panel edges. Cover is outside the nearest bar; offset shifts the grid, while setbacks shorten the main segment at its ends.
Scroll to the bottom: 1 is Bottom cover and layer order, 2 Bottom X, 3 Bottom Y including both ends. Top edits do not automatically copy to Bottom. Inspect cuts after increasing cover or interlayer clearance.
1 shows conditional actual start/end 90° hook choices for Top X. Tail lengths and bend radii come from project types. 2 checks hook direction and layer positions in cuts. This image establishes UI/readiness; native hooked output is verified separately below.
Free edges, transitions and links
1 enables U-bars only at correctly classified free edges; continued edges are refused. Leg length is geometry from the web, not a designed development length. 2 starts transition X.
1 transition X and 2 transition Y each have a face, D/spacing, offset, rise/run/tail and center depth. Zero center depth uses automatic mat-stack clearance. Main-slab continuation is explicitly unsupported: a checkbox cannot make one bar have two hosts.
1 selects closed stirrup/single leg and actual hooks; 2 chooses support arms, first distance from the support face, pitch/count and strip geometry; 3 reviews enclosure and the detailing-only acknowledgement. Legs across/leg spacing serve the single-leg layout. Drawn links do not verify punching resistance; headed stud rails are unsupported.
Readiness, retained warnings and scoped removal
1 contains diagnostics; 2 separates readiness, Remove and review export; 3 opens the actual-type expander, which must be scrolled to its end.
1 resolves all four mat types; 2 is the plan/cut preview. OVERLAP_NOT_JOINED means overlapping Floor solids still double-count concrete. Review the model/join and concrete quantities, or retain the warning for an intentionally reviewed overlap. VALID DETAILING GEOMETRY neither removes that warning nor establishes structural capacity.
Remove this add-in's drop steel removes owned reinforcement on selected hosts and preserves manual steel. Reopen the tool after host geometry/join changes to refresh its context. Review export does not create Rebar.
Every input group and action
| Control / setting | Unit, condition, effect and verification |
|---|---|
Drop host / existing main Floor / candidate selection | Select existing drop Floors and the reference main Floor. Read eligibility/reason and total/main/additional depth. A DirectShape is not a Rebar host. |
Enabled / HostUniqueIds | Enable the layout for the selected host list; one layout is applied to each host. |
ExpectedTotalThicknessMm / ExpectedAdditionalDepthMm | Optional thickness cross-checks in mm; 0 means unspecified. Additional depth is distinct from total thickness. |
SideCoverMm / BarClearanceMm / RotationDegrees | Side cover, inter-bar clearance and panel-relative angle. Compare actual host cover and clashes; these are not anchorage calculations. |
MinimumBarLengthMm / MaximumBars | Minimum fragment length and maximum bar count; inspect diagnostics for rejected fragments/limits. |
Top/Bottom.CoverMm / XNearestFace / InterLayerClearanceMm | Clear cover to the nearest bar surface, X/Y order and layer gap; inspect X/Y sections. |
Top/Bottom.X/Y.Enabled / DiameterMm / SpacingMm / OffsetMm | Enable each direction; diameter/pitch and perpendicular grid offset from panel center. Each native Rebar is a single bar. |
Top/Bottom.X/Y.StartSetbackMm / EndSetbackMm | Extra end setback beyond side cover, not anchorage. Increasing it shortens the main run. |
Top/Bottom.X/Y.StartHook/EndHook.Kind / Direction | None/90/135/180 and toward the same/opposite face. Resolve compatible actual hook types at each end and inspect read-back angles/length. |
UBars.Enabled / EdgeMinX / EdgeMaxX / EdgeMinY / EdgeMaxY | Enable U-bars on reviewed eligible/exposed edges; do not blindly enable every interior edge. |
UBars.DiameterMm / SpacingMm / OffsetMm / LegLengthMm | Diameter, pitch, offset and horizontal leg length from web centerline to end; inspect edge containment. |
UBars.TopLegCenterDepthMm / BottomLegCenterDepthMm / YEdgeLegDepthShiftMm | Leg center depths; 0 clears the enabled mat stack. Y-edge depth shift nests corner legs toward mid-depth; zero can cause corner clashes. |
TransitionX/Y.Enabled / Face / DiameterMm / SpacingMm / OffsetMm | Enable X/Y transition bars, choose the middle-run face and its diameter/pitch/offset. |
TransitionX/Y.RiseMm / RunMm / TailLengthMm / CenterDepthFromFaceMm | Rise, sloped-run projection, tail and middle-run center depth (0 clears the mat stack). Inspect sections and centerline length. |
TransitionX/Y.ContinueIntoMainSlab | One Rebar cannot have two hosts; this request is unsupported. Main-slab continuation needs separate bars/detailing. |
Links.Enabled / Kind | ClosedRectangular/SingleLeg; HeadedStudRail is unsupported. Drawn links do not prove punching resistance. |
Links.DiameterMm / CoverMm / HookKind | Diameter/cover and hook kind; choose compatible actual stirrup/hook types and inspect angles in Revit. |
Links.ArmPlusX / ArmMinusX / ArmPlusY / ArmMinusY | Four support arms; enable intended arms and inspect each arm’s quantity. |
Links.FirstDistanceMm / SpacingMm / CountPerArm | Distance from support face to first link centerline, pitch and count per arm. First distance is not measured from column center. |
Links.StripWidthMm / TransverseOffsetMm / LegsAcross / TransverseSpacingMm | Outer strip/link width, transverse shift, number of legs and transverse pitch. Check mat enclosure and clashes. |
Links.RequireMatEnclosure / DetailingOnlyAcknowledged / PunchingVerificationReference | Require mat enclosure, explicitly acknowledge detailing-only scope and record the independent punching verification reference. |
AcknowledgeUncheckedSystemSteel / DesignBasisNote | Acknowledge unchecked system reinforcement on the main slab and record design basis. Acknowledgement does not perform the missing check. |
Drop check / type and hook selectors | Resolve actual bar/hook types for each group/end. A D12 setting alone does not resolve types. |
Check Revit readiness / Create / Update / Remove | Check the current model before creation; edits invalidate readiness. Update replaces owned bars and Remove deletes owned bars only. Reopen after host changes. |
Verify and save
Check total/main/additional depth, Host, actual hook angles, cover and length. Preview counts do not substitute for committed elements/Properties. Save settings and save the RVT separately; reopen prepared section views. Drawn links do not establish headed-stud support, main-slab anchorage or punching resistance.
Verified result
Installed package 2026.10.23.2046 in Revit 2024: production services and UI Create/Remove were exercised. The hooked/link sample was opened in a fresh Revit process:72 owned bars plus 1 preserved manual bar; native Bar Length totals 194.090 m. A separate Xhome copy has a reader-eligible 400/150 mm drop/main pair; that check is distinct from the educational output. Ribbon/license/picking entry remains untested.
Additional controls and visibility
| Control | Condition and effect |
|---|---|
Preview Host / candidate checkbox | Toolbar Host selects the preview host; candidate checkboxes select layout targets. Refused candidates are disabled. |
Layers / All, Top, Bottom, U + transition, Links | Filters the plan preview only; it does not delete elements or toggle group creation. |
X cut y= / Y cut x= / Snap to bar | Panel-relative cut coordinates in mm: the X section uses y and the Y section uses x. Click the plan to move cuts; Snap to bar moves cuts to nearby bars without changing steel. |
Actual Revit bar and hook types (expander) | Expand in Drop check and scroll through group/start/end selectors. It auto-expands for unresolved/type-diameter errors. Type Id presets apply to their document only. |
Export drop review | A host plan enables review export, potentially with diagnostics. Export does not create steel; inspect validity in the package. |
Splitters / plan and X,Y sections | Drag splitters to resize settings/plan/sections without changing geometry. These are tool canvases; inspect actual 3D in Revit after creation. |
Reopened model and actual Properties
These examples have different scopes. The four-straight-mat UI above created 60 D12a200 bars and removed them through the tool. The hooked/link 3D example below retains 72 owned bars:15 Top X,15 Top Y,15 Bottom X,15 Bottom Y and 12 links. One manual bar is preserved, making 73 on the host. Both use illustrative 350/200 mm drop/main Floors and are distinct from the 400/150 mm existing Xhome pair.
The hooked/link result was saved and opened in a fresh Revit 2024 process. All 72 owned bars persist, each Quantity 1; native Bar Length totals 194.090m, including bends/hooks. This differs from a hook-suppressed polyline total and rounded-length parameters. Repeat/update replaced owned bars while preserving manual steel. This is production service/UI evidence rather than a complete ribbon-picking entry run.
1 identifies four committed native mats; 2 the links around the support on the same host. The image is an exact pixel crop from reopened Revit output, not the tool canvas.
1 actual D12 type; 290° hooks at both ends; 3 Single layout/Quantity 1; 4 Bar Length 3063.3 mm versus rounded Total Bar Length 3060 mm; 5 Floor host category. Project-defined parameter names may remain Vietnamese in English Revit. One bar's Quantity is not the host total.
1 D10 Stirrup/Tie with 135° hooks at both ends; 2 Quantity 1/Bar Length 1331.4 mm; 3 selected native link with visible legs/hooks. Link geometry does not establish punching resistance. Only illustrative components are pictured; the private-derived RVT remains internal and is not a public download.
Deliberate edits and saving
On a copy, try mat spacing 200→240 mm, inspect preview/types/readiness and Update: mat counts generally fall while link layout is independent. Decreasing pitch increases density; compare each group separately from manual steel. A diameter change also requires actual-type/hook compatibility review. Reopen the tool after host or join edits.
Tool Save/Open handles JSON; Ctrl+S saves the RVT. Close/reopen and inspect prepared 3D/plan/section views for host/count/hooks. Only separately verified educational practice packages are linked for download; a private project copy is not a public practice model.
Existing project Floor pair and cover limitation
On an existing 400/150 mm Floor pair, the reader recognized the drop configuration and the production service created 2 straight D12 bars totalling 4.014 m. Repeating replaced 2 with 2 while preserving out-of-scope steel. All four mat directions were enabled, but only Top.Y/Bottom.Y had valid paths on this footprint; four enabled controls do not imply four nonempty groups. This differs from the 72-bar hook/link example above. The private project result is not a public download.
Host covers greater than 25 mm: with package 2026.10.23.2046, an educational host with actual 30 mm covers was rejected during recognition with COVER_BELOW_HOST_TOP/BOTTOM/SIDE at 25 mm, before configured 40 mm covers reached planning. Preserve this diagnostic and check supported package versions; do not reduce the Floor's design cover to force eligibility. A blocked case is not a valid output model to publish.