How to keep Civil 3D sheets updated after alignment and design changes

Why sheets fall behind the design

A layout viewport shows a window of model space. If nothing ties that window to the design, the sheet is correct only for the design as it stood when the sheet was made. When the alignment shifts, the grading changes or the scope grows, someone has to find every sheet the change touched, move or rebuild its viewport, redraw its match lines, fix the key maps on its neighbours and renumber whatever moved. Missed pieces surface in review, or after the set has gone out.

The fix is to make the sheets follow something that moves with the design. In SheetAgent for Civil 3D that is the tile: a polyline in model space, one per sheet, which the sheet is built from and updated from.

What has to follow a change

Element	What updates it
Viewport and its view	Update Sheets, from the changed tile
Match lines and their labels	Update Sheets, or Update Match Lines on its own
Key map, with the current tile hatched	Update Sheets
North arrow, scale bar and title block attributes	Update Sheets, from the template
Sheet numbers, and everything that shows them	Renumber Sheets, cascading to key maps, labels and the sheet set
Sheet Set Manager entries	Sync SSM

When the alignment moves

Tiles are placed against the alignment at preview. If the alignment is edited afterwards, Health raises a drift warning for that alignment.

1. Open Health and press Update Tiles. The tile positions follow the new geometry. The button appears only while the warning is active.
2. Press Update Sheets on your workflow tab. Only the changed tiles are updated.
3. Press Refresh on Health to confirm the warning has cleared.

In alignment placement the station range each tile covers changes with curvature, fewer stations through a curve and more along a straight, so the alignment stays inside the viewport on every sheet. That is expected, not drift. If you edited viewports on purpose and want to keep those edits, use Normalize VP instead of Update Tiles.

When a tile moves, resizes or rotates

Move or resize a tile polyline in model space and press Update Sheets. The layout for that tile is updated, with its match lines and key maps; tiles that did not change are skipped. Rotate a tile and the viewport view, the north arrow and the match lines re-orient with it, through a full 360 degrees. Rotate the tile in model space, not the viewport in paper space: the tile drives the result.

Changing viewport size or scale

The viewport area is defined once on the template. Redefine it, and Health shows a size drift warning with a Retile button. Retile re-cuts the tiles to the new size and reports the changes; sheets are added or removed so coverage stays intact. To change a single sheet, shrink its tile in model space, or resize the viewport in the layout and choose Model tiles in Normalize VP so the tile updates to match.

Scale is decided at preview. A blow-up of a critical area at a different scale is an added tile: press Add Tile, place it at the scale you want, and press Update Sheets.

Coverage gaps after a change

1. Open Health and press Gap Preview. Non-plotting markers appear wherever tile coverage falls below your minimum.
2. Press Add Tile. It covers gaps at the start, at the end and in the middle, and can add tiles at a different scale or naming.
3. Press Update Sheets, not Build Sheets. Layouts are generated for the new tiles and the rest are skipped.

Numbering and Sheet Set Manager

A change that adds or removes sheets changes the numbering. Renumber Sheets renumbers the set in one pass and cascades to the key maps, the match line labels and the sheet set entries. In alignment and path placement, run Update Match Lines afterwards, because those labels carry station ranges. Then press Sync SSM: it lists what is in sync and what will be added, updated or removed, and matches the sheet set to the drawing once you confirm. Every sync rewrites the page number and total sheet fields from the current order.

A changed title block is a reference change. If the title block Xref changed since the build, a stale-reference indicator appears instead of letting sheets plot from the old one: reload it, press Update Sheets, and press Set TB again if the title block itself changed.

Checking before the set issues

Health compares the sheets with the model and the template and lists what has drifted, each with the button that settles it: viewports resized or rescaled by hand, an alignment that moved away from its tiles, tiles modified since preview, a deleted layout, a missing north arrow or scale bar, a reference that changed since the build. Auto Repair settles the common ones. Run it last, after the updates, so what goes out matches the model.

The limits

• Build once, then Update. Build greys out after the first build by design.
• Layout Adjustment changes spacing on stacked plan and profile sheets only. A sizing change on side-by-side sheets goes through Retile.
• Match lines drawn in paper space are approximate, and Health says so. Model space is the accurate choice, and the only one in path and alignment placement.
• On a project spanning several drawings, changes start in the control drawing; see coordinating sheets across disciplines.

Every button named here is documented in What updates when the design changes.

Questions