Layout Assist is currently in beta. We are continuing to improve lot splitting and building placement. Use generated layouts as a starting point for review and refinement.
Layout Assist uses a road layout and assigned lot products to create parcel layouts and concept building footprints. The walkthrough uses a Florida subdivision example in Civil 3D. The first view shows the lots and concept building footprints generated around a cul-de-sac on the east side of the site. Example dimensions are in feet and square feet.
The eastern cul-de-sac in the sample subdivision. Orange outlines show parcels, green outlines show concept building footprints, and magenta lines show the road alignment.
Prepare the drawing
Initialize the Allsite project, select the existing ground surface and confirm the coordinate system and project units. Define the earthworks extent and roads. For a copied demonstration drawing, choose Duplicate in Resolve Project Link to keep a separate project for the copy.
Simple roads need their profiles, profile views and corridor before the parcel workflow. Use Check Roads and Generate Road Corridor. Where an existing corridor is already the input, retain that corridor and review its assemblies and product assignments.
Find the Layout Assist commands
Layout Assist on the Allsite.ai ribbon.
Generate each output from the Generate Others menu.
On the Allsite.ai tab, open the Layout Assist settings gear to review the project defaults. Use Generate Others > Generate Parcels, then Generate Buildings for the concept footprints. The same menu contains Generate Driveways and Generate Potential Grade Breaks. Progress, generated counts and review messages appear in the AI Assistant pane.
Choose closed polylines or Civil 3D parcel segments
The Parcel output type setting has two choices. Closed polylines per lot produces one editable closed outline for each lot and does not create native Civil 3D parcels. Use it while adjusting the layout before building the parcel fabric.
Civil 3D parcels creates native parcel objects from shared parcel boundary segments. Adjoining lots meet on one segment rather than two independently drawn edges. Choose this option for the parcel-segment workflow.
Civil 3D derives parcels from the enclosed segment network. To combine adjacent native parcels, remove the shared internal parcel segments while preserving the outside boundary. Deleting a parcel label or merging copied polygon outlines does not remove that internal parcel fabric.
Output structure illustration. Shared polyline edges are drawn apart only to make their ownership visible.
Set up parcel generation
Open Project Properties → Settings and filter to Layout Assist. Check that Generate parcels is enabled. For lots that front a cul-de-sac, review where lot depth is measured using the diagram below. See Edit Project Settings for help finding these controls.
The parcel generation settings diagram illustrates the lot dimensions and shows where cul-de-sac lot depth is measured.
Check road layout settings
Confirm the road category and review the corridor or simple road dimensions before generating lots. The Road Layout Settings reference explains the road-category defaults and where to set dimensions on individual roads.
Road layout parameters. Use the road-category table and the road properties for the numeric values.
Assign lot products
In Project Properties, open Lots → Lot product parameters. Choose the product for each side of the road in the simple road properties or on the corridor assembly. Check the values on the road before running Layout Assist. See Project settings, feature values and the Settings Report for how defaults and overrides work.
At the Florida cul-de-sac, the lot product uses a 4,000 sq ft minimum area, 100 ft minimum depth and 40 ft minimum frontage. The road sets a 130 ft maximum depth. A maximum depth can leave space between opposing rows of lots.
Review and refine the generated model
Check lot shapes, frontage and depths at bends, intersections and cul-de-sacs. Review leftover areas and classify every parcel for its intended use. Check building footprints against lot boundaries, setbacks and access. Adjust or remove footprints that do not suit the concept.
Elsewhere in the same subdivision, 13 lots inside a road loop were combined into one 1.77-acre native parcel by deleting the internal dividers. Its category was set to PUBLIC PARK and its 13 building footprints were removed.
The road loop after the 13 lots were merged and the building footprints were removed. The resulting 1.77-acre parcel is classified as PUBLIC PARK.
Lock generated lots you want to retain across parcel-generation reruns. Review the run card and any review messages after each run. A finished generation operation is not a substitute for checking the layout.
Parcel grading and building settings
When you take the selected layout into Level AI, review the default parcel grading settings and default building settings.
Related lot-grading settings apply when developing the selected layout in Level AI.
Run Level AI and Service AI
Once you’ve reviewed the layout and checked the required grading and servicing inputs, the model is ready for a combined run. Level AI optimises design levels to balance cut and fill. Service AI uses those levels to design an optimised pipe network.