Alphabetical by name of thing. Please suggest improvements and additions. Note: I change the date whenever I update this, so it will pop up every now and then. Rest assured it's not all new. Big changes will have a post of their own.
Changes in this update: S Wall layers, the fireplace stuff, A Roof2 (roofs in plan), CenterLine & CenterPoint objects, gross area calculation, room name object moves to A Zones.
| Item | Layer | Note |
| Area Calculation Fill | Z Measurement | Use zones instead. |
| Baseboard | F Trim Int Lo | |
| Bathtub | P Fixture | |
| Beam, Structural | S Beam | Control 3D/Section display in object settings. |
| Beam, Structural | S Framing | Hidden in 3D. Alternate to setting control above. |
| Bench | A Cabs2 | |
| Bookshelves | A Cabs2 | |
| Bracket | F Trim Int/Ext Hi/Lo/Mid | |
| Builtins | A Cabs2 | |
| Builtin Labels ("Bench") | +A Arch Note Reg Scale | |
| Cabinet | A Cabs2 | To display in Plan & 3D; use thin, dotted line |
| Cabinet | A Cabs3 | To display in 3D only |
| Car; Plan | F Furniture | |
| Ceiling | A Ceiling3 | |
| Ceiling Finish | F Clg Fin3 | Drywall, panels, etc. |
| Centerline Object | +A Arch Note Reg Scale | To display in Plan, otherwise ! Guide |
| Centerpoint Object | ! Guide | |
| Chimney Parts | A Fireplace | To display in Plan & 3D |
| Chimney Parts | A Chimney3 | To display in 3D only |
| Clip Line (Ceiling) | A Soffit2 | |
| Closet Shelf | A Cabs2 | |
| Coffer Beams | A Soffit2 | Use a dotted line for the beam or slab. |
| Column, Decorative | F Trim Int/Ext Mid | To display in 3D only |
| Column, Decorative | F Trim2 | To display in Plan & 3D, not in structure |
| Column, Structural | S Column | |
| Cooktop | A Appl | |
| Counter | A Cabs2 | |
| Crown | F Trim Crown | To display in RCP, otherwise F Trim Hi |
| Cutline, Stair | A Stair2 | |
| Deck Railing | A Deck2 | |
| Deck Railing | A Deck Railing | To hide in Structure Plan |
| Deck Structure | S Slab | |
| Deck Surface | A Deck2 | To display in Plan & 3D |
| Deck Surface | A Deck3 | To display in 3D only |
| Drawing Area (Object) | +Z Drawing Area | |
| Drawing Title | Note layer of drawing type | |
| Driveway (Mesh) | L Drive3 | |
| Elec Fixtures | Complicated. | |
| Elec Fixture Symbols, Wall & Floor | E Fixt2 | To display in Elec Plan |
| Elec Fixtures, Wall & Floor | E Fixt3 | To display in Elec Plan, Int Elevs, Views |
| Elec Fixture Symbols, Ceiling | E Fixt Clg2 | To display in EP, RCP |
| Elec Fixtures, Ceiling | E Fixt Clg3 | To display in EP, RCP, Int Elevs, Views |
| Elec Fixtures, exterior, modeled | E Fixt Ext3 | To display in EP, 1/4" Elevs, Views |
| Elec Fixtures, exterior, ceiling, modeled | E Fixt Ext Clg3 | To display in EP, RCP, 1/4" Elevs, Views |
| Elevator | +A Arch Note Reg Scale | |
| Energy Calculation Fill | Z Measurement | |
| Firebox | A Fireplace | |
| Floor Finish Fills | F Floor Fin2 | |
| Flooring, Finish | F Floor Fin3 | |
| Flue Parts | A Flue | |
| Footing | S Footing | Use a dotted line for the slab. |
| Foundation Perimeter on Site Plan | +L House Outline | |
| Foundation Walls & Piers | S Wall2 | To display in Plan & 3D |
| Foundation Walls | S Wall3 | To display in 3D only |
| Furniture | F Furniture | |
| Gutter | F Gutter | |
| Hearth | A Cabs2 | |
| Hotspot (Drawing Aid) | ! Guide, ! Site Guide | Not needed, use sparingly, reconsider. |
| Hotspot (Plan Alignment) | Archicad Layer | |
| Hotspot (Other Alignment) | Note layer of drawing type | |
| House on Site Plan | +L House Line | |
| Joists, 2D Fill | S Framing | |
| Joists, Modeled | S Framing3 | Non-print; S2 Model only. Optional. |
| Mask Fills, S/E | +A Misc Line | |
| Mechanical Fixtures | M Fixture | To display in 3D |
| Mechanical Fixtures | +M Elec Note | To display in Mechanical Plan only |
| Note Leader | Note layer of drawing type | |
| Note Text | Note layer of drawing type | |
| Object Resources | Z Object Lab | |
| Oven, wall | A Cabs3 | To hide in plan. The cabinet goes on Cabs2. |
| Oven, wall | A Appl | To display in plan. |
| Panels | F Trim Int/Ext Mid | The wall with the panel windows. |
| Panels, trim, in slabs/roofs | F Trim Int/Ext Hi | Hidden in RCP |
| Panels, trim, in slabs/roofs | F Trim Crown | To display in RCP |
| Patches | Layer of patched elements | In S/E, use +A Misc Line |
| Picture (Scanned) | Z Image Scan | |
| Pool | A Deck2 | |
| Rafters, Modeled | S Framing3 | Non-print; S2 Model only. As needed. |
| Refrigerator | A Appl | |
| Roof | A Roof2 | To display in plan & 3D |
| Roof | A Roof3 | To display in 3D only |
| Roof Finish (Thin) | A Roof Fin3 | |
| Roof Overhead (dotted) | +A Roof Plan Line | |
| Roof Plan Fills | F Floor Fin2 | |
| Roof Structure (Thick) | A Roof | |
| Roof, Cutting | X Cutting Roof | |
| Room Name Object | +Z Zones | Use zones instead |
| Section Marker (Object) | +Z SE & Detail Object | |
| Section Tool (Cutter) | +Z S/E Tool | |
| Shower Head | P Fixture | |
| Shower Pan | P Fixture | |
| Sink, Bath | P Fixture | |
| Sink, Kitchen | P Fixture | |
| Site (Mesh) | L Grade | |
| Site Boundary | +L Site Line .E | |
| Site Contour, existing | +L Contour.E | |
| Site Contour, new/modified | +L Contour.N | |
| Site Contour Labels | +L Site Note | |
| Site Cutting SEO Operators | X Site Cutting | |
| Soffit, Exterior | A Soffit3 | |
| Solid Element Operators | X Solid Cutting | |
| Stair Arrow | +A Arch Note Reg Scale | |
| Stair Newel | A Stair2 | |
| Stair Railing | A Stair Railing | To hide in Structure Plan |
| Stair Stringer (Wall, Object) | A Stair3 | |
| Stair Tread (Slab, Roof) | A Stair3 | |
| Switch Path (Electrical) | +E Elec Note | |
| Toilet | P Fixture | |
| Title Block, Main | +A Arch Note Reg Scale | |
| Title Block, SK | +Z SK Title | |
| Tree, Model | L Tree3 | |
| Tree, To remain, Symbol | L Tree2.E | |
| Tree, Remove, Symbol | L Tree2.D | |
| Vanity Top | A Cabs2 | |
| Wainscot | F Trim Int Lo/Mid | |
| Wall Poche Mask | +A Wall Mask | |
| Washer/Dryer | A Appl | |
| Zone for Room | +Z Zones | |
| Zone for Gross Area Calc | Z Gross Area | |