Configure floors and foundation walls

Choose the floor system

In Building mode, use the floor bar below the preview. Floor joists exposes joist dimensions and material, subfloor settings and Ready for insulation. Edit these directly; there is no separate Floor options popup.

Foundation (garages) creates a concrete perimeter baseline with its own editable height and fixed wall thickness. Its tab and preview faces are concrete grey. Floor-joist and subfloor controls are unavailable in this mode. With Textures enabled, generated foundation walls use concrete while the timber bottom plates above them keep spruce.

Foundation opening heights start at the ground floor, below the foundation top. A door or garage door with zero sill height reaches that floor; window sills use the same reference. Timber-joist builds measure openings from the finished floor. Check this reference in Openings before generation.

Internal walls at the floor

Floor planner partitions in a Foundation wall building start at the interior floor, below the exterior timber bottom plates. Finish panels and internal door frames reach that floor too. Automatic wall height still reaches the existing wall-top elevation: a 350 mm foundation and 2400 mm exterior walls give a 2750 mm partition. A custom partition height is measured from the interior floor.

Joist-supported partitions start at their floor surface. Upper-storey and loft partitions use their own level elevations. Regenerate an older building if its ground-floor partitions still float at foundation-top height; reopening the saved model alone does not rebuild them.

Upper-floor joists

With two storeys selected, Upper-floor joists appears beside Floor joists in the viewport. Set 2nd floor joists: width × depth, CC spacing and deck thickness here. The upper floor bears on the lower wall plates and supports the upper walls. Its settings are separate from the ground-floor joists or foundation; switching tabs keeps each configuration. See two-storey buildings for height references.

Subfloor sheets

Choose chipboard, OSB or custom sheet dimensions. Sheet size affects generated panel layout and list quantities, so enter the product that will actually be priced. Inspect edge conditions rather than assuming every remainder represents an orderable full sheet.

A-frame loft floors

With an A-frame host and Loft Floor Deck enabled, a Flush Wall gable dormer over the main bottom chords can extend the loft floor into its opening. Panels continue beneath the raised front plate, stagger on bottom-chord centerlines and notch around retained framing. Projecting building extensions use a separate floor arrangement. See gable extensions and A-frame dormer floors.

Floor insulation

Ready for insulation starts enabled for new timber-joist designs and the Default building preset. It prepares the assembly without adding insulation material as a quantified product. Saved designs and presets retain their own choice; add real insulation products to estimating workflows separately where required.

Foundation (garages) always turns floor preparation off, including when loading an older preset or draft. Switching back to Floor joists restores the previous choice. The wall preparation setting is independent and is not changed by the floor tab.

Check the output

Expand the floor group, measure the joist depth and inspect the Cutlist/BOM categories. For a foundation wall, compare the perimeter with the wall footprint. Neither option validates bearing, reinforcement, moisture protection or structural capacity; those decisions remain project responsibilities.