# Build a stud partition or a joist floor

Lay out a timber stud frame with noggins and openings, or a run of joists with a trimmed opening, as an advisory layout.

The **Stud frame** and **Joists** generators lay out timber at the centres you give. They are advisory layouts only. KerfCraft does not check spans, loads, fixings or Building Regulations. Get structural design for anything load-bearing.

## Start a stud frame

1. Click **Library…** in the toolbar.
2. Under **Built from parameters**, click **Stud frame**.

KerfCraft inserts a stud frame at a standard size and selects it. You can also open **File ▸ Sample projects ▸ C24 stud partition with door**.

The assistant can also lay out a frame, for example "a 3 m long, 2.4 m high stud partition at 400 centres".

## Change the stud frame

1. Select the frame.
2. In the **Properties** panel, under **Parameters**, change a value and press Enter.

| Parameter | What it sets |
| --- | --- |
| **width** | The length of the frame along the wall |
| **height** | The overall height, plates included, at the left end |
| **heightRight** | The height at the right end, for a sloped head plate. 0 is a level head |
| **profileId** | The timber profile for all members |
| **spacing** | The stud centres. The default is 400 mm |
| **nogginRows** | The rows of noggins in each bay |
| **nogginStagger** | **inline**, or **staggered** for end-nailing |
| **cornerLeft**, **cornerRight** | **threeStud** or **california** corner members where another frame meets this one |

## Add a door or window opening

In **openings**, type each opening. Put a `;` between two openings:

- A door: `door:x=600,w=826,h=2040`
- A window: `window:x=1500,w=900,h=1050,sill=900`

The value `x` is the distance from the left outer edge of the frame to the opening. The values `w` and `h` are the width and height of the opening. The value `sill` is the height of the bottom of a window opening. Each side needs space for a king stud and a jack stud.

The heads over openings are doubled flat members of the frame timber, not designed lintels. The frame shows this warning.

## Start a joist floor

1. Click **Library…** in the toolbar.
2. Under **Built from parameters**, click **Joists**.

KerfCraft inserts the joists at a standard size and selects them. Change them in the **Properties** panel, under **Parameters**.

The assistant can also lay out joists, for example "floor joists 3.6 m span, 2.4 m wide, at 400 centres".

## Change the joists

| Parameter | What it sets |
| --- | --- |
| **span** | The length of the joists, rim boards included |
| **width** | The width across which the joists repeat |
| **profileId** | The timber profile for all members |
| **spacing** | The joist centres. The default is 400 mm |
| **rim** | **both** adds rim boards across the joist ends |
| **opening** | One trimmed opening, for example `x=800,y=1000,w=900,l=1200` |

The opening is in mm from the origin of the frame. The value `w` is along the width, and `l` is along the span. KerfCraft doubles the trimmers and trimming joists round it.

## Before you cut

The **Derived** heading shows results such as the joist count. Check every dimension against your own measurements before cutting.

## Related

- [Use project parameters and expressions](/docs/how-to/furniture/use-project-parameters/)