Designing and modeling convincing railings is often a lengthy process, especially when you want to test, visualize and compare different variations in your daily workflow. This is exactly where BARRIER comes in. With this Grasshopper tool, you can generate precisely modeled railings with complete flexibility from any base curves. Whether the curves are open or closed, a single line or a complex network, BARRIER adapts perfectly to your design.

➔ BARRIER takes the repetitive modeling work off your hands so you can concentrate fully on the design of your project.

Handbook

Please note that the script operates in centimeters, so make sure to set up your file and enter all values accordingly.

Base Setup

The main component "Create Railing" is all you need to get an immediate result. Very few inputs are needed. Advanced input options are available:

Input "Type": The input uses numerical values to select the different railing variations. A visual preview is available directly within the Grasshopper canvas. Currently, you can choose between these variations:

Input "RUN": This toggle enables or disables the computation through a boolean value. Pausing the calculation while modifying base curves is highly recommended, particularly when sourcing your geometry directly from a Geometry Pipeline component.

Input "Base Crv": Connect your three dimensional curve geometries here. The tool is highly versatile and accepts a wide range of inputs, including open or closed curves, multiple curves simultaneously, circular paths and complex splines.

Input "Form": This numerical input handles the automatic segmentation of your railing. If you are using curved geometry for your base path, this feature allows you to effortlessly divide it into precise straight sections.

Input "Height": This parameter defines the absolute height of the railing. It sets the exact vertical distance measured from your base curve directly to the top edge of the handrail.

➔ The Output geometry is sorted by most likely used materials.

Advanced Input Options

If you want to dive deeper into the design, you can use the AIO input (Advanced Input Options). This allows you to individually set specific parameters for the main pillars, handrails, basepoints and panels.

Main Pillar Options:

Distance: This parameter defines the spacing along the curve between the main pillars. Pillars are automatically placed at every corner of your base geometry. The sections between these corners are then divided equally so that the maximum spacing never exceeds your inputted value. Consequently, the actual distance between pillars might be slightly smaller than your specified number, which is a deliberate design choice to ensure an even distribution.

Radius: Sets the overall radius of the main pillars in centimeters. If you choose a profile other than round, this exact number will define half of the side length of the geometry instead.

Thin Top Length: Physical railings often use a narrower pillar extension above the paneling to support the handrail. This reduced diameter ensures a hand can slide along the top continuously without bumping into the thicker structural posts. Use this value to adjust the exact length of this thinner top piece.

Thin Top Radius: Sets the exact dimension of the thinner top piece. This value dictates the circle radius or, depending on your chosen pillar geometry, represents half the width of the straight sides.

Type: A numerical input that defines the shape of your pillars. Entering "0" selects a round profile, while "1" selects a square profile. This setting dictates the geometry for both the main pillar body and its thinner top section.

Handrail Options:

Form: This numerical value dictates the specific geometry of the handrail. Select "0" to inherit the global form, "1" to force straight segments "2" and to ensure a smooth curve. Decoupling the handrail shape from the underlying panel geometry allows for great creative freedom. A segmented rail above a curved net or a perfectly smooth handrail over faceted panels often produces highly compelling architectural designs.

Radius: Defines the overall size of your handrail geometry. For a circular rail, this is the standard radius. If you select a square or different profile, this numerical input determines half the overall width of the shape.

Type: A numerical input determining the profile of your handrail. Enter "0" for a round shape, "1" for a rectangular design, or "2" to remove the handrail completely.

Height: This parameter exclusively affects the square handrail profile. It dictates the total vertical dimension of the rail, giving you the freedom to create flat or elongated rectangular shapes independently of the width setting.

Cap: When working with open base curves, your handrail will naturally have exposed ends. By default, these ends feature a straight cut. However, if you are using a round handrail profile, you can choose to make the ends spherical. This allows for designs where the handrail and the main pillar merge flawlessly, especially when both share the exact same radius.

Extension: For open railings, the handrail can extend beyond the last main pillar. Use this numerical value to determine exactly how far the handrail protrudes outward at the open ends of your base curve.

Base Point Options:

Top Z Offset: This parameter establishes the top edge of your base point geometry in the vertical Z direction, measured directly from the base curve. A positive numerical value positions the top edge above the curve, while a negative value places it below.

Type: A numerical input used to select the specific geometry and alignment of your base points. Enter "0" for no base, "1" for a flat round base, "2" for a round base that follows the topography, "3" for a flat square base, "4" for a square base following the topography, or "5" for a side mount attachment. This parameter gives you the flexibility to choose between cylindrical and rectangular shapes. Furthermore, you can decide whether the top surface of the base remains perfectly horizontal or adapts seamlessly to the three dimensional slope of your base curve.

Width: This parameter defines the overall horizontal size of your base point geometry. Depending on the specific type you selected previously, this numerical value determines either the full diameter of a cylindrical base or the total width of a square base.

Height: This parameter defines the exact vertical thickness of your base point geometry. It allows you to directly control how tall the base element geometry will be.

Side Offset: Crucial for the side mount option, this value defines the outward extension of the geometry. Positive and negative numbers control which side the mount faces. Because this relies on the inherent direction of your geometry, you must monitor your curve orientations carefully. If a mount extends inward instead of outward, you can easily fix this by applying the Flip Curve command in Rhino to the affected base curve.

Panel Options:

Sides Offset: This parameter dictates the clear horizontal gap between the edge of your panel geometry and the adjacent main pillars. It allows you to create a visual separation between the inner material and the primary vertical supports.

Bottom Offset: This parameter establishes the clear vertical gap between your starting base curve and the lowest edge of the panel geometry. It allows you to easily lift the filling material slightly off the ground level or the base point structure.

Top Offset: This parameter determines the clear vertical distance separating the upper edge of your panel geometry from the handrail above it. It allows you to create a neat open gap at the very top of your filling material.

Radius/Depth: This parameter determines the radius of both the internal struts and the surrounding panel frames. Additionally, it controls the overall depth of solid planar elements. Please note that solid surfaces are automatically generated to be exactly half as thick as their supporting frames to ensure a realistic structural hierarchy.

Bar Distance: This sets the clear gap between struts within your panels. Since overall panel widths change depending on the pillar placement, your input serves strictly as a maximum distance limit. The system automatically calculates equal spacing for each specific panel, meaning the final gap might be smaller than your exact input to guarantee a perfectly uniform and symmetrical look.

Net Give: This setting specifically controls the amount of sag or slack in the mesh when you are using the net panel type. Because this is a purely relative value rather than an absolute measurement in centimeters, you should simply adjust it based on your visual preference to achieve the most natural suspension for your specific design.

Advanced Output

The "Advanced Output" Component provides maximum control over your final renders, all individual geometric elements, such as handrails and base points, are sorted into separate output lists. This organized structure allows for deep customization and effortless material assignment when preparing your architectural model for professional visualization.