BASIS 90 x 90 Concealed Post Connector – Column Mounting System

The BASIS 90 × 90 is a concealed column mounting connector designed for the precise and durable attachment of timber columns and posts to solid substrates such as concrete, stone, or masonry. As an extension of the ACRO system, the BASIS connector integrates a pre mounted ACRO connection on a galvanized steel base plate, allowing columns to be installed cleanly, securely, and with minimal visible hardware.

The connector enables a self tensioning, force fit connection between the column and the base surface. Once installed, only a narrow joint line remains visible, making the BASIS 90 × 90 well suited for architectural and interior applications where appearance and precision are critical. The system allows disassembly at any time and does not restrict the natural movement of the wood.

The BASIS system is intended for fixed column and beam connections and is not designed for freestanding columns.

Key Features

• Concealed column to base connector for solid substrates

• Self tensioning force fit connection

• Disassemblable connection for maintenance or adjustment

• High degree of prefabrication for efficient installation

• Adjustable contact pressure via fastening screws

• Durable galvanized steel base plate

• Tested load bearing performance

• Manufactured from high strength, weather resistant steel

• Timber columns and posts mounted to concrete or masonry

• Interior timber structures and architectural installations

• Exhibition and trade fair construction

• Museum installations and display structures

• Conservatories and light timber framing applications

Included in the Set

• 1 BASIS 90 x 90 base plate assembly

• Pre-mounted ACRO 90 x 90 connector

• Galvanized steel base plate, factory assembled

Required Fasteners (not included)

• End grain wood connection:

  • 8 pcs self-tapping screws 6 x 60 mm

• Base plate anchoring:

  • Base plate pre-drilled for 1 pc M12 masonry anchor

Load Capacity

• F0 = 3.99 kN

• Load value refers to shear force in the insertion direction

• Based on testing by Holzforschung Austria

Material

• High-strength, blue-zinc-plated, weather-resistant steel

• Manufactured in Austria

Notes

• Designed for concealed, force-fit mounting of columns to solid surfaces

• Only a minimal visible slot remains after installation

• Not suitable for freestanding columns

• Compatible with standard self-tapping screws per Austrian Standard ONORM M5027

For concealed installation, a recess is milled into the column end grain or longitudinal grain to a depth of 13 mm using a slot cutter with a 15 mm diameter. The base plate is anchored to the solid surface, and the column side connector is inserted and engaged to create a secure, self tensioning connection.

The system supports installation using handheld routers or CNC machining and is well suited for both shop prefabrication and on site assembly.