SWITCH | SQUARE

The Square Switch by Sumum is an 8 mm square push-button set in a 4 mm solid brass plate. Where the Round switch feels softer and more classic, the Square has sharper lines and a more architectural presence – ideal when you want the switches to subtly echo the geometry of your interior.

Each plate is milled from solid brass and finished by hand in Sumum’s signature metal tones. The small square button sits slightly proud of the surface, catching light on its edges and creating a quiet, graphic rhythm on the wall.

Technically, the Square is a low-voltage push-button with potential-free contact, designed for use with KNX, QBUS, DALI and other smart home or central relay systems. The intelligence sits in the electrical cabinet; the Square button simply sends the command – for switching, dimming, blinds, scenes and more.

At Numa Home, we curate the Square Switch for calm, refined interiors in the Netherlands and Turkey – from townhouses and apartments to villas, boutiques and hotels. You can choose from different button layouts (1–5 buttons per plate) and match the finish with Sumum outlets, Light Tubes and cabinet hardware for one coherent brass story throughout the project.

Designed by Wesley Demeester for Sumum, curated by Numa Home.

Numa Home is the official distributor of Sumum in the Netherlands and Turkey. For orders outside these countries, please contact Sumum directly.

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Production & lead times

Sumum products are made to order in Belgium. Delivery happens in two stages:

First delivery – internal mechanisms
– Lead time: ≈ 4–6 weeks
– The electrician can already mount and wire these in the wall or panel.
– As soon as they are installed, the installation is fully functional.

Second delivery – brass cover plates
– Lead time: ≈ 8–12 weeks
– The solid brass plates are clicked onto the mechanisms on site once all finishing works are done.

Two-stage delivery
This two-stage approach keeps the project moving: first the technical installation, later the finished brass plates once painting and wall finishes are complete.

Made-to-order & order changes
Every Sumum piece is custom-built in your selected configuration and finish.

Once the order is confirmed, specifications and quantities cannot be modified or cancelled.

For any questions or updates, please quote your order reference and write to info@numahome.nl.

Countries

Netherlands
Numa Home is the official distributor of Sumum in the Netherlands.

Orders are shipped from Belgium to your address or project site. Once production phases are completed, shipping within the Netherlands usually takes a few working days.

Turkey
Numa Home is also the official distributor of Sumum in Turkey.

We organise transport from Belgium to Turkey. Transit time is typically around 7–10 working days after dispatch, depending on destination and shipment size. Exact costs and timings are calculated per order.

Other countries
For orders outside the Netherlands and Turkey, please contact Sumum directly to discuss availability, local partners and shipping options.

We work closely with architects and interior designers on a project basis.

Please contact us for B2B conditions, samples and project pricing in the Netherlands and Turkey via info@numahome.nl

Electrical concept
– Action: momentary push-button – springs back after each press.
– Contact type: potential-free (NO).
– Rated voltage: AC max. 230 V.
– Rated current: max. 0.1 A.
– Designed to work with relays, dimmers, KNX / QBUS modules and other smart home interfaces in the electrical cabinet – not for direct 230 V load switching.

System integration
– KNX: connect Square buttons to KNX binary inputs / push-button interfaces; KNX handles switching, dimming, scenes, blinds, etc.
– QBUS: Square can be mounted on dedicated QBUS PCBs behind the plate, connecting directly to the QBUS bus and offering multiple buttons, status LEDs and optional sensors.
– DALI / DALI-2: by using DALI push-button couplers, each button can send on/off, dim and scene commands to DALI drivers.
– Central relay / smart panels: in more traditional set-ups, each Square button operates a relay or universal dimmer module in the electrical cabinet.

Layout & mechanics
– Button size: 8 × 8 mm push-button (square).
– Plate thickness: 4 mm solid brass.
– Single plates: 1–5 buttons; double modules up to 10 buttons when combined.
– Typical 2-gang plate dimension: approx. 85 × 85 mm (varies per region; detailed tech sheets available).
– Compatible with standard European 60 mm wall boxes (BE / FR / NL / DE); deeper boxes are recommended where extra modules sit behind the switch.

Use cases
– High-end residential projects, hotels, clinics, offices and galleries.
– Control of lighting, scenes, blinds, HVAC or other functions via your chosen control system.

Distribution
– Numa Home is the official distributor of Sumum in the Netherlands and Turkey.
– For orders outside these countries, please contact Sumum directly.