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Commercial use

Residential projects

Commercial projects




Flush Threshold Drain for Doors

The IQ Flush Threshold Drain system provides a robust and effective water protection and drainage for flush threshold base frame details.

The hidden drainage channel can take up to 90 litres of water per minute and the exposed metal grille is anti-corrosive – suitable for marine environments or in conjunction with a chlorine or salt water pool.

The channel itself is an EPDM silicone sleeve which creates an effective thermally broken water barrier flush with floor tracks and the external floor finish. With a metal slim grate over the top.

Drainage for Flush Thresholds

This versatile drainage solution can be engineered to suit all threshold thicknesses and is available in silver anodised aluminium (in stock) and titanium anodised aluminium (at an additional cost) . Pre made corner drainage channels allow tricky corner sections to be finished as neatly and minimally as the rest of the flush drain.

The square edged drainage has a slim and ergonomic design which makes it heel and small finger safe.

A flush drainage detail allows you to continue the frameless contemporary appearance across your internal floor finishes, across the base frame of your doors, across the drainage top to the external floor finish. This facilitates that internal to external blurring (the indoor outdoor effect) that is so popular within modern architecture, without having to compromise on performance 

IQ Glass Flush Threshold Hidden Drainage System


IQ Glass Threshold Drain

Design Integration

The design team at IQ have created a number of standard design details in order to integrate this flush threshold drainage channel with our flush threshold doors.

This hidden drainage channel is especially useful in conjunction with our slim framed sliding glass doors which have a sub floor level neoprene drainage base that can drain water below the finished floor levels.

Smaller ‘blade drains’ can be incorporated into some of our other flush threshold designs such as the Vitra Pivot.

Maximum Sizes

The Flush threshold drainage channel can be used as drainage across sliding door bases and be designed to continue along building facades or walls. Thanks to the specially designed Connector section with EPDM seal and screw these flush threshold drainage channels can be designed up to lengths to suit your elevation.

The pre made corner detail also makes easy work of these tricky corner sections with a pre cast metal top for a smooth design detail. At the end of the drain must be connected to outlet drainage via the pre designed spigots.

IQ Glass Flush Threshold Corner

See it at the Showroom

The IQ Glass Showroom in Amersham has been designed to showcase the broadest range of architectural glazing possible, all in a real life environment.

A set of our aluminium bi folding doors are used as the main entrance doors to our office which include our flush threshold drain. Visitors walk over this flush threshold and our drain every day without even realising it.

Without a rebate, these bi folding doors require adequate water drainage to ensure that any rainwater is carried away from the threshold of the doors. Our flush threshold drainage detail is the perfect solution for this step-free entranceway.

Contact the team on 01494 722 800 or email hello@iqglassuk.com to organise your own visit to our architectural glazing showroom to see this architectural detail in person.

ASK US ABOUT OUR Flush Threshold Drain for Doors


Commercial use

Flush Threshold Drains for Commercial Projects

Hidden drainage channels by IQ Glass enable a cohesive design aesthetic with sliding glass doors. The large capacity of water the drainage system can handle per minute is astounding and perfect for luxury high-end office or residential apartments with large elevations of glazing and minimal soakaways (permeable ground).

The aluminium drainage channel can also be used around chlorine or saltwater swimming pools because of its anti-corrosive properties and ability to drain away 120 litres of water per minute.

IQ Projects is the specialist commercial division of the IQ Group - www.iqprojectsuk.com

Featured Project

Slim frame sliding glass doors are featured wrapping around the entire 8th Floor penthouse suite of Livingston House. The flush drainage system ensures a cohesive design with the contemporary, architectural sliding glass doors.

The innovative technology enables a large capacity for rainwater with anti-corrosive properties. The flush threshold creates a perfect indoor-outdoor living experience with a seamless transition. 

View this project at our commercial project gallery here. 


Flush Threshold Drain Technical Specification Sheet