In The Studio: Ryan Gander, artist

'We do not sit down here to come up with ideas. Ideas come in the car'

Whether you love or hate conceptual artist Ryan Gander's work, it is always challenging, posing deliberate questions to the viewer. His piece Airflow-velocity Study for I Need Some Meaning I Can Memorise (the Invisible Pull) in dOCUMENTA (13), now open in Kassel, "occupies" the most prime bit of real estate, the ground floor of the Kunsthalle Fridericianum. "Occupies" in the most intangible sense, that is, as there is nothing for the viewer to see, only a prevailing breeze that is intended, he says, "to pull people into the space". The work "questions expectations", explains Gander, and took five years of expensive engineering to develop. The empty space was important, he says, as it "puts values into question: use, function, and cost. And how a large footprint is being consumed for little ideas."

Gander, who is in a wheelchair, divides his week equally between two studios, one in his home in Suffolk and one, where we are today, in an industrial mews in Hoxton, east London. He calls the London studio a "semi-public space" where he and several assistants "sort out what needs doing". "We do not sit down here to come up with ideas," he says half-seriously. "Ideas come in the car or when you're not expecting them. It is probably five days a year when I decide what to make." The rest is engineering it. "Introducing stuff into the world takes so long, the logistics take so much time."

The studio is an adaptable space where some things are fabricated and worked on. I am given a demonstration when I am invited into a small room off the back, where a temporary sound studio has been installed, and am invited to record a small passage for a work to be shown in the Palais de Tokyo in Paris this autumn.

On the end wall of the studio is Self Portrait, June, a work consisting of a series of glass palettes. Gander says, "I paint myself every day but I don't show the portraits, I only show the palette. I'd have to kill you if you saw the portrait as you would know how bad a painter I am'. It is a discipline for him, as he admits he is "not a massive fan of painting", but this is conceptual work. Gander says it is "nice to have missing bits as it allows the viewer to imagine their own painting".

I have occasionally tussled with understanding Gander's work, and I remind him of the tension of our previous meetings. "If I hand it to you on a silver platter you won't like it,' he says. "You can choose to engage or not. By leaving blanks there is room for you."

Ryan Gander: The Fallout of Living, Lisson Gallery, London NW1 (020 7724 2739) to 25 August