“We were talking about the project and came up with this idea of having door-sized canvases with old poems written on them,” says Roger McGough.

“But after about three pints we decided to have doors as canvases.” It is at such points in an evening that inspiration is most frequently forthcoming, I suggest, and Roger McGough laughs.

Most of the doors here are, indeed, canvases for Roger McGough’s witticisms and poetry. He’s a hard man to pin down – with children’s poetry, music, theatre adaptations in Tartuffe and assorted media among his body of work.

His wordplay and lexical dexterity are famed. But McGough is not simply a man of funny words. He has been a front-runner, twice, for the position of poet laureate and is currently President of the Poetry Society. He’s seriously good, if not always totally serious. Perhaps it is better to sum him up by saying that he is a very clever man.

And McGough, along with book binder and artist Mark Cockram and students from Liverpool John Moores, has created a delightful installation at the Museum of Liverpool in the shape of Liverpool Doors. It’s a funny, warm, clever and engaging corner of a museum that, dare we say it, needs an offbeat element.

“Some of the doors have resonance and some were simply sent in by people,” explains McGough.

Among the doors are examples from Bold Street curry house Asha, a door from sculptor Arthur Dooley’s studio, the Trophy Room door from Anfield and a turnstile door from Goodison, a door from Myrtle Street’s old art college (with Museum of Liverpool employee Linda Pinewood’s name on it) and doors from the Everyman and Everyman bistro.

“I wanted the people of Liverpool to be represented too, so we’ve got the Liverpool Saga (a lengthy poem written by the people of Liverpool for 2008, bookended by McGough’s words) at the end of this barricade of doors, mounted on doors from the Everyman,” says Roger as we pass a small painting of a clergyman with a glowing hat on, a recent addition. It’s called Arch Beacon.

“It’s about verbalising the visual and visualising the verbal.”

There are so many details to take in and to mull over that every door in the installation needs consideration. Some, like satisfying puzzles, only reveal their mysteries and pay-offs after a few moments of thought. Liverpool Doors truly does reward an investment of time and effort, something its creator has clearly thought about.

“I read something fascinating recently; apparently people who go to art galleries only spend an average of 2.5 seconds looking at each work of art. I’m hoping people are drawn to the riddles and the motifs here.”

McGough is clearly enthused by the project, as is co-creator Mark Cockram, who created the physical Liverpool Saga book on display as part of Liverpool Doors.

“It’s very satisfying for me, working the way I do, to see the finished product. I think of them as pages of a book; phonetics, diptychs, triptychs, politics,” he adds, with what sounds like the start of an impromptu spot of rhyming.

The ambiguity of what a door can represent is alluring, and Cockram is clearly excited by the potential for viewers to project onto the Liverpool Doors their own thoughts and feelings.

“There are so many sayings about doors: closed doors, early doors, locked doors. And they can mean security or insecurity.

“With the regeneration in Liverpool a lot of doors are being thrown away, used to line skips or to barricade houses; they’re little pieces of history.”

They are indeed. As an object both physical and metaphysical they’re intrinsically ambiguous and, because of that, they’re instantly fascinating. A gateway to another world. Or, more prosaically, the entry to the downstairs loo, toilet duck and Andrex.

Doors are fascinating in their own right; a little time capsule of a house or public building, whose interiors may have changed time and time again while the door survives intact. A door in the exhibition has been left totally untouched; a mural of Madonna and ancient sun-bleached stickers tell of a child’s bedroom, unchanged for perhaps 25 years.

Everything at Liverpool Doors is worth examining, chiefly because they’re covered in little McGough asides or witticisms, but there’s a lot more to them beyond that. Little reflections on Liverpool life and a physical representation of the different paths our life can take, simply by stepping from one door to another.

Just as I’m leaving Cockram comes over with a hinge, opening and closing it. “Look,” he says, “it’s like a book.” It is too.

“This guy’s been feeding me angles all night,” I say to no-one in particular, stupidly pleased with a rare crumb of wit. Cockram laughs generously.

But Roger McGough hasn’t heard what what may be the sharpest bit of wordplay I’ll come out with in my whole life. He’s pondering where to put another arrow in a door called Objet Dart.