In a survey, 59% of women say they regularly stand in line for the loo, compared with 11% of men – the result of gender bias in architecture and design, plus a dose of prejudice and taboo

Have you ever been queueing to use a toilet when some woman has started banging on about potty parity? That was me. It makes the time spent waiting pass more quickly, but it also educates any men in earshot who think that the long lines of women are caused because we can’t do our business efficiently.

In fact, the queues are a result of centuries of gender bias in architecture and design, plus a dose of prejudice and taboo. Studies show that women take twice as long to use a toilet as men: about 90 seconds for women, 40 seconds for men.

In a new survey, 59% of women said they regularly have to queue, compared with 11% of men. This makes sense: women usually have more clothes, more bags and sometimes (more often than men) small children to deal with. We also use toilets more frequently, as we need to change sanitary products. Most architects provide men’s and women’s toilet areas of equal size and capacity when, to reduce queues, women would need a third more cubicles as men to account for the extra time.

Potty parity is an American movement that has done good things in educating architects, perhaps because women in the House of Representatives were not provided with toilets near the voting floor until 2011. Before that, they had a long trek.

What is the solution? Unisex toilets have been touted ever since one featured in Ally McBeal with equal billing to Calista Flockhart. I don’t like them on two grounds. I would rather share a public toilet with the cleaner sex (don’t protest, men, until you get better at washing your hands). And as women’s safe spaces are being reduced all over the country – fewer refuges, less funding – I am in favour of preservation not neutralisation. Female funnels, so we can pee standing up? No thanks (whoever thought them up has clearly never worn Lycra shorts).

An old Indian story tells the tale of Birubar, who, to persuade his master of the necessity of toilets, arranged a trip on a boat that had none. By the end of the day, the master was persuaded. I am not suggesting sending male architects on a day trip with no loos, although it’s an idea. But protest would be better than waiting silently in yet another queue because toilets are thought of as unspeakable.