No doubt you think Miranda Seymour-Smith's a bit quixotic. After all, she wants to get women onto site by banning wet T-shirt jokes. On the other hand, the Queen asks to come to her dos and Peter Rogers is her biggest fan. Still so sure?
Miranda Seymour-Smith looks too small and feminine to make herself heard in the blokeish construction industry. But this diminutive, softly spoken woman is ready for a fight. As chief executive of Women's Education in Building, a charity that trains women for jobs in construction, she is planning to challenge the deep-rooted preconception that women aren't welcome on site.

Her chances of succeeding, you may think, are as tiny as she is. After all, women provide only 9% of the construction workforce and 1% of tradespeople. Worse still, only 3% of trainees entering craft and technical construction courses are women – so the sex balance is unlikely to shift in the near future.

Her job is made even harder by the fact that her background is not in construction, but in adult education. So Seymour-Smith will have to use some unusual tactics in the battle against building-site sexism.

She will draw on 17 years of experience in local authority adult learning where, after graduating with a degree in European studies, French and linguistics, she started by teaching English and basic communication skills to the unemployed. It is here she says she developed a passion for equality and an ability to communicate. And she hopes these skills will help win support from the brashest site managers.

But why, given her background, has she set her sights on shaking up the construction industry? "I am interested in how women can take a bit more responsibility for being involved in the construction of the built environment," she says.

This is Seymour-Smith's second stint in charge of WEB – she stepped in as acting chief executive in 1996 while her predecessor was on maternity leave. This experience shaped her interest in the building industry. "I got very interested as to why there aren't many women in construction. I met with employers and found that this issue embarrassed them too. But nobody knew how to change it because there isn't a simple answer."

She went back to the world of adult education, but stayed in touch with WEB as a consultant until returning full-time six months ago.

She is already making an impression. On 11 March – the day after Building goes to press – WEB is to celebrate its 20th birthday with a Charter aimed at encouraging employers to hire more women. And, in a coup for Seymour-Smith, the event will be attended by the Queen and Princess Anne, WEB's patron, who has agreed to extend her patronage of the charity for a further five years.

Amazingly, says Seymour-Smith, the Queen asked if she could come and visit, rather than the other way round. According to a spokesperson for Buckingham Palace: "The Queen heard about WEB through the Princess Royal and she was hugely impressed by what the organisation is doing. She has a certain interest in women achievers."

The real test for Seymour-Smith will come after the brouhaha surrounding the Queen's visit has quietened down. Does she really have what it takes to bring about changes in one of the UK's most enduringly male domains?

Encouragingly, she has already won heavyweight support from the industry in the form of Peter Rogers, technical director of Stanhope.

If after our relaunch more employers don’t come on board, then maybe we will think about naming and shaming them

"I think she is brilliant and I see her as the catalyst for change in the industry," he says. "We need to get away from this macho image of building sites being big, brash and dirty. Women bring a more natural balance and in many cases they prove themselves better than their male equivalents."

Rogers has pledged to become a fully paid-up member of WEB and he has asked all Stanhope's contractors to follow his lead – a move that will bring a much-needed financial boost to the organisation.

WEB runs on a tightly managed annual budget of £3.4m. The money comes from a variety of central sources such as the Learning and Skills Council and the single regeneration budget. And the charity has a remarkably high success rate – virtually every one of its 300 trainees leaves with a qualification.

But for Seymour-Smith to make a lasting impact on the construction industry, she knows that she has some big hurdles to jump. "Construction is a men-only environment. It is in a bit of a bubble and therefore it is not a balanced place," she says. "People have to realise, for things to change, that they can't even make wet T-shirt jokes on site because that will stop women coming into the industry."

She believes attitudes are already beginning to soften. "I have noticed an enormous willingness among employers to find out how to crack this very difficult thing of getting more women into the industry," she says.

Encouraging words are all very well, but Seymour-Smith faces more practical challenges. Changes such as improving site facilities so they are more acceptable to women could be costly.

But worthwhile. "The construction industry faces skills shortages and skills gaps. It needs to recruit good, willing workers," says Seymour-Smith.

She adds that the presence of women on site can be very beneficial. "Immediately there are women on site, a different kind of attention is paid to health and safety issues. I have even had reports that the men become more conscious about their behaviour. It just has a real effect."

In Seymour-Smith's spartan office, squeezed under London's busy A40 Westway, it is sometimes hard to imagine that she is sufficiently steely to take on the macho world of building. Even the constant roar of the traffic overhead threatens to drown out her ideas before she has had a chance to implement them.

But firms should not be complacent. "If after our relaunch more employers don't come on board, then maybe we will think about naming and shaming them," she says. While the words are delivered in her usual easygoing style, with a mischievous smile thrown in, you get the impression she is much tougher than she looks.