Today marks the deadline for businesses to submit a report with their gender pay gap figures, which has since revealed that the average pay gap in the UK is 18.4% in favour of men.

The gender pay gap is not the same as having unequal pay, which would be against the law. By law, men and women with the same jobs have to be paid the same wages. A gender pay gap can arise if there are more highly-paid men than women in a company, if women are seen to be less experienced than their male counterparts, or if women take a hit to their salary after taking maternity leave.

In reporting gender pay, firms with more than 250 staff have to publish data on the average difference between male and female employees.

With a focus on the DIY, home improvement and garden industry, analysis from the government findings suggest the gender pay gap is larger than expected. For instance, B&Q reports that women's mean hourly rate is 8.8% lower than men's, and the median hourly rate is 2% lower. Further findings from the report show that across all four quartiles in B&Q men have a higher representation, with the highest paid positions in the company are largely taken by men, showing only 38.3% of them to be female.

B&Q said in its report: "This analysis shows that our gender pay gap is driven by a lower level of female representation in senior roles within the company."

Wyevale Garden Centre has reported women's mean hourly rate is 16% lower than men's, however the median hourly rate is 0% showing that men and women earn the same. Across pay quartiles, Wyevale Garden Centre has shown a much larger representation of women in the business, with women in a higher percentage over men, apart from the highest quartile which is the senior positions of the company which highlight that 48.8% of these positions are taken by women.

What are the consequences of not publishing your findings?

Rebecca Hilsenrath is chief executive of the Equality and Human Rights Commission (EHRC), which can prosecute large companies that have not reported their gender pay gap details.

"We're looking at approximately 1,500 companies which haven't reported," Ms Hilsenrth told the BBC.

"We're obviously pleased with the rate of reporting, but it is the law, it's not an option. It is the right thing to do, and we will be enforcing against all those organisations which failed to meet the deadline."

In practice, this would mean a statutory investigation process, she said.

The EHRC will be sending letters to all of those organisations on Monday. They will then have 28 days to respond. Terms of reference will then be issued for the enforcement process, which will be made public.

"This is going to be a very public affair. It will impact quite considerably on members of the public, people who work for them, and you'll see a growing backlash against people who aren't complying," she said.

A detailed report of the gender pay gap in the DIY, home improvement and garden centre industry will be featured in our May 11 issue of DIY Week.