The UK’s last remaining strict leather and rubber fetish gay club has been saved after a London council blocked plans to redevelop the East End site into a 12-storey residential tower.

Tower Hamlets ruled against the proposed 46-flat development on Mile End Road because it would “harm the long-term provision of a nightclub that serves the LGBT+ community”.

Cllr Rachel Blake, the borough’s deputy mayor, said the council viewed the 34-year-old Backstreet bar as “an important community asset” and was “going the extra mile… to protect safe spaces for our diverse community”.

“It is the last true gay fetish club, and diversity matters to us,” she said. “This kind of venue really matters to us, it matters to Tower Hamlets and to the whole of London. It is very important to have safe spaces for the whole community.”

Dozens of men who regularly visit the Backstreet, which boasts the “strictest fetish dress code in Europe”, wrote to the council during the six-year planning battle to explain the importance of the club to them.

“When I discovered the fetish scene by going to the Backstreet as an 18-year-old, it saved my life,” one man wrote. “It gave me a community that made me feel welcome, and embraced me flaws and all. It stopped me thinking I was odd or an outsider, [it] gave me confidence in myself, and gave me some incredible friends and mentors.”

It’s a real time warp, that hasn’t been updated since the 80s, with boots and whips hanging from the ceiling

Oscar, who at 21 is much younger than the Backstreet’s average clientele, said he would be gutted if the club closed as it was his favourite place on earth, and he “saved like crazy for [his] leather gear”.

On his first visit, Oscar, who works in the arts, dashed from an Uber cab to the venue’s nondescript black doors so as not to be spotted by members of the public in his head-to-toe leather outfit. “But when I got to the door I realised it was cash only, and I had only cards,” he said. “So I had to walk to the cash machine. But it was good, it made me more confident.”

Now Oscar goes to the club about once a month and is starting to feel like part of the community. “It’s a real time warp that hasn’t been updated since the 80s, with boots and whips hanging from the ceiling,” he said. “People say: ‘Don’t you find it really scary?’ But actually it’s a really warm, friendly and sociable space.

“It’s nice that we have a place that we can go without judgment. I know that I’m not going to be heckled for what I wear and what I do, which might happen in a regular gay venue.

“I had my 21st birthday party in there, but I’m by far the youngest person who goes there. Most of the people are in their 30s to 40s, and there are some in their 50s to 60s. What other gay bar do you get that in? It’s a really nice thing.”

Blake, who is also the council’s cabinet member for planning, said London had lost a “staggering number” of LGBT nightclubs over the past decade, with Tower Hamlets “particularly badly hit with the loss of 73% of LGBT venues since 2006”. Eleven London boroughs, including Haringey, and Kensington and Chelsea, have lost all their LGBT bars, according to research by University College London.

It is the second time Tower Hamlets has made planning rulings to protect an LGBT venue. In 2017 the council ruled that the redevelopment of the Joiners Arms bar on Hackney Road could go ahead only if the new building contained a similar-sized gay bar.

Blake said saving the Backstreet was more important than saving a standard gay bar because it served “a particular niche of the community”. “When there is a rise in hate crime, we must stand up for those with all backgrounds, and it is important that people can enjoy themselves in a safe space without external judgment.”

Homophobic and transphobic hate crimes in England and Wales increased by 144% over five years to 11,600 in 2017-18, Guardian analysis has shown.

Tower Hamlets blocked the proposed housing scheme even though the developer, a subsidiary of Galliard Homes, had promised to preserve the Backstreet in the basement of the new tower, and pay £22,500 to move and store the club’s collection of fetish equipment, including boots, whips, rubber and gas masks.

Queer today, gone tomorrow: the fight to save LGBT nightlife Read more

Blake said councillors worried that putting the club in the basement of a residential building would have led to its demise. “So much of my inbox is noise complaints,” she said. “The reality is noise would have led to its closure.”

In the ruling against the development, the planning inspector Julia Gregory said: “I am also not convinced that the nightclub would be well received by parents with young children living above … or would be considered a benefit by future residents.” Gregory said she was therefore not satisfied that the future of the club was protected. A spokeswoman for Galliard declined to comment.

Nigel Whitfield, a Backstreet regular and director of the Breeches and Leather Uniform Fanclub which has led much of the campaigning against the development, said it was “flabbergasting” that Tower Hamlets council had spent so much time listening to club regulars’ concerns. “It is simply unimaginable that 20 years ago a council officer would write reams of pages in defence of a leather nightclub,” he said.