Extra tram services across Melbourne will cause a rift between the have and the have-not suburbs, experts say, and will benefit those already lucky enough to live on the tram line.

Yarra Trams will increase services along St Kilda Road and to the north-west of the city to pick up the slack during the Metro Tunnel construction, set to be completed in 2025.

While new tram services were a good thing, the suburbs that would benefit already had great access to public transport, Wakelin Property Advisory director Paul Nugent said.

“It actually compounds the benefits of living in already well-serviced areas,” Mr Nugent said. “What it potentially could do is further polarise desirability of certain locations and create stronger demand for properties in the inner areas.”

Property prices tended to be higher in inner and middle suburbs with access to trams and trains. Suburbs including Glen Iris, South Melbourne and Malvern, which will benefit from the new services, each had median house prices of more than $1.2 million.

Suburbs in the west without train or tram access, including Sunshine West and Braybrook, had much lower medians – most between $600,000 and $700,000.

Mr Nugent said though public transport access was not the only thing that affected house prices, suburbs in the west could be given a more level playing field with improved bus services and, eventually, more train and tram lines.

“Melbourne’s transport network is a bit like a spider’s web that’s gone out from the centre of the city and the radial connections have always been relatively weak,” he said.

Victorian Greens transport spokesman Sam Hibbins said the extra services were welcome, and were needed regardless of the Metro Tunnel works.

“The issue with the inner city transport is the overcrowding,” Mr Hibbins said. “I would question the idea that just because the inner city gets something it inherently takes away from the outer suburbs.”

He said a holistic approach to public transport was needed, and both the inner and outer suburbs needed better, more frequent services.

University of Melbourne urban planning lecturer and transport expert Crystal Legacy said buses could provide more connectivity between homes, train stations and tram stops in Melbourne’s outer suburbs.

“Quality services provided using buses can often be used to reach parts of the city that aren’t currently being serviced by trains and trams,” Dr Legacy said. “It’s something that we don’t do very well, and there hasn’t been a lot of emphasis on that.”

She said Melburnians had a culture of either driving or using the tram or train, mainly because buses were unreliable, and did not connect them with other forms of transport.

“We see cities around the world which have high-quality public transport and bus services into these areas that then feed into the tram and train line – which act as our bones – and buses act as our nervous system.”

Mr Hibbins said increasing services city wide would be an easy first step, and would need to be supported by building infrastructure to cover traditionally public transport-weak areas.

“Particularly along the Melton line, you’ve got areas with rapid growth with inadequate train services or none whatsoever,” Mr Hibbins said. “They’re either locked into car dependence or having to deal with completely inadequate public transport.”

Transport Minister Jacinta Allan said the Metro Tunnel would deliver more train services to the west.

“It will free up space on the network for an additional 113,000 peak passengers every week on the Sunbury line and an additional 63,000 peak passengers every week on the Werribee/Williamstown lines,” Ms Allan said.

She said there was also potential for tram service to be rerouted to the city’s west, as the tunnel would take pressure off the St Kilda Road-Swanston Street corridor.