The proportion of households living in the Private Rented Sector (PRS) will rise to 24% over the next four years, according to new research.
Knight Frank's Multihousing Report suggests some 5.79 million households will be private renters by the end of 2021.
A significant survey of over 10,000 tenants reveals that the majority (68%) expect to still be living in the PRS in three years' time.
What's more, the young professional demographic - 25-34-year-olds - makes up the largest proportion of private renters.
Tenants' biggest concern is affordability, followed by location and then the rental property itself.
“The flexibility that renting offers has reinforced its popularity as both a sensible and accepted solution for young couples without children and those living on their own but also highlights an expected rise in older households over the next five years,” says Tim Hyatt, Knight Frank’s head of residential lettings.
"The number of people renting out of choice rather than due to affordability of ownership constraints is an interesting indicator of how the market will continue to thrive in terms of tenant demand.”
The property firm's research also suggests that institutional investment in the PRS is set to soar to the tune of £70 billion over the next five years.
It says that a raft of changes in recent years - including the 3% stamp duty surcharge and the restriction of buy-to-let mortgage interest tax relief - have made institutional, large-scale investment in the PRS more appealing.
The Build to Rent market in the UK is currently worth around £25 billion - Knight Frank estimates that will grow by an additional £45 billion between now and 2022.
The Multihousing Report also includes a survey of major Build to Rent investors. A key finding is that 65% of investment is in London and 15% of all residential units currently under construction in the capital are for Build to Rent, compared to 4% across England and Wales.
James Mannix, head of residential capital markets at Knight Frank, comments: "As consumer demand for affordable, flexible accommodation continues to rise, the PRS is firmly establishing itself as a key opportunity for institutional grade investment, due to its long-term potential."
“In order to enhance Build to Rent specifically, the main hurdles of planning policy and land supply must be addressed. With both issues being recognised in the recent housing white paper, we hope to see the government encourage more Build to Rent and help to better identify developable land.”
Last week, Legal & General announced that its Build to Rent scheme in Salford is the first to start welcoming tenants.