If you own a house, good news! If you don't, you may want to go read about kittens for a bit

House prices are set to rise by almost 20% in the next five years.

Photograph: Getty Images

Savills, the luxury estate agent, has revised upwards its estimates for the growth in house prices over the next five years. The firm now expects UK house prices to average 18.1 per cent growth over the period, up from the 11.5 percent in the original forecasts published in November.

A significant chunk of the increase comes from Savills' changed forecast for this year. The company had predicted a rise of just 0.5 per cent, but now expects prices to grow by 3.5 per cent over 2013 alone. It cites the government's "Help to Buy" policy, which subsidises purchases of newly built homes, for the changes.

Lucian Cook, the director of of Savills residential research, explains:

A combination of low interest rates and stimulus measures means there is capacity for improved price growth over the next three years or so. But it comes at the price of later price growth in 2016/17 when interest rates are expected to start rising. Overall, this means that on an inflation-adjusted basis our revised forecasts indicate that prices will increase by just 2.3% over the next five years.

Help to Buy goes further than any of its predecessors in being aimed at all buyers, not just first time buyers, but we believe its primary impact will be increased transaction levels and that higher than expected price growth is a secondary impact. It needs to be considered against the context that the market remains only partially functioning. While the combined package of Help to Buy measures could add 400,000 transactions over the next three years or so, they would still remain 24 per cent below pre crunch levels.

Cook also dismisses concerns that Help to Buy could provoke a second house price bubble, arguing that the conditions which the scheme imposes prevents that. Moreover, he points out that "rising market activity has been due to increased turnover of existing debt rather than the creation of new debt that defined the late nineties/early noughties market".

That's a bittersweet caveat, however. What it means is that people already on the housing ladder are starting to buy and sell again – but that people who don't currently own a house (or, more specifically, have a mortgage) aren't getting a foot on the first rung.

Despite Help to Buy's name, the policy represents a decreased focus on first-time buyers from its predecessor, FirstBuy. To be eligible for that programme, you had to be a first-time buyer. That ensured it targeted its aid, but also led to it being a failure in the grand scheme of things, spurring the construction of just 6,493 homes as of February this year. Help to Buy, by contrast, is open to anyone buying a new build worth under £600,000.

The purported value to people not on the property ladder of the scheme is indirect. By subsidising purchases of new houses, it ought to incentivise housebuilding, which, in the long run, is what we need to get house prices down to a sensible level. But in the short term, it seems to just be boosting the price of homes which were going to be built anyway. That's good for the developers – and good for the lucky holders of subsidised mortgages – but does little to calm the fear that propertyless people have that they may never get on the ladder.