"These figures provide reassurance the economy is being better balance and likely to be sustained," Samuel Tombs, U.K. economist at Capital Economics, told CNBC.
The pickup in business investment was confirmed by U.K. CEOs, who told CNBC they were seeing signs of a turnaround in their sectors.
"Construction and building really got hit hard in the downturn. And I think it has now stabilized with signs that it could start to grow," John Carter, CEO of building material supplier Travis Perkins, said on Wednesday.
"We feel we are going to get on our front foot now, and start to expand our network… and grow our business."
His comments came after data released earlier this month revealed that construction output rose 0.2 in the final three months of 2013. This followed a 2.6 percent upswing in the previous quarter, as government mortgage schemes boosted demand for housing – although this has fueled some fears of a property bubble.
(Read more: Bubble alert? UK house prices rise to 6-year record)
The rosy economic picture goes beyond construction, according to a new study from PwC, which said it is being felt across U.K. private businesses.
Over half of the 421 U.K. private business leaders surveyed agree that the positive economic news reflected their current experience, with 38 percent saying they intended to hire new staff this year.
"On balance, the U.K.'s private business leaders are positive about prospects for the year ahead," PwC partner Stephanie Hyde said in a statement.
"There are patches of good growth across the U.K., despite many businesses still dealing with tough trading conditions and the demands of adaptation."
(Read more: UK's Osborne promises budget of 'hard truths' to balance economy)