"In July, the second charge mortgage market reported its highest monthly new business volumes since October 2008."
The value of new business rose by 17% to £115m compared to the previous year.
In the three months to July, second charge lending rose 18% by value and 20% by volume compared to the same three months in 2018.
In the year to July, the value of new business increased by 15% to £1.18bn and the number of new agreements rose 19% to 26,452 compared to the previous 12 months.
Fiona Hoyle, head of consumer and mortgage finance at the FLA, said: “In July, the second charge mortgage market reported its highest monthly new business volumes since October 2008.
“The popularity of second charge finance is continuing to grow, with consumers increasingly using it to fund property extensions and other home improvements.”