Street firms spent the past six months increasing commercial mortgage-backed securitization as investors bought the most debt in six years. That’s now backfiring as banks prepare to market $7.5 billion of loans earmarked to be sold as bonds before credit markets took a dive this month, Bloomberg reports.

Investors are demanding 1.2 percentage points more than the benchmark swap rate to buy new commercial mortgage backed securities tied to shopping malls, skyscrapers, hotels and apartment buildings, according to data compiled by Bloomberg.