As we have done in the past, we have opened up this call to the public and are doing a webcast. The webcast can be accessed at www.lpcorp.com. Additionally, to help with the discussion, we have provided a presentation with supplemental information that should be reviewed in conjunction with the earnings release. I'll be referencing these slides in my comments this morning. We have also filed an 8-K this morning with some supplemental information as well as our second quarter 10-Q.
I want to remind all the participants about the forward-looking statements comments on Slide 2 of the presentation. Please also be aware of the discussion of our use of non-GAAP financial information included on Slide 3 of the presentation. The appendix attached to the presentation has some of the necessary reconciliation that been supplemental -- been supplemented by the form 8-K filing we made this morning. Rather than reading these 2 statements, I incorporate them with this reference.
Before I get started on the detailed discussion of LP's financial results for the second quarter, I would like to summarize our successful debt refinancing. We strengthened our balance sheet during the quarter by issuing $350 million, a new unsecured bond with a 7.5% interest rate and an 8-year maturity. The majority of the proceeds were used to refinance our 13% bond which had a 2017 maturity date. As a reminder, due to the discounted nature of that bond, the effective interest rate was slightly higher than 19%.
In addition to replacing the secured debt with unsecured debt, we added approximately $100 million to the balance sheet while reducing annual cash interest expense by $5.4 million, and the annual book interest expense by over $13 million. The offering was well received in the market, and we are pleased to end the quarter with a stronger balance sheet and lower interest cost.