September 19, 2014

To: All Mechanical Insulation Customers

RE: November-December Downtime on Unit 91 in Cleburne, TX

As part of our commitment to keep you updated on any upcoming issues that may impact your business, we want to advise you of some planned maintenance downtime on Unit 91 at our Cleburne, TX manufacturing plant. The maintenance will affect our line from November 10, 2014 to December 19, 2014.

We are building inventory to service your business during this outage period. Also, we are currently in the process of conducting a SKU level audit to ensure we have the correct mix of inventory. But as an added level of precaution, we request that you review and communicate back to your JM Representative any special projects you may have as well as any anticipated changes in your order patterns, product mix or requirements that may exceed your normal volume. Additionally we request that all made-to- order items that need to ship on or before December 29 be placed no later than October 20, 2014.

Mechanical products manufactured on Unit 91 include: Mat-Faced Micro-Aire® SuperDuct® RC Diffuser Board LP Board Permacote® Linacoustic® R-300 Spiracoustic PlusTM 800 Series Spin-Glas® 1000 Series Spin-Glas® Precipitator Spin-Glas® Incombustible Hullboard Fabrication Board®

Thank you for your ongoing support of Johns Manville.

Dave Skelly Director of Sales Performance Materials