Siparila universal corner 2″ x 3 ½” can be used in both inside and outside corners. Siparila has different solutions for finishing the outside and inside corners. Regardless of the solution you choose, it is recommended that your corner trims are fasted using full round head hot-dipped galvanized nails, minimum length is 2½ “. The nail head must not sink into the wood but sit flush on the surface. One solution is to use 4″, 5” and 6” trims in the corner. All corner trim boards should be installed before the siding and should be attached to the furring strip with nails. Remember that nail heads must be painted with Siparila Topcoat® touch-up paint.