Final answer:
The 'bleed-out' when torch applying IKO SBS membrane refers to the bitumen that emerges from the seams to create a seal, ensuring the layers bond correctly and prevent leaks.
Step-by-step explanation:
The question pertains to the installation of IKO SBS membrane, a type of modified bitumen roofing commonly used in commercial roofing applications. When torch applying IKO SBS membrane, the desired 'bleed-out' refers to the small amount of bitumen that should exude from the seams of the material after the two layers are heated and pressed together. This bleed-out is essential for creating a proper seal and ensuring that the seams are completely bonded, which helps in preventing leaks.