cladding

Short definition from Wiktionary

Noun

1. 1
   Clothing; clothes.
2. 2
   Any hard coating, bonded onto the outside of something to add protection, such as the plastic sheath around an optical fibre.
3. 3
   A weatherproof, insulating or decorative covering fixed to the outside of a building.

Verb

1. 1
   present participle and gerund of clad