Question: Is there one word that includes walls, ceiling, floor - basically all the faces of a building?

For example I would like to use such a word in the following sentence: 

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> "All the X of this building are made of wood".
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Answer: 
If you want to refer to what is *inside* the walls, ceiling and floor, you can use **framing**.

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> The framing of this house is all wood.
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> 
> 

While there is no single word that includes the surface, you express this by saying

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> This house is all steel framing covered with drywall.
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> 
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There is no English word to cover this. As has been suggested, structural surfaces is as good as anything.