On houseboats, shade may be provided by either bimini tops, which typically can be folded out of the way when not needed or desired, or by full awnings, which are typically larger, more permanent structures and covers.  The galleries here show all of these options, including full enclosures as well.

Bimini Tops on Houseboats

 Awnings on Houseboats

Full Enclosures for Houseboats