12 letters

meetinghouse ∙ westinghouse chapterhouse ∙ charterhouse customshouse ∙ draughthouse flickermouse Flittermouse ∙

13 letters

perimenopause ∙ Postmenopause entrepreneuse ∙ blanchisseuse ∙ boardinghouse ∙ clearinghouse ∙ countinghouse ∙

14 letters

slaughterhouse ∙

15 letters

Pseudomenopause

Words with a ∙ are valid Scrabble words (SOWPODS word list)