Wikipedia divides the spelling geographically: mold (US / CA) or mould (UK / NZ / AU / ZA / IN / CA). We are in Victoria, B.C. but most of Canada falls somewhere in the middle. Traditionally Canadian environmental consultants have always used the British spelling (and still do), although mold is becoming much more common in many publications. We can provide options and pricing for asbestos removal. We try to use the language of our customers and when we ask people which version of the word they use, and research what people are searching for on Google, it appears they predominately use the US version “Mold”.
Mold, Mould, & Google
Interestingly, if I search for the term “mold removal” or “mould removal” on Google.ca or Google.com I see roughly twice the number of search results for the US spelling.
British English has no “mold”, and American English has no “mould”. The word referring to the various funguses that grow on organic matter (or a frame for shaping something) is spelled the same in both uses, and the spelling depends on the variety of English. Canadian and Australian English favor the British spelling, though mold can be fairly common in Canadian publications.