No, I am not sure they were ever officially married as I cannot find a marriage registration for them in Ontario.
They did have 3 children together and were living together as man and wife in 1900 and 1910 in Detroit.
1900 CENSUS - Detroit, Wayne, Michigan
The family were in Michigan since 1893.
William Knapp, head, 44, marr 18 yrs, b Mar 1856 Canada, father born New York, mother born Scotland,
Glorianna Knapp, wife, 44, marr 18 yrs, b Oct 1844 Canada, had 3 children/2 living, born Canada, parents born Scotland
Edgar Knapp, son, age 16, born Jun 1883 Canada, teamster
Frank Knapp, son, age 13, born Sep 1886 Canada, at school
1910 CENSUS - Detroit, Wayne, Michigan
Glorianna is listed as Anna G
1910 United States Federal Census
Name: Anna G Knapp
Age in 1910: 45
Estimated birth year: abt 1865
Birthplace: Canada English
Relation to Head of House: Wife
Father's Birth Place: Scotland
Mother's Birth Place: Scotland
Spouse's name: William J
Home in 1910: Detroit Ward 16, Wayne, Michigan
Marital Status: Married
William J Knapp 45
Anna G Knapp 45
Their son Frank William KNAPP died in 1950 in Michigan, leaving his widow but they never had any children.
Contact me at my email address because I'm wondering if you still have your CLIMIE forum.