BongJun 5, 2016, 23:0806/05/1605/02/163How does one use upgrade sketchesOnce one has an upgrade sketch how does one use it to upgrade a building.
Alyona KolomiitsevaCommunity ManagerJun 6, 2016, 10:4106/06/1609/17/158278Enter the Building and press Upgrade. Available Sketches will be deducted automatically.
BongJun 29, 2016, 15:0706/29/1605/02/163There is no option to use upgrade sketches when one enters a building.
Thomas BrunsonJun 29, 2016, 17:3906/29/1603/22/161289The one detail omitted is the building normally has to be level 20 or above before using sketches, except the Infirmary to get above level 13.