Our projectors are guaranteed to work at top quality for 625 sq ft. The farther it is from the intended surface more is the coverage area, but also the effect will be diluted. For example if you place the Star Shower at a distance of 10 ft the coverage will be 200 sq ft if you place the Star Shower at a distance of 40 ft you get 3200 sq ft, but with a different intensity. The farther away from the projector the object is, the bigger the dots get. You can adjust the light out further from you house to get the coverage you need or consider getting an additional snowflake projector.