Are there any bylaws preventing a neighbour from erecting a temporary garage kit (canvas and steel poles), which obstructs my view of the lake?
Potentially, yes—but it depends on your municipality. Local bylaw officers, or officials with your building and planning department, are the only ones who know for sure, so consult them, or check online: Often, bylaws are posted on the website.
The specifics of the situation—for example, how this neighbour’s property is zoned, how large the “garage” is, or where on the property it’s located—may make a difference. Temporary structures such as these fabric-and-pole jobs are usually considered “tents” under the Ontario Building Code. Tents don’t need building permits, provided they comply with a few rules (they can’t be larger than 60 square metres, for example). But every municipality has zoning bylaws about location, lot coverage, and height. And some tents still may require special approval or a specific temporary tent permit.