Most condo Declarations will specify what kind of pets are allowed. Gerbils, hamsters, dogs, cats, parakeets, budgies, canaries, parrots and similar kinds of birds, and small fish in an aquarium are generally permitted. Reptiles are usually prohibited as are exotic cats, apes, chickens, etc.
Few townhouse condos have weight restrictions or numbers restrictions on pet species that are allowed. Apartment condos are another matter altogether.
Most new condos do have restrictions on what kinds of pets you can have, and more than a few may have reference in their Declaration disallowing breeds that are deemed to "aggressive" or that may "give the impression of being aggressive".
For example, "Because the presence of certain breeds of dogs or aggressive dogs or dogs which give the impression of being aggressive may give concern to other owners, there shall be no dog allowed on the condominium property (common elements or in units) of the following breeds or types, Pit Bull, Doberman, any sort of guard dog or such other breed as the Committee may determine from time to time is not allowed. It is within the Committee's uncontrolled discretion to determine what breed and what specific dogs are not permitted on the condominium property and its discretion is not subject to being explained or questioned."
That comes right out of the condo Declaration for a particular GTA condo, and that phrasing or very similar appears in at least another 30 or so Declarations for other condos that I know of which were prepared by one particular GTA lawyer who specializes in condo law. Because it is part of the Declaration it is not subject to the usual standard that rules must be reasonable.
Even without such a clause, virtually all condos have Declaration provisions that permit a condo board from declaring any individual pet to be a nuisance and to require the owner to remove it from the condo and owner's unit on demand.
The condo's Declaration is absolute law for a given condo. While some condo boards may not always enforce everything in their Declaration, if they do there is no real way for an owner to fight it as the Declaration provisions are absolute and can be disallowed only if they contravene Ontario or Canadian law.
Nothing in either Canadian or Ontario law gives anyone the right to have unfettered choice of a pet in a shared condo environment. The only possible exemption if a condo bars pets or a specific kind of pet would be if your particular pet was a registered Service Dog for a recognized medical disability. In that case Ontario's Human Rights Code would kick in and overrule the condo's Declaration.
You need to read very carefully the condo's Rules document. You need to read even more carefully the condo's Declaration, specifically the section on Pets that most condo Declarations have these days. That will tell you what is permitted in a given condo.
For any townhouse condo though, I doubt that a Lab would fall afoul of any restrictions unless it was aggressive and likely to pose a biting risk or nuisance barking issue to other residents.
