1. Dear Rodney, if you wish to object, you need to formally write to the Planning authority enclosing your objection and stating the grounds for it. Essentially, your basis for objection here is that by granting planning permission, the Planning authority would be licensing a trespass. This is because if there is an overhang into your property by your neighbour's roof, this constitutes a trespass in law. Not only do you own the land on which your property is built but your also own the air above your property. So, if your neighbour's extension overhangs your boundary, this constitutes a trespass in law.
2. If you wish to object, you need to formally write to the planning authority and enclose your grounds of objection. It is not sufficient to simply speak with the planning officer. So do write.
3. Essentially, you don't want the planning authority to grant planning permission where there is a trespass involved.
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