You need to have a permit. And, you need to find out the fence regulations from your city hall. Most cities regulate the height, type of fence, etc. I, also, suggest you hire a surveyor. I have a current listing, where the owner wanted to put up a fence to make the home more desirable. I suggested that he hire a surveyor. He said he knew where the property lines where, so that was not necessary. After the fence was installed, the next door neighbor called me to inform me that the fence encroached on her property. She had a survey done. So, my client needed a surveyor. And, yes, his fence encroached on the neighbor's property.