Fence Panels can be pre-fabricated, as in the case of vinyl and ornamental aluminum, or can be made from boards and rails like the picket fence below. Most panels are either 6 ft. or 8 ft. long depending on the material. Longer than 8 ft. and the panel will sag under its own weight. Any shorter and it would require additional posts and hardware, which would add to the expense.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgvrOiqu9F9qvHJnIMwD0_Qg5bSRGuEYjf0hjWr0ciUKOG2QlZGiwPlP29d81zPDmzeYyZFVGAMezLIyhABodqo-yBUT3rUfM_11AnityQTyO3tC-ENY25qMPh0nRpLAdWCrdsFmwtzmmc/s400/picket-fence-c.jpg)
Most Fences have 2 or more panels anchored and connected by posts.