Did you know that not all chain link fences you see are actually "chain link"? There are actually two popular types of metal fence: chain link fence and welded wire fences. Chain link fences are the traditional fence that you see around: they have strands of wire "woven" together. Welded wire fences look similar, but if you look closely, rather than being woven together they are actually welded at each joint.
Welded Wire Fences Are Stronger
The benefit to a welded wire fence is that it is much stronger than a chain link fence. The welding bonds mean that the fence is essentially a single piece of metal. People are not going to find it easy to break into your home -- and animals are not as liable to break the fence. A direct consequence of this is that welded wire fences tend to be heavier as well. The installation of welded wire also takes longer.
Chain Link Fences Are Easier to Repair
A chain link fence can be repaired in sections. All you need to do is weave a few more lines of chain link in -- something that can be done by anyone without advanced tools -- and you have repaired your chain link. Welded wire fences are not as simple, because they actually do need to be welded to be fixed. A broken welded wire fence is going to require either a professional or someone who already has metal working experience.
Welded Wire Fences Are More Expensive
As a consequence of their durability, welded wire fences are more expensive overall. Not only are they more expensive to construct, but they're also more expensive to install and maintain. On the other hand, chain link fences are by far the most affordable option. Those who have a little more of a budget to spend might want to consider a hardier product.
Chain Link Fences "Bounce Back"
Because they are springy and woven, a chain link fence will generally bounce back. If something puts pressure on it -- such as a large dog -- it will simply snap back into shape. Welded wire fences will not do this; they will usually permanently deform. This makes them more difficult for applications in which they could get bent.
Unless you have significant security issues, chain link fencing is usually the most desirable and versatile type of fence. But there are applications in which welded wire or expanded metal fences could be preferable. A chain link fence contractor will be able to give you more information.