Building a Wood Fence – Comon Mistakes to Avoid
You start a fence by making holes spaced about every 8 feet apart for the 4x4x8′ treated posts. These holes should be dug 2 feet deep with a post hole digger. Most people stop right there with a cylinder shaped hole since digging these holes is the most strenuous part of fence building. To ensure the post is well anchored the fence installer should use the post hole digger at an angle around the whole diameter of this hole to make a ball shaped anchor at the bottom of the cylinder. A post hole dug in this manner is much more secure and stable.
Another mistake people make is not realizing the fact that wood never sticks to concrete. Drive by any concrete job and you will notice they use wood forms to frame the concrete held up by nails and wood stakes. The next day the concrete workers take the nails out and these wood forms just fall off of the concrete. Another problem is bugs and water in the soil can deteriorate the wood posts. To prevent these problems the fence builder should put black roof tar on the bottom two feet of the fence post that enters the ground. This will prevent the post from rotting and enables the concrete to stick to the posts.
After the posts are leveled and set you should allow them to dry for one whole day before nailing on them. If you start nailing on them before the concrete is completely set you will knock the posts out of level.
Many people build a fence with only two rails to nail their fence slats to. To build a secure fence that will last for years, three rails should be used. The top rail should be placed on the top of the fence posts lying in a horizontal position. The fence slats should not be installed more than 8″ above this top rail. If so they will tend to twist and turn with age. The bottom rail shouldn’t be more than 8″ above the bottom of the fence slats for the same reason. The center rail should be placed evenly between the top and bottom rails. Although the top rail is placed in the horizontal position the middle and bottom rail should be placed vertically. This will prevent these rails from warping and makes a far better looking and stronger fence.
Ask any roofer about water drainage and he will tell you that water always goes in one direction – and that is down. He is almost correct but he doesn’t understand the lip or linger factor. There is one instance where water can and will travel up, and every fence builder should be aware of. This is also the reason why fascia boards almost always rot and warp.
Have you ever walked by a house with wood siding or a wood fence and noticed the bottom of the painted wood is bubbling and rotten? The paint or wood sealer should have protected the wood from moisture to prevent it from rotting however the installers weren’t aware of the lip or linger factor.
Many contractors never seal the bottom lip of the wood. Over the years as water drains down the face of the wood it lingers on the exposed bottom lip and begins to soak up into the wood causing it to rot. If you want to water seal or paint your new fence, always be certain to coat the top and bottom lip.
