Question
Trying to gather information about building a fence.  First should I use concrete or dirt to secure posts? I was at Home Depot looking at cost of concrete and the charts on bag said for 30" post in ground and 4" diameter I'll need 4 bags of mix - seems like alot and can be costly considering I will have about 15 post going in.  Should the post be 30" or 36" underground and will I need that much concrete?  Is tamping dirt a good alternative and if so is there another tool besides a expensive tamper to use to compact dirt? Also can I use a laser level vs post level to ensure posts are aligned properly? Thanks for your feedback.

Answer
Hey, Eric.

Your fence will last a lot, lot longer if you use concrete, and the fence will be more stable if you go to 36 inches instead of 30.

A fence in a dry climate like here in San Diego will last longer than a fence in a wet climate, such as the Gulf Coast where I grew up, so wherever you live could affect the lifetime of the fence as well.

As you're discovering, it can be a little expensive to build a fence, but that is exactly why you should build it right the first time. They are not cheap to build, either in terms of money or time, so spending as much as you can afford to do it as nearly perfect as you can will mean that you won't have to do it again as quickly. Overall the cost per year for one long-lasting expensive fence is less than the cost per year of two shorter-lasting inexpensive fences.

Good-looking and well-maintained fences can also add value to your property, and a less attractive or deteriorating fence can subtract an equal value, so all things considered, it again comes down to going ahead and doing it as nearly perfect as possible within your budget.

If you need to tamp the soil, water is always a good tamper. Set a sprinkler in the area and let it water overnight. Make sure that it is a sprinkler that lets the water soak into the ground rather than one that sprays the same area constantly and possibly causing erosion.

I don't see any reason why you can't use a laser level if you're familiar with how to use them properly.

Hope that helps.