If you’re walking to build your very own deck one of the very first considerations after ~ you’ve laid out your articles is exactly how deep her footings need to be set.

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This is determined by the frost line in your area and also the map listed below should offer you a general idea of exactly how deep you must go.

What is a Frost Line

The frost heat is the depth in ~ which the soil freezes. It’s vital to know the frost heat depth for construction purposes. Water pipes should constantly be set below a frost line to protect against them from freezing in the winter.


It’s also important the the footings for a building or a deck well below the frost line so the short articles don’t transition as the soil freezes and thaws. Check your local building codes to recognize the proper depth previous a frost line a footing need to sit.

When come Build

If you room in a cold zone and also aren’t in a rush to build, it’s finest to wait until spring to start digging. The ground will be s by climate making it easier to dig to the ideal depth.


Mark a stick at the proper depth and keep it within straightforward reach the your building project therefore you have the right to take consistent measurements.

Frost heat Map

This frost line map gives a basic idea of whereby the frost line is in her area. If you live on the sheet of the line, it’s ideal to go with the recommendations of the colder side to avoid any type of issues.


This map is indigenous the nationwide Snow and Ice Data center and shows the frost heat map across the united States. Note exactly how it moves under from 72-inch depth to a 6-inch depth.

The best frost line depth is 100-inches as seen near the tip of Minnesota, north Dakota, and also Alaska, every the method to zero inch in Florida, southerly Arizona, and southern California.


Frost heat by Zip Code

If the map isn’t accurate sufficient for you. Inspect your frost heat by zip code or deal with using this map from the nationwide Weather Service.

As we stated before, make sure you examine with your local building codes prior to you start digging.


Tips for Digging

Anytime you room digging, it’s ideal to recognize the frost line together you will know just how deep the water pipes room so you can avoid them.

Here in Los Angeles where the floor doesn’t freeze, the irrigation and sprinkler pipes room not buried an extremely deep, so you should be extra cautious when digging roughly them.


A shovel and post feet digger room all the is necessary to dig a deep hole, but if you’ve got big rocks or difficult pack in your area then a long pry bar is also helpful.

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An auger is the fastest means to destruction holes and can save you a the majority of time and money also with the expense of renting. A handheld auger is generally the ideal option together they space cheaper come rent and also easier to work with and maneuver. Because that a lengthy fence heat an auger in ~ the finish of a bobcat or PTO tractor is a good investment as it will certainly dig the feet fast and accurately.