Table of Contents
Should deck posts be set in concrete?
A deck post should always be placed on top of footing, not inside concrete because it can break. Concrete tends to absorb moisture and wood expands when it gets wet, so these two factors combined will result in the wood breaking the concrete.
How deep do post holes need to be for a deck?
Dig the holes six inches deeper than the required frost line depth for your area, and slightly wider than the concrete footer tubes you’ll be using. A power auger can make this step easier and faster.
Should deck posts be 4×4 or 6×6?
Deck posts must be a minimum of 4×4 according to the IRC but many jurisdictions require a 6×6 post as a standard. To avoid code violations, many deck builders choose the 6×6 even if the 4×4 is acceptable.
Will decking posts rot in concrete?
The post will only rot at ground level, it does not matter what you put in the bottom of the hole. A pressure treated post will last around 10 years. if you use metposts the post will still rot they just make it easier to replace & in my opinion they look horrible.
How far apart should posts be for a deck?
Layout and Footing Locations Starting with your perimeter, mark the location of each deck post to locate the fitting position. In general, posts should be spaced no more than 8 feet apart. Some builders position them every 4 feet for a completely rigid frame.
Do deck posts need to be below frost line?
There are several ways to set deck posts; we recommend attaching the posts to concrete footers above the ground. This helps to prevent wooden posts from rotting. Set footers a minimum of 6” below the frost line for your area to prevent movement during freezing temperatures.
How do you calculate deck posts?
To calculate it for a particular post, imagine a plan view of the deck (see illustration, left). Draw a line through the mid-span of the joists. Then find the mid-span of the beam that the post supports, and extend lines from there back to the line at the joist mid-span. Find the area within the lines.
How many bags of concrete do I need for a deck post?
In order to have enough concrete for one cubic foot, you’ll require 2.2 bags of 60-lb concrete. Since bags are only sold in whole (not half, or quarter) quantities, you’ll need to purchase three (3) 60-lb. bags for one cubic foot.
Can I use deck pier blocks instead of footings?
Pier blocks can be used instead of footings for a ground-level deck not requiring permits. Any decks higher than 24” require concrete piles 10” in diameter and 48” below grade. These footing size requirements are to ensure enough soil bearing to prevent the joist from sinking in the ground.
How do you attach a 4×4 post to a 4×4?
The simplest way to connect two 4x4s is with a butt joint. Trim the ends to be joined so they are square and smooth. Any angle, however small, can act as a shear line, and a smooth flat surface makes for a better connection.
Can you use 4×4 posts for a deck?
In the past, many decks were built with 4×4 support posts (also called structural posts). But these can bow seriously, even if a deck is only 3 feet off the ground. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them.
Should you notch deck posts?
Say “No” to notching pressure-treated deck posts. We want you to build an outdoor railing system that you, your family and guests can enjoy without worrying about safety issues. In order to do so, you need to know this building shortcut is not advisable, and we recommend avoiding it at all costs.
How much load can a 4×4 post support?
An 8-foot 4×4 can typically carry 1,000lbs horizontally along its length without excessive sag, or 500lbs in a center load. Supported at 16” centers and the load jumps to 4,000lbs. When used as a post, the same 4×4 can support up to 6,000 PSI and even more if properly braced.
How much weight can a pressure treated 4×4 hold vertically?
Generally, you can expect a vertical 4×4 to support at least 4,300 pounds, but the amount of weight could be significantly higher than that in some cases. Even at 12 ft high, a vertical 4×4 made out of No. 2 Southern Pine will hold over 3,000 pounds.
How long will a treated 4×4 post last in the ground?
How Long Will A Treated 4×4 Last In The Ground? (Explained) A treated 4×4 will last 20 to 25 years in the ground if the conditions in the soil and climate are favorable. That number could increase to 40 to 75 years if you install the treated 4×4 in a cement ring rather than the soil.
What should I put between wood and concrete?
Anyplace where wood meets the ground or concrete, the lumber must be pressure treated. For additional moisture protection, a gasket or strip of closed-cell foam can be installed between the concrete foundation and the sill plate.
How long will a pressure treated 6×6 last in the ground?
Pressure treated lumber can extend the lifespan of outdoor projects. It protects against rot and insect damage but requires regular maintenance and treatment to prevent moisture damage. With care, treated wood will last 40 or more years.
