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1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsDeck posts and fence posts may look similar, but they do different jobs: a deck post carries structural loads, while a fence post supports a fence run, gate, or wire. Use the locally applicable deck design and footing requirements for structural posts; use fence-specific guidance for ordinary fence posts. A fence-post depth rule is not a deck-footing design.
Start by identifying the post’s job
Before digging, establish whether the post supports a deck or a fence. Deck footings and connections must be designed for the structure’s loads. Fence-post depth and setting method depend on the fence, soil, frost conditions, wind exposure, and local requirements.
- For a deck: check the locally adopted residential code, approved plans, and any required permit or inspection. If code applicability, soil conditions, loads, or the design are uncertain, get project-specific professional guidance.
- For a fence: check local requirements and account for fence type, panel width, gates, slope, soil, and wind exposure before choosing spacing and hole details.
Before excavation for either project, arrange an underground-utility locate and confirm permit requirements with the local building department.
How deck posts should be supported
Size and depth are design questions
The 2018 International Residential Code (IRC), Section R507.3, states: “Decks shall be supported on concrete footings or other approved structural systems designed to accommodate all loads in accordance with Section R301.” Under that edition, footing size must support imposed loads, and footing depth follows the code’s frost-line provisions, subject to specified exceptions. Local adoption and amendments determine which requirements apply. The IRC includes a limited frost-depth exception for qualifying free-standing decks; its conditions should be checked in the adopted code rather than generalized.
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#1 Best Overall
- SAVE YOUR BACK: Quick, lightweight patent pending technology replaces 80-100lbs of concrete with a lightweight bag that does not require messy mixing with water that requires cleanup & preparation for filling post holes
- FAST & SECURE: Ready to build in 15 minutes, and mixes in seconds in place and in the bag. All that you need in a compact and lightweight 2.5lb bag that mixes into a waterproof protection for your deck post, fence post, mailbox, and playground equipment
- PRO TECHNOLOGY: It's the same technology used to set utility poles by the professionals. Now you can quickly and securely set your fence posts and mail posts with a minimum of fuss & mess securely.
- EXPANDING COMPOSITE TECHNOLOGY: Fast 2K Deck uses an expanding composite technology which is stronger than traditional concrete. Designed to adhere to wood, Vinyl and metal posts.
- HYDROPHOBIC TO PREVENT ROT: Unlike concrete which absorbs water which can damage metal and wood, the Fast 2K Deck product is waterproof and hydrophobic which prevents water from getting into your posts, reducing rot, rust, deterioration and other water-related damage.
Do not use a fence-post burial rule or a fence-mix manufacturer’s hole dimensions to size a deck footing. The American Wood Council’s DCA6 guide is a prescriptive guide based on the 2015 IRC, with its own limits for details such as post placement, post-to-beam connections, and bracing. Its details are not automatically valid for every deck height, load, code edition, or jurisdiction.
Restrain the post at the footing
The 2018 IRC, Section R507.4.1, requires lateral restraint where a deck post bears on a concrete footing. The code describes manufactured connectors or at least 12 inches (305 mm) of post embedment in surrounding soil or concrete piers as options. It also says surrounding soil must not be relied on for lateral support where it is expansive, compressible, shifting, or otherwise questionable. Confirm the locally adopted code and use the selected connector’s specified fasteners and installation instructions.
Rank #2
- SAVE YOUR BACK: Each bag of Quick, lightweight Fast 2K Deck Mix replaces 80-100lbs of concrete with a lightweight bag that does not require messy mixing with water that requires cleanup & preparation for filling post holes
- FAST & SECURE: Ready to build in 15 minutes, and mixes in seconds in place and in the bag. All that you need in 10 compact and lightweight 2.5lb bags that mix into a waterproof protection for your deck post, fence post, mailbox, and playground equipment
- PRO TECHNOLOGY: It's the same technology used to set utility poles by the professionals. Now you can quickly and securely set your fence posts and mail posts with a minimum of fuss & mess securely.
- EXPANDING COMPOSITE TECHNOLOGY: Fast 2K Deck uses an expanding composite technology which is stronger than traditional concrete. Designed to adhere to wood, Vinyl and metal posts.
- HYDROPHOBIC TO PREVENT ROT: Unlike concrete which absorbs water which can damage metal and wood, the Fast 2K Deck product is waterproof and hydrophobic which prevents water from getting into your posts, reducing rot, rust, deterioration and other water-related damage.
A post base is not a universal substitute for a designed connection. Choose the base, fasteners, and post-to-beam detail to match the plans and code. Simpson Strong-Tie provides installation guidance for its PB and PBST bases; follow the instructions for the specific product rather than assuming different bases install or perform identically.
How to lay out and set fence posts
Plan the line before digging
Establish end and corner locations first, then mark the line posts using a taut string or another layout line. Check corners and keep posts aligned to the planned line. Fence design, panel width, gates, slope, wind, soil, and local requirements can all affect spacing and hole details.
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Rank #3
- LARGE PACK 33.8oz - Will Intall x2 Posts | Replaces 80-100 lbs Concrete
- QUICK & STRONG CONCRETE ALTERNATIVE - Postsaver Pro-Set Post Fixing Foam is a rigid post setting foam that's 97% lighter than concrete & 100% laterally as strong. It's a convenient substitute to traditional concrete post mix, making installation a lot easier with no water required.
- EASY TO USE - Simply shake this fence post foam in the bag for 60 seconds & pour around the post in the hole. No water needed! In 3-5 minutes, it'll start to expand & harden until it reaches its full load strength in 90 minutes. Easily cut excess away or backfill during expansion to prevent foam egress.
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- LIGHTER & MORE ECO-FRIENDLY - One pack of Pro-Set expanding foam post mix installs 2 posts (when using a fencing spade). Save energy, time & cost (eg transportation/delivery cost for heavy concrete) with Postsaver Pro-Set! Plus, it's more eco-friendly due to far less CO2 being produced during manufacture than concrete.
Choose depth for the site and fence
There is no single burial depth that suits every fence. Treated Wood gives at least one-third of the post’s length as a general guide, while noting that code, freeze-thaw conditions, soil consistency, and wind may require deeper burial. Its guide also recommends going below the local frost line. Treat these as general guidance, not a substitute for local requirements or site-specific judgment.
QUIKRETE’s fence-post method describes a hole about three times the post’s width and a depth of one-third to one-half of the above-ground post length, plus 6 inches for gravel. Those are manufacturer instructions for that method, not universal fence dimensions and not a structural deck-footing specification.
Rank #4
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- FAST & SECURE: Can be used in ambient temperatures ranging from -5°F to 105°F. Mixes in 30 seconds, sets in 5 minutes, build on post in 30 minutes. Product does not require water or any additives.
- EXPANDING COMPOSITE TECHNOLOGY: Works with multiple post materials and projects: wood, metal and vinyl, decks, fences, mailboxes, pole barns, and more.
- HYDROPHOBIC TO PREVENT ROT: Adheres to post assisting in prevention of rot or corrosion.
- PRO TECHNOLOGY: Meets building code requirements for special foundations and load-bearing elements.
Use posts rated for burial
For buried wood posts, use lumber treated for ground-contact or below-ground exposure. The USDA Forest Products Laboratory advises: “For maximum protection against wood decay and termites, use posts that have an in-depth preservative treatment, preferably a pressure treatment for below ground use.” This is preservation guidance, not a guarantee of service life. Follow the treatment system’s instructions for cut ends where applicable.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Set a fence post plumb and keep it there
- Dig the planned hole. Use the depth and diameter appropriate to the fence, site, and selected installation method. A post-hole digger or power auger may be suitable, depending on the job and access.
- Add gravel only if the method calls for it. Some guidance describes compacted gravel at the bottom to help manage moisture; follow the chosen method rather than treating gravel as mandatory for every installation.
- Position and brace the post. Secure it with braces and stakes before placing setting material.
- Check plumb on two adjacent faces. Use a level on two sides meeting at a right angle, and adjust the braces until the post is vertical in both directions.
- Place and finish the setting material. Follow the mix package directions. Where the method uses concrete, shape the top to shed water away from the post.
- Keep the brace in place as directed. Do not load or disturb the post until the product instructions and conditions allow it.
QUIKRETE says its fast-setting mix typically sets in 20–40 minutes and describes waiting four hours before applying heavy weight in normal conditions; cooler temperatures require additional time. These are product-specific statements, not a general concrete cure schedule. Follow the directions for the mix you use and the actual site conditions.
Best Value
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Concrete, connectors, and materials: what changes by project
| Decision | Deck post | Fence post |
|---|---|---|
| Primary concern | Structural footing and connections sized for loads under the applicable code and design. | Stability for the fence, gate, or wire under site conditions and local requirements. |
| Depth | Determined by the applicable code, footing design, frost provisions, loads, and any valid exception. | Depends on the fence and site; general guides vary, and code, frost, soil, and wind can call for more depth. |
| Concrete or other support | Use concrete footings or another approved structural system designed for the loads. A fence-setting recipe is not a deck design. | Use the fence method selected for the application and follow its directions; QUIKRETE also describes a method for setting posts without mixing. |
| Post connection | Use the designed post-to-footing and post-to-beam details, including compatible connectors and fasteners where specified. | Use a setting method and post appropriate to the fence; do not assume a deck post base is required for an ordinary fence post. |
| Wood in ground | Where wood is buried, use wood treated for below-ground exposure. | Use wood treated for ground-contact or below-ground exposure. |
The table distinguishes the jobs; it does not replace project plans or product instructions. QUIKRETE’s setting-post dimensions apply to its fence-post method, and its structural or load-bearing applications, such as deck posts, require its separate footing and form directions. Likewise, deck connectors must match the design and the manufacturer’s installation instructions.
Tools, safety, and when to get help
Depending on the project and selected method, useful equipment may include a post-hole digger or power auger, a level, braces and stakes, gravel, suitable posts, and concrete mix. For a deck, include the footing and compatible post-base or connector system specified by the design.
Quick Recap
- Arrange a utility locate before digging and verify local permit and inspection requirements.
- Wear eye protection, gloves, and a mask when directed by the cement-based product manufacturer.
- Get project-specific help for unusual or questionable soil, retaining conditions, tall decks, significant loads, or unclear code requirements.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
