How big of a footing do I need for a 4x4 post?
3. FOOTINGS: - Poured concrete footings should be a minimum of 8” wider than the posts (4x4 post – 12” min. width, 6x6 post – 14” min.
Depending on the type of soil, the footing diameter at the base must be a minimum of 15", 12" or 11" for the corner post and 20", 17" or 15" for all intermediate posts.
Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. Footings also must extend at least 12 inches below the frost line (the depth to which the ground freezes in winter) or must be frost-protected.
The minimum reinforced concrete footing thickness will be 6 inches or 1-1/2 times the length of the footing projection from the foundation wall, whichever is greater.
Dig post hole so diameter of the hole is 3 times the width of the post (i.e., the hole for a 4” wood post should be about 12 inches wide). The depth of the hole should be 1/3-1/2 the post height above ground (i.e., a 6-foot tall fence would require a hole depth of at least 2 feet).
Mix two 50lb bags of concrete with water in a mixing tub or 5-gallon bucket. Add concrete into the hole and around the 4” x 4”. Depending on your climate, let concrete set up for 24 - 48 hours.
Detailed Solution. As per Cl. 7.2, IS:1904, All foundations shall extend to a depth of at least 50 cm below the natural ground level.
Footings & Foundations.
The top of the footing shall be a minimum of 42 inches below finished grade and have footing diameters complying with the following tables based on soil conditions at the site and calculated weight bearing on the posts.
Plain concrete deck foundations without rebar are acceptable under the minimum standards of construction established in the International Residential Code. However, placing reinforcing steel within footings is a relatively easy and inexpensive practice that can provide increased performance.
When deck footings aren't poured deep enough, decks can heave. Sandy, well drained soils aren't particular susceptible to frost heave, while soils with higher clay content are prone to frost heave. This is why it's so important for deck footings to extend down below the frost line.
Do you put gravel under footings?
While discussing our project with local excavators, several mentioned that they commonly include 4 to 6 inches of crusher run gravel UNDER the footings – properly compacted, of course – to improve forming and pouring of the footings.
- Settlement. Settlement is defined as the vertical movement of the ground which is caused by stress alterations. ...
- Vibration. ...
- Lateral displacement. ...
- Ground heave. ...
- Tilt. ...
- Durability.
Footing thickness - 8 to 12 inches. Footing depth - varies based on frost line and soil strength (some footings can be shallow, while other must be deep)
Step -1: Determining size of footing:
For simplicity, self weight of footing and weight of soil on footing is considered as 10 to 15% of the vertical load. Therefore, total load P = 1100 kN. Size of footing to be designed can be square, rectangular or circular in plan.
If properly treated and installed, pine fence posts can last for 20–35 years; untreated pine posts might only last 3–7 years.
The general rule of thumb when setting a post is that the depth of the post's hole needs to be one-third to one-half of the actual above-ground height of the post.
Stabilize Your Fence Post
You'll first want to dig a few inches of soil out from around the post's perimeter. From there, you can fill the hole with gravel and top the gravel with a rapid-set cement mix. Finally, pound the fence post back into place using a mallet.
The recommended thickness for a car lift concrete slab is 4 inches minimum for most two-post lifts and four-post lifts.
How Deep Should a Fence Post Be? For an average fence post, about 6 to 8 feet tall, prepare to dig a post hole about 2 feet deep. To install a fence post, you'll need a shovel or post digger, a 6-foot level, soil, and gravel or crushed stone. For gateposts, you'll need concrete too.
The depth of concrete you need will depend on the use: footings for extensions, for example, will need to be at least 200mm thick, while around 100mm should be deep enough for a shed base.
At what slope should a footing be stepped?
Footings shall be stepped where it is necessary to change the elevation of the top surface of the footing or where the surface of the ground slopes more than 1 unit vertical in 10 units horizontal (10-percent slope).
Any deviance in the footing from straight, level, or plumb will cause significant problems later. Here's why: ICF walls, when filled with concrete, will move so they are perpendicular to the surface—the footing or slab—they are set on. If the footing isn't absolutely dead level, the wall will be out of plumb.
You should not have your concrete slab poured before building your pole barn. After the poles are set and skirt board is placed around the perimeter of the poles, you will have a form to pour your concrete foundation. Concrete is normally poured through the large door opening.
Poured-in-Place Foundation
This pole barn foundation is popular with residential buildings. The wooden forms, or molds, shape the walls of your pole barn foundation. They're also built around steel rebar, which adds additional strength. Then, concrete is poured into the wooden forms.
To calculate the load, you should use 40lbs per square foot for live loads (these are variable loads that are dynamic such as the weight of people and furniture) and 15 lbs per square foot for dead loads (this is the weight of the materials used for the construction of the deck) for a total load weight of 55 lbs per ...
You are right in your assumption that you should not pour around the post. Concrete experiences fractures quite often, especially microfractures around points of varying stress (i.e. at the edge of a post). Additionally, any moisture/water that may enter your basement will probably get into the post.
A shallow foundation (as defined by B1/VM4) is one in which the depth from the ground surface to the underside of the foundation is less than five times the width of the foundation. All other foundations are considered deep foundations.
Digging can be done by hand. i am doing mine at the moment - same size also in clay. takes about an hour a meter . It is really hard work but can be done and doesn't take as long as people think.
If your neighbour is planning to construct a basement or excavate close to the side of your property, then your neighbour is entitled to underpin or otherwise safeguard the foundations of your building, and then has a right to put new foundations (underpinning) on your land.
Because concrete is a very porous material, it will absorb any moisture that it contacts. This can cause pooling. Without crushed stone, pooling water will settle under it and erode your slab. Adding a layer of crushed stone will add proper drainage, as well as create a barrier between your slab and the ground.
What size of gravel is for footing?
Gravel used for the foundation should be sized between 25-40mm. It is important to note when selecting coarse aggregates or gravel, ensure that the mix is similar in size and shape to avoid honeycombing and seepage.
- Individual Footings. Individual footings are the most common type of footing. ...
- Combined Footings. Combined footings are used when two or more foundation walls are close together and they share the load. ...
- Strip Footings. ...
- Raft or Mat Foundation.
You do need gravel under a concrete slab, footing, or patio. Gravel provides a solid foundation for your concrete as it can be compacted. It also improves drainage, preventing water from pooling beneath the concrete.
Post lengths for fences start at 8 or 10 feet for a 6-foot-tall fence. They are commonly four-by-fours, which measure approximately 3 1/2 by 3 1/2 inches, or six-by-sixes, at around 5 1/2 by 5 1/2 inches.
The one caveat is that the AF&PA has reduced its recommendations for the maximum post height. While the tables allow posts to reach a height of 17 feet in some instances, the AF&PA now recommends going no higher than 14 feet.
Required thickness for footings.
Concrete footings typically have a required thickness of 6” to 10”.
Start with a gravel base
*To help prolong the life of your fence, many sources contend it is a good practice to dig a little deeper to place at least 6″ of clean, clear 3/4″ gravel at the bottom of the holes prior to the placement of posts.
Placing a thick layer of loose gravel at the bottom of the post hole will allow groundwater to trickle through the rocks and down away from the base of the post. This will prevent the post from rotting by keeping it constantly dry. You can purchase gravel at a local hardware store or landscaping-supply business.
The standard spacing for fence posts is 8 to 25 feet apart, depending on the type of fence. A standard wood fence would require posts 8 feet apart, while a high-tensile wire could span 25 feet.
It doesn't matter if it is a do-it-yourself (DIY) project or a professional installation, wood fence or vinyl fence, your fence posts should be set in concrete. Without a properly set concrete footer, your fence posts will begin to sag until they eventually fail.
Is a 6 inch hole good for a 4x4 post?
Post Holes-
For example: A 4x4 post (actual size 3.5"x3. 5") has a maximum width of just over 5" (diagonally). Therefore, the 4x4 post will likely fit into a hole drilled by a 6" diameter auger.
The maximum spacing of 4x4 deck posts should be 6 feet on center, while the maximum spacing of 6x6 deck posts should be 8 feet on center.