How to install poles under a fence or canopy
The pillar is the support of your future fence and its correct installation is the key to the durability of the site fencing.
This article will discuss all the options for fence posts and how to install them.
I hope this will help you choose the best combination of materials, price and design.
When installing poles, three factors are taken into account:
- fence height and weight,
- depth of soil freezing,
- soil type.
The higher the fence, the deeper the posts are buried. On the fence, if it is solid, the force of the wind will act (and large enough). Deep fixation helps to increase resistance to wind loads. Therefore, at least a third of the height of the fence is “driven” into the ground.
The large weight of the fence will put pressure on the ground and, as a result, resist wind and heaving in the winter. Therefore, the foundation of heavy fences (for example, brick or concrete) is buried smaller, at the level of 40-50 cm.
HOW TO MAKE A SMOOTH FENCE
Installation errors are sometimes irreparable, so it is important to make a clear markup.
Pillars for any fence are made along a stretched string, which is removed only after installation is completed.
The most popular fence post material today is a metal profile.
Its main advantage is the ability to quickly and relatively inexpensively mount supports under the fence with mesh, corrugated board, wooden sections.
The cheapest installation method is to bury a metal pipe in the ground. But for this, the profile must be galvanized.
Another nuance: on moving (heaving) soils, it is better to backfill the pillar not with earth, but with crushed stone.
This will help in summer to accelerate the outflow of moisture (and prolong the life of the fence), and in winter to fight the forces of heaving.
With such a «plastic» backfill, they simply cannot have a significant impact on the support of your fence.
For a canopy and gates, this installation method is unacceptable, so let’s move on to the next option.
It will cost more to concrete the pole. This, one might say, is an “eternal” (relatively, of course) support. For installation with concrete, they dig a hole of the same depth as for backfill — about 80 cm.
It is clear that the consumption of the solution will be noticeable. Is it possible to save? Yes, if you do not dig a hole, but drill it.
Another savings option: concrete only the lower half of the hole, and then fill the pit with the post with earth and carefully tamp.
The options discussed above are spot concreting.
HOW TO CONCRETE A POST
A drainage layer of crushed stone is poured at the bottom of the pit (see the picture above, the option on the far right) fractions of 20-40 mm, layer thickness 10-15 cm, carefully rammed. Do not save and choose crushed granite as more frost-resistant. Of course, the depth of the pit will be sufficient to avoid freezing, but you will add the same crushed stone to concrete.
The solution is poured into the well by two people: one holds the post, the other deals with the solution. The latter is added in small portions to avoid the formation of air gaps that reduce the strength of concrete: poured a little, pierced in several places with a stick, poured again …
Until the composition is “grabbed”, the column is leveled at the vertical level and fixed with oblique stops (ideally on four sides).
An additive that accelerates the hardening of concrete will help shorten the time. Depending on the composition, it can prepare a support in a day, or even faster (carefully read the instructions when buying).
Be sure to use a plug for the top end of the post. It can be welded or purchased plastic.
What to do if necessary TAPE FOUNDATION UNDER THE FENCE?
OPTION 1(for heavy masonry fences)
- dig a trench to half the depth of the post (40 cm),
- pillars are driven into its bottom to a depth of another 40 cm (total relative to the ground level 80 cm),
- formwork is arranged in the trench to a height of at least 10 cm above the ground,
- pour the prepared structure with concrete mortar.
OPTION 2 (for light sectional fences):
- the pillars are buried to the estimated depth (80 cm),
- make a shallow trench at ground level and fill it with sand,
- formwork is arranged along the trench and around the pillars.
To make reinforcement or not — depends on the brand of concrete, crushed stone and foundation parameters.
If you use PC500 cement, without impurities, and granite crushed stone, fraction 20-40, then if the proportions are observed, the concrete will turn out to be very durable.
Under the sectional fence, the load on the foundation is minimal, and therefore additional reinforcement is not required.
If the planned grade of concrete is lower than M250, or the foundation will be loaded in the form of masonry, then the reinforcement will protect the future structure from fractures during ground movements or under its own weight.
Some developers use a combined type of foundation: the underground part is poured with a solution with crushed stone, and the above-ground part is reinforced and poured with a sand-based solution.
I make all the foundations from PC500 (D0), with high-quality crushed stone and reinforce with metal only for high loads. For a fence from corrugated board, reinforcement, in my opinion, is an extra waste of material resources.
This is how (in the photo on the left) the formwork for the fence made of masonry material looks like before pouring.
The result will be a fence with brick pillars, the sections will be heavy (stone or brickwork).
Considering the calculation for the durability of the structure and savings on volume (optimal hole diameter), I recommend choosing concrete of grade M250 and higher. You can read more accurate information on the proportions and nuances of working with concrete in the article of the same name.
Proportions for concreting with reinforcement and without gravel These are for 1 part of cement: 3 parts of sand: 0.53 parts of water. Here you can add reinforcing fiber to increase the strength of concrete.
Wood is a less durable material than concrete and metal, but it gives more scope for the designer’s imagination and the ability to adjust the fence to one or another style of home and garden design.
The enemy of the tree are fungus and insects, as well as the combined effects of moisture and ultraviolet radiation. The most vulnerable part of the post is the first 10 cm above the ground. Hence the conclusion — to protect this particular part as much as possible. Here, the usual impregnation with an antiseptic will not be enough.
There are three exits.
FIRST (on the left in the diagram):process the underground part plus 10-15 cm with bitumen or resin (coated waterproofing for the foundation is sold in hardware stores). Here, as for a metal pole, it is better to use crushed stone backfill and pour a layer of at least 10 cm under the pole.
SECOND (in the diagram on the right): concrete the pillar so that the concrete base rises above ground level by at least 10 cm. The difference from concreting a metal pillar is the need to pour a layer of mortar into the hole over the crushed stone cushion (necessarily mixed with crushed stone), and only after that install the pillar.
Here it is important to choose the right wood for the post (Siberian larch, oak, mulberry, acacia, aspen)
NUANCES of working with a thruster: pay attention to how his ears are located.
I did it in my fence as in the picture, but I ran into such a nuisance as the mobility of the pillar — it swayed across the foundation (fence) line. This was partly due to the fact that the diameter of the screws was less than the diameter of the hole (by 2 mm).
However, if it were possible to remake, I would turn the metal plates 90 degrees. Slight mobility along the fence line is easy to level when mounting the frame.
Another mistake: leaving a leg under the console. The bottom of the console must lie on the concrete, this is important. If you want to raise the post above ground level, then do it with a raised concrete base.
The column on the leg, as in the picture, will sway and, even worse, the console will break off from the iron pin, which, in fact, happened in my case. It was impossible to correct the situation — only complete dismantling.
NUANCE: I dismantled the rest of the concrete plinths more successfully and reused it: I moved the fence line and pulled the grid over the poles. And you can also lay logs on them and lay a terrace cover …
In general, this installation of wooden poles I I think is the best.
WHAT IS THE BENEFIT OF A PILLAR ON A CONCRETE PLATE. The length of the pole is shortened to the height of the fence (saving on wood), the pole treated with protective impregnation and covered with yacht enamel (alkyd varnish) will serve for a long time, and after that it can be replaced, while updating the design of the fence.
Considering that wood is a more affordable material (but this already depends on the area), the fence will turn out to be quite budgetary.
Indeed, on a wooden pole without welding, you can hang a cheap plastic mesh, chain-link, wooden sections and even corrugated board.
Gate posts must endure baboutheavy loads (if the gates are hinged), so the concrete base under them is made with a diameter of 20-25 cm over the entire height (they simply fill the hole), the pillar itself is still made of iron and concreted.
How to install poles under a light gate is shown in the diagram at the top right.
NUANCE which should be remembered: the presence of a reinforced concrete dressing between the supporting pillars of the gate or gate is mandatory. Without it, the top of the pillars will “walk” and the doors will either not close or will form a gap.
If such a pole is simply buried in the ground, you will get a very cheap option for supports under the grid. Ideal for quick and temporary fencing or large perimeter areas.
There are two drawbacks: low strength (it can crack from a strong blow) and the inconvenience of mounting on a round pole (either clamps or wire tying).
The strength of the pipe is increased by pouring concrete mortar inside, which will raise the cost of installation.
This is a very durable and reliable option for fence and gate supports. A quality mortar can guarantee you a service life of 30 years or more.
As for the installation method, it is enough to simply bury the post under sections made of wood or lighter corrugated board. The immersion depth for any standard fence height is 80 cm.
Under the gate and the gate, such pillars must be concreted to avoid distortion during seasonal ground movements.
The basis of a brick pillar is a concreted metal profile (reinforcement).
With such dimensions and solid weight, it is not always reasonable to dig a hole 80 cm deep, you will get nothing but cost overruns. A depth of 40-50 cm is enough, and then a metal rod is driven into the ground to the depth of soil freezing.
When pouring, wooden formwork is used to raise the level of the foundation and protect the brick from excessive moisture.
Waterproofing (roofing material) is laid between the foundation and the brick.
As the column grows, the reinforcement or pipe in the hole is poured with concrete.
Under the fastening of the gate hinges or the log for the fence sections, metal dressings are welded to the pipe. This is done during the masonry process so that the connecting elements lie between the bricks.
What else to read on the site:
Corrugated fence: important points
Decking very quickly «won the hearts» of homeowners, not only because of the bright colors of metal profile manufacturers. In terms of price category, such a fence is between the budget option from the grid and the masterfully executed wooden one. And considering baboutmore …
DIY wooden fence
Fences made of wood are considered the most short-lived. After all, not everyone knows (or does not want to know) the secrets of wood and its processing. Neoa processed pine fence will indeed last no more than 10 years, and even then, provided that the lower part of the pillar is waterproofed. If you do…
Design of the courtyard of a private house
The yard, whether it is large or small, is the first thing we see when opening the gate, which means that it is the visiting card of the house. Any owner of the estate, to one degree or another, but still wants to impress the guests, because the theme of the design of the local area will be relevant…