Useful Tips

How to protect wood poles in the ground from rotting

Wood remains the most common building material that owners of country houses and cottages use for the construction of various fences on the site. The wattle fence between the recreation area and the beds near the cottage will look harmonious, a beautiful wooden fence around the country house or a low wooden fence around the flower beds in the yard. But unprotected wood is subject to rapid deterioration due to constant interaction with rain, wind, snow, sun.

On shaded areas in the yards of cottages, in places with high humidity, boards quickly lose their original appearance and become moldy or affected by fungus. How to process the fence posts and the boardwalk of the country house itself so that they retain their attractive appearance for more than one year? There are many available methods of processing wood, although, for example, poles for the fence require the use of different protective equipment for the outer part and the one that is buried in the ground.

Common mistakes when installing wooden poles

Initially, it is important to understand the reasons why the support pillars for the fence become unusable and how to handle them. This happens, first of all, under the influence of moisture, which, impregnating the wood, creates "good" conditions for the development of all kinds of bacteria. And if the top of the column under the sun and the wind manages to dry out, then in the place of contact with wet ground the process becomes irreversible. The tree begins to rot, becomes moldy, there are insect pests. The processes of decay in the lower part of the column are somewhat slower, but inevitable. There is no better way to prevent this process than treating the fence posts with antiseptics and waterproofing their lower part.

Typical mistakes of summer residents when installing wooden poles include the incorrect selection and installation of logs, as well as non-compliance with the rules for processing the underground part.

When choosing the pillars, you should pay attention to the general condition of the wood - the absence of signs of rot, blueness, pests. The moisture content of wood should not exceed 15%. The logs before treatment with antiseptics need to be sanded and dried.

It is important to determine where the log is top and bottom, since the pole must always be dug up by the top. This prevents the “suction” of water through the capillaries.
In no case do not wrap the treated end of the tree with roofing material, since when moisture gets into such a “glass”, it will always remain there, creating conditions for decay.

The processing of wooden poles is necessary with drugs that have antiseptic, moisture and fire retardant properties.

The compositions for processing the underground part of the pillars

There are many folk methods of how and how to process the posts for the fence.

Here are a few of them:

  • Coating with birch tar or spruce resin (the oldest and most proven method).
  • Waste car oil treatment (the cheapest way). The oil is applied in several layers in a heated state, carefully soaking all the ends and cracks. 90% of the mining composition is mineral oil - a good water-repellent antiseptic. The acid salts contained in the waste kill any fungus in the wood.
  • Firing and bitumen treatment. That part of the log that will be buried in the ground can be burned either at the stake or with a gas burner, creating a charred layer of several millimeters. The calcined portion is treated with molten tar or bitumen.

The protective layer is applied in two steps, so that each layer of bitumen impregnation can harden, you need to withstand the drying period of the first layer for about a day. Bitumen impregnation is accordingly black, so it only process that part of the wooden fence post that will be hidden in the ground.

It is not recommended to apply bituminous impregnation on wooden poles during fog or rain.

In the construction market, they also offer all kinds of synthetic waterproofing compounds - mastics, pastes, etc. For example, the bitumen mixtures Biom-2 or Izhora, several layers of which, combined with a fiberglass mesh and a protective film, create excellent waterproofing with high protective properties, designed for 10-15 years of operation. Moreover, a 15-pound bucket of such a mixture costs only 450 rubles.

Neomid 430 eco - preserving non-washable antiseptic for external use, which provides maximum protection for wood with prolonged contact with soil and moisture. It protects against damage by wood-destroying and wood-staining molds, algae, mosses, as well as woodworm insects for up to 35 years.

Installing unprocessed posts is strongly discouraged.

Step-by-step instructions for installing and protecting pillars

We determine where the comel is on the log and mark that it will be the top of the column. Before proceeding with the installation of posts for the fence, it is necessary to treat its lower part with a penetrating antiseptic to a height of 1.5 meters. It is better by immersing for two days in a 5% solution of copper or iron sulfate. You can also apply a 5% solution of potassium dichromate in 5% sulfuric acid, the remaining solution will need to soak the soil around the dug column. This will provide antifungal protection for 15-20 years.

After impregnation with an antiseptic, the buried part is treated with one of the types of waterproofing (bitumen, tar, mastic, mining, etc.).

We make the process of installing the pillar. There are several different ways, some of which provide additional protection for the column from interacting with wet soil.

Option one (the cheapest). The treated end of the column is buried in the ground and carefully tamped. After a few years, it is necessary to check its base for the appearance of fungus or rot.

Option two. Prepare a hole with a depth of a little more than a meter and twice as wide as the diameter of the column. The bottom is covered with gravel, then a glass is placed around the perimeter without a bottom made of geotextiles or other non-woven material, which will protect the backfill from gravel from clogging with the ground. The whole space is not covered with soil, but with gravel or rubble, carefully tamped and spilled with mining.

The third option (the most expensive, since the purchase of pipes is added to the costs). The use of sleeves from a metal or asbestos-cement pipe, into which a wooden pillar is inserted. Since the sleeve rises 10 centimeters above the ground, the tree will not have direct contact with the ground, and therefore undergo decay processes.

The process of installing a wooden pole in a sleeve requires thoroughness and time. To prevent the pillar from falling in, you should pick up a piece of pipe (100 cm) with a diameter less than a centimeter diameter of about 10 centimeters. A log is laid on the goats and a circular cut is made at a height of about 30-40, and then with the help of an ax they remove the necessary layer. The resulting cylinder should enter the pipe freely.

First, this part of the column is impregnated with drying oil or working out, and allowed to dry for several days. Then the tar is heated at the stake to a liquid state, the chipped end of the column with a brush is thickly coated with hot mass and a piece of pipe is planted. The gap between the tree and the pipe and the lower part of the column is also treated with tar. Bury the resulting pillar so that the top of the pipe protrudes slightly above the surface of the earth.

Impregnation of the visible part of the column with an antiseptic and the application of the main coating (paint, varnish). To further protect the pole, experts recommend closing it with a tin cover.

Protective coatings for the visible part of the column

The upper part of the column, which is located above ground level, also requires special protection with both antiseptics and protective paints and varnishes. To understand how to process the fence posts, determine the type of coating. If it is important to preserve the wood texture, then on the market such coatings as Pinotex or Belinka, Biotex, AVIS Timbercoat varnish have long established themselves.

If you plan to apply paint, then both simple domestic oil paint based on zinc white and wood paints of the largest foreign manufacturers Tikkurila (Finland), Selena (Poland), Alpa (France), Akzo NV are suitable "(Netherlands)," Belinka Belles "(Slovenia).

Before applying a coat of paint, the tree is always primed.

The paintwork should be renewed every three to five years to protect the tree from rotting and damage by insects.

Advantages of installing wooden poles

Wooden poles for the fence are suitable as a supporting structure for wooden and metal fences, corrugated boards. Along with reinforced concrete and metal supports, wooden ones are still often chosen. Why:

  • Low cost is one of the key reasons. Even processed logs will cost much less than products from other materials,
  • Product availability is also an important advantage. Pillars can be bought ready-made or made by yourself,
  • The ease of installation of pillars eliminates the need for lifting equipment, the process is available to any inexperienced developer,
  • The environmental friendliness and aesthetics of natural wood do not need to be introduced. You can give the log any shape and sculpt any carved ornament on it.

What to look for

Others will call it shortcomings, but we will reformulate them in particular, which must be taken into account when choosing wooden posts to obtain an effective and lasting result:

  • Wood is sensitive to moisture, both from soil and from rains, fogs, thawed snow. In order for the product to retain its shape and characteristics, it is necessary to treat it with waterproofing compounds.
  • Protection of wooden poles from rotting in the ground is ensured by the application of antiseptic impregnations on the lower part of the product and its additional waterproofing.
  • The service life compared to concrete and metal in wood is short, but it can be extended with proper care and timely processing of the product.
  • Wooden supports are able to withstand only lightweight fencing structures, they are not suitable for forged and concrete structures.

How to make a post yourself

Buying ready-made supports will cost much more than products of own production. To independently make poles for the fence, you will need trunks of deciduous trees:

It is not recommended to take coniferous tree trunks: they are soft, dry quickly and give significant shrinkage.

The minimum diameter of the support should be 15 mm, as much as possible.

To make a pillar, you need to take a pillar of stable thickness and remove the bark from it. If desired, the surface can be leveled with a planer and carved, to give the log a shape.

After manufacturing, the product must be coated with antiseptics, which will prevent the column from getting wet and protect it from decay. A coating in 2 layers will not be superfluous, special attention is paid to the ends of the support, which absorb the most significant load and are least protected from water penetration.

How to process wooden poles before digging into the ground

Antiseptic coating alone is not enough to protect the underground part of the pillar. It must be treated with waterproofing compounds. To do this, fit:

  • Liquid molten bitumen,
  • Special polymer coating paste,
  • Tar,
  • Technical development.

For waterproofing the underground part of the column, it is precisely liquid coating that is needed. It adheres tightly to the material and creates reliable protection. Roll wraps are ineffective in this case.

Mounting a fence with wooden poles

The principle of the installation of wood poles for fences is as follows:

  • The installation site is cleaned of the fruit layer, rhizomes of plants are removed for ease of work,
  • They dig a hole with a garden drill of a suitable diameter or call up special equipment,
  • A pillow of crushed stone and sand is falling asleep at the bottom,
  • Lower the support into the pit
  • Backfill the soil and compact it thoroughly.

Based on this principle, several methods for convenient mounting of supports and a fence are based.

Method 1. Work with finished products

The first method involves the use of ready-made pillars as a support. It is necessary to purchase a set of wooden trimmed logs, treat the underground part with an antiseptic and waterproofing and immerse the pillar in the ground in a pit prepared according to the main method.

Fast installation and the absence of labor for the manufacture of supports save time, but not money.

Method 2. Installing the supports in the standard way

This installation method is good in that it repeats the basic plan algorithm, but has several distinctive features:

  • The use of geotextiles to filter water and stabilize the soil layer. By the way, this is one of the ways to dig a wooden pillar into the ground so that it does not rot,
  • Backfilling of the pit can be done not with soil, but with rubble or large gravel. Such a backup is more reliable than soil, and also drains the soil from groundwater. When soil is heaving, the column will not be forced out of the pit due to the work of large particles.

Method 3. Eliminate Rotting

Another way to protect wooden poles in the ground from rotting is to cast concrete. They replace the backfill of the soil. How to implement the process:

  1. The pit is prepared in the usual way: drilling, sand and gravel cushion device.
  2. The walls of the pit need to be laid with 1-2 layers of roofing material. It will protect concrete from water, perform the function of formwork for mortar.
  3. The treated log is inserted into the pit, fixed with a wire strapping strictly in an upright position.
  4. Pour concrete mortar and compact it with a submersible vibrator.

This method of installing wooden poles has several advantages:

  • The lack of contact between wood and soil eliminates the decay of the latter,
  • Supports significantly increase their service life compared to conventional burrows. On poles you can install heavier fences,
  • Such a foundation does not require maintenance, with proper observance of the device technology, the pillars practically do not change their position.

Method 4. Combined Pillars

This method differs from others in the participation of another component - a metal or asbestos-cement pipe. It will work as an insulator of logs from the ground for the same purpose - with the exception of direct contact of the ground and wood to maintain the strength of the support. How to install:

  • 1) A pipe at least 1 meter long is buried in such a way that about 15 cm remains above the surface of the earth.
  • 2) The soil is poured back into the pit along the outer diameter of the pipe and compacted thoroughly.
  • 3) The log is selected so that its diameter is slightly larger than the diameter of the pipe. At the base of the column, a cut is made of a length of 30-40 cm, cutting a diameter smaller than that of a pipe by 5-10 mm. Work requires high precision and accuracy. The result is a support with a lower base narrowed under the inner diameter of the pipe.
  • 4) The trimmed area is impregnated with an antiseptic or drying oil and allowed to dry.
  • 5) After drying the drying oil, the end of the column is closed with hot tar and put into the pipe. If there are gaps, they are also filled with this polymer.

The connection of the pipe and the column can be carried out before instillation, there is not much difference, matters in the convenience of the implementation of actions.

Additional security measures

Processing wood with an antiseptic and waterproofing before being buried in the soil does not guarantee the safety of the pillar during its useful life. A few simple tips will help you increase your service life:

  • The aerial part of the support is recommended to be painted every 3-5 years in order to renew the peeling paint,
  • Antiseptics can be replaced with ordinary oil paint, which leaves no chance for microflora,
  • Before applying paint to the surface of the wood, it is advisable to primer the base. This will help create a long-lasting coating effect with additional wood impregnation.
  • If the pillars are not concreted, it is advisable to diagnose them every 5-7 years in order to identify the processes of decay and marriage in work. It is often cheaper to troubleshoot than to change structural elements.
  • The most exposed and water-absorbing part of the column is the top. A large number of wood channels are located on the cut; therefore, water and humidity are intensively absorbed in them. Specialists recommend purchasing special metal covers for each support. They are made in different versions, you can choose the right products for your site or facade of the house.

The manufacture and installation of wooden supports for the fence is available to every developer, regardless of the experience of construction business. It is enough to have the necessary set of tools in the arsenal and you can begin to independently assemble the wooden fence.

Features of the installation of wooden support poles in the ground

Всем известно, что в наружном верхнем слое почвы содержится большое количество влаги, которая под действием капиллярного эффекта постоянно подымается из нижних слоев земли, поэтому ниже глубины 50-100 мм она никогда полностью не просыхает. High humidity in constant contact with oxygen in the air contributes to the development of putrefactive bacteria, and thereby has a destructive effect on wood.

In order for each owner of his own site to be able to provide reliable and durable installation of such structures, then the reader will be offered a detailed instruction that describes in detail various methods of protective wood processing and presents a simple technology for installing wooden poles.

The installation scheme of a wooden pillar in the ground.

Material selection and preparation

The quality of installation, as well as the strength and durability of the wooden support column installed directly in the ground, largely depends on the correct choice of wood and the proper implementation of preparatory work.

In order to cope with this simple task, you must be guided by the following rules and recommendations:

  1. The most durable material is larch wood, since it has a dense uniform fiber structure, therefore it is practically not susceptible to decay and damage by insects by pests.
  2. Oak and beech wood are also considered no less high-quality, however, the relatively high price of these materials makes it inappropriate to use them for such purposes.
  3. As an optimal option, treated pine logs can be considered, since its wood is impregnated with natural resin over its entire thickness, and besides, it has a low cost.
  4. The relative humidity of the wood before installation should not exceed 20%, and if the tree is more damp, it should be dried under a canopy in the open air for several months.

The photo shows blanks for wooden posts.

When choosing a material, you should also pay attention to the prepared logs being cleaned of bark and not having through knots, cracks, and also traces of damage by putrefactive and mold bacteria along the entire length.

Antiseptic and moisture protective treatment

Regardless of which wood was chosen for production, before digging a wooden pillar into the ground, it must be sharpened on all sides at the bottom and bevelled at the top end so that the wood fibers do not break when clogged with percussion instruments. After that, they need to be slightly burned in the flame of a gas burner or, in extreme cases, over a regular bonfire.

After all the logs have been prepared, they must be treated with one or more of the following formulations to protect them from moisture and destruction by harmful microorganisms.

  1. From modern means, various impregnations for wood-based wood, which contain antiseptic and antifungal substances, are well suited for processing the above-ground part of the column.

High-quality antiseptic impregnation for outdoor use should also provide protection against ultraviolet radiation.

  1. For many years, used automobile oil mixed with cable lubricant, which contains antiseptic additives, has been used as a reliable protection against moisture and is designed to protect against hemp core cores of steel cables. Before treating a wooden pillar in the ground with a similar composition, it must be warmed up and applied hot.
  2. For processing the underground part of the column, as a rule, thick compositions are used, which, after solidification, leave a thick protective film on the surface of the wood. The simplest option for such protection is to immerse the bottom of the log in molten resin or hot bitumen.
  3. As an alternative, you can use the application of several layers of liquid automotive rubber bitumen mastic for wood, followed by heating and drying of each layer with a building hair dryer.

Regardless of the method chosen, such protection of wooden poles from rotting in the ground should be carried out in such a way that after installing the logs in the ground, a layer of frozen resin or bitumen should be at least 100 mm above the soil level.

Installation of vertical pillars in the ground

When performing construction or landscaping work on a suburban area, the self-installation of wooden poles in the ground does not present any special difficulties, and can be performed by one or two people in a short period of time.

  1. First of all, it is necessary to mark the territory, and in a designated place using a garden drill to drill holes in the ground with a diameter two times larger than the thickness of the log. The recommended hole depth should be slightly larger than the freezing depth of the soil, but not less than 1/3 of the length of the column.
  2. At the bottom of each hole, pour a layer of crushed stone with a thickness of 50 mm, then install all the columns on the crushed stone and check that their upper ends are at the same height. Height adjustment is carried out by adding or removing a small amount of crushed stone.

Schematic illustration of the installation process.

  1. Each pillar should be installed strictly vertically, and fixed in the pit using temporary struts, controlling its position using the building level in two planes.
  2. After all the wooden poles in the ground are installed and set to level, you should backfill the hole, alternating crushed stone or small brick fight with excavated soil. After every 300 mm of backfill, it must be shed with water and rammed with a wooden beam or log.
  3. Without reaching 150 or 200 mm to ground level, stop backfilling with soil, pour a little gravel and pour concrete plug in the remaining hole, which will keep the column from swinging moment, and also protect it from the penetration of surface and rain water.

Protective concrete plug.

In marshy or low-lying areas, for additional protection against moisture, before installation, the lower part of each column must be tightly wrapped with roofing material and fixed in several places with a soft knitting wire.


When carrying out construction or installation work on a suburban area, you should be aware that protective earthing in a wooden house with your own hands should be carried out exclusively using steel pipes, in strict accordance with the requirements of the electrical installation rules, therefore, such work should not overlap with the installation of wooden support posts.

More detailed information on this issue can be obtained by watching an educational video in this article or by reading similar reference and information materials on this site.