Types and causes of freezing of wells. Features of their thermal insulation in preparation for winter, the need for such work and methods of their implementation. Well insulation is a simple measure to avoid freezing of the water source in winter. If this happens, many homeowners immediately face many serious problems. For information on how to insulate a well with your own hands, read our today's material.
Varieties of wells
Wells of personal plots differ from each other by the type of construction and their purpose. They can be conditionally divided into three groups:
- Water supply wells … Such structures are located in farms where there is no running water or it is not possible to connect it to the house. The well in this case becomes the main source of drinking water.
- Technical wells … They are designed to accommodate and maintain engineering communications nodes.
- Plumbing wells … These structures serve to collect wastewater or act as cesspools. Their distinctive feature is the presence of a septic tank.
Different materials are used to insulate the above structures.
The reasons for the freezing of the well
Before insulating a well, it is important to understand the reason for its freezing to such an extent that the water in it turns into ice.
There are several reasons for this:
- Lack of insulation on the walls of the mine at the time of the end of its construction.
- The boundary of the aquifer is located above the level of soil freezing. The liquid takes on the subzero temperature of the upper layers of the soil and therefore freezes.
- The top of the well is open. In winter, frosty air freely penetrates the water surface and forms an ice crust on it. With an increase in the temperature difference between cold air and water, the thickness of the ice increases.
- High thermal conductivity of the shaft material. If brick or reinforced concrete was used during its construction, water freezing in winter in an uninsulated well will be rapid. It is not for nothing that krynitsy were made from logs in the old days. Such structures, even without insulation, practically did not freeze through due to the unique properties of wood.
The need to insulate the well
All-year-round wells, which are mainly available from rural residents, are insulated even at the construction stage. But similar sources of water, usually operated by summer residents only from spring to autumn, are often equipped without thermal insulation. And this can cause a whole series of unpleasant consequences:
- Freezing of water in the well begins much later than the outside temperature drops below 0 degrees. Usually, the initial signs of ice crust formation appear when the frost is -15-20 degrees, and the higher the water in the source, the faster it will freeze.
- The most obvious problem created by the ice crust in the well is the inability to draw water from it. Even a thin layer of ice a couple of centimeters thick can be a serious obstacle, since it will hardly be possible to break it with the help of a bucket.
- Another unpleasant feature of freezing water is its volumetric expansion. The ice plug can press on the walls of the shaft with a force capable of breaking the joints of its elements or causing cracks in the structure.
- If there is equipment in the well, the formation of ice can damage, for example, the pump or cause its hoses to crack. This is the reason for the warming of water meters - the effect of freezing temperatures on the delicate mechanisms of their meters will most likely lead to a decrease in the accuracy of the instruments.
As you can see from this list, there are more than enough arguments regarding the benefits of winterizing a well for the winter. Therefore, it will be correct to devote time and small investments in order to avoid many problems later.
Well insulation methods
There are three ways to insulate a well: thermal insulation of its cover, upper ring, and construction of a house above the neck of the shaft. Below we will consider each of these methods separately.
Well cover insulation
The technology of such insulation is not particularly complicated. Its meaning is to install an additional cover into the cavity of the shaft at the level of the ground surface.
For work, you need to prepare: plywood, wire and glue, PVC pipe, insulation 50-80 mm thick and polyurethane foam.
The process of warming the well cover should be carried out in stages:
- From a sheet of plywood, you need to cut two circles with a diameter corresponding to the internal size of the well shaft. In each of them, a pair of matching holes should be cut. One pair will be designed to feed the water pump hose to the bottom, and the other for the PVC ventilation pipe. Ventilation in this case is extremely necessary, since in a tightly closed mine, water can eventually acquire a musty aftertaste. The diameter of the holes should be about 60 mm, it is advisable to drill them from one edge of the cut out circles. Along the circumference of the future cover, slightly stepping back from its edge, 4 holes for the wire should be drilled in one of the plywood blanks.
- Now you need to cut another circle of the same, but this time from the foam. After that, the insulation must be fixed with wood glue on the lower plywood blank, and a second circle must be glued on top of it. When the glue dries, insert a ventilation pipe into the prepared holes. Polyurethane foam is suitable for sealing joints.
- At the final stage of warming the well with foam and plywood, it is necessary to make a ring from the wire for removing and replacing the manufactured cover. To do this, you need to wrap it with wire around the circumference and fix the resulting ring on the lid with ties using four previously drilled holes in it. Then the hose of the water pump should be passed through the hole prepared for it and the finished cover should be lowered into the well to the level of the ground line. Thermal insulation will be held in the mine thanks to the wire, ventilation will be carried out through a PVC pipe, the water in the well will not freeze.
Well ring insulation
Insulation of the upper ring of the well in order to prevent it from freezing can be performed using materials based on foam or polyurethane. Consider both options for such thermal insulation.
To insulate the well rings with polystyrene or its derivatives, it is necessary to prepare insulation plates, waterproofing, polyurethane foam and paint before work. The amount of materials should be calculated taking into account that the entire upper ring will be insulated, and the one that is located below - partially.
The procedure is as follows:
- First, you need to dig in the well around the circumference or around the perimeter, freeing its walls from the soil. You should get a trench with a width of 30-40 cm and a depth below the mark of its freezing in winter.
- The adhered soil residues from the rings should be removed and proceeded to pasting their outer surface with polystyrene, expanded polystyrene or polystyrene foam. Insulation sheets must be placed as close to each other as possible. The adhesive can be liquid foam or polyurethane foam. Using the same materials, it is necessary to close up all the gaps between the sheets of thermal insulation. When the well is insulated with penoplex, the gaps may be absent altogether, since its slabs have tongue-and-groove joints.
- The glued thermal insulation needs to be protected from moisture and salts in the soil. Therefore, after installation, the insulation must be covered with paint from the outside, and then, when it dries, wrap it with roofing material or other waterproof material.
- At the final stage of the work, the cavity between the edge of the trench and the well must be covered with expanded clay or gravel, and a clay lock should be arranged on top, which will prevent the penetration of water from the soil surface to the well insulation. The clay layer should be about 40 cm thick.
To insulate the well rings with polyurethane foam, you will need dowels, wooden blocks, collapsible steel formwork, film, plaster mix and a spray gun.
The work should be done in the following order:
- As in the previous case, you need to open a trench around the well, but less wide - up to 10 cm. Then, on the wall of the ring outside, along the circumference, you should install bars in increments of 40 cm.
- The edge of the trench must be covered with formwork, fixing inside it with a polyethylene film to prevent adhesion of liquid polyurethane foam to metal sheets. If this is not done, then it will not be possible to remove the formwork.
- The cavity obtained between the formwork and the wall of the well must be filled with insulation using a spray. During the filling process, the polyurethane foam will expand in volume, forming a dense, seamless insulating coating.
- When the insulation is dry, the formwork must be removed, the insulation must be plastered and painted to protect it from ground moisture. The cavity in the place of the disassembled formwork should be covered with soil and tamped down.
A well, the rings of which have been insulated using any of the methods described above, is recommended to be additionally covered with a lid.
Important! It is recommended to spray polyurethane at a positive temperature of 15-30 degrees. In cold weather, the material does not expand much, dries slowly and has insufficient adhesion.
Warming house for a well
Building a house for insulating a well hatch is a relatively expensive, but simple way. In addition to the fact that such a house can reliably protect the neck of the structure from debris, cold and precipitation, it contributes to the creation of a favorable microclimate in the krynitsa. A small hut made of boards or a log house installed on it minimizes the risk of freezing its upper part of the walls. Therefore, ice formation inside such a structure is unlikely. Also, the house on the well is an excellent decoration of the site. Inside the structure, you can place a gate with a bucket or a modern caisson with a pump. The house can be built in this way:
- A trench should be dug around the neck of a concrete or brick well. Its depth should be about 30 cm, width - 50 cm, which is taken 20 cm more than the width of the planned log house.
- The bottom of the finished trench should be leveled and then tamped. After that, the trench must be covered with gravel.
- On the resulting blind area, it is necessary to lay the bar of the lower crown of the wooden frame. A bar with a section of 150x150 mm, treated with moisture-resistant mastic, is ideal. For additional protection of wood from decay, it is recommended to put a couple of layers of roofing material under the crown.
- The assembly of the rest of the log house must be made of profiled beams or rounded logs. The height of the log house depends on the size of the mouth of the well protruding above the ground. During the assembly process, jute tape should be laid between the rows of crowns: the presence of this seal will save time on caulking.
- The cavity between the neck and the walls of the log house must be filled with thermal insulation - expanded clay, foam, etc.
- When the walls of the house are ready, you can install the roof frame. To do this, it is enough to connect two pairs of wooden rafters with a ridge bar.
- The gables of the roof must be sheathed with boards. Then, in one of them, a door should be made, which is necessary to access the gate of the well or the pump.
- On the rafters, you need to mount a crate of slats or plywood and fix ondulin, slate or other roofing material panels on it.
A clear advantage of this design is its aesthetic appearance and the possibility of convenient access to water. To do this, just open the door.
Thermal insulation of a sewage facility, that is, a cesspool, is practically no different from the insulation of a well with expanded polystyrene, foam or similar materials. The only difference is the need for additional work on the thermal insulation of pipes transporting sewage waste from the house to the plumbing well. These works, like the insulation of the lid, should be done first. After that, the walls of the well are subject to thermal insulation, which must be performed in one of the ways described above. How to insulate a well - watch the video:
If the well was insulated with high quality, it will not create problems for its owners even in the most severe frosts. However, one should not forget about the thermal insulation of pumping equipment and pipelines - their uninterrupted operation is also extremely important. Good luck!
