Making the foundation for a greenhouse: choice of material and construction technology. How to make a foundation for a greenhouse - advice from experts Do-it-yourself columnar foundation for a greenhouse

For a strong greenhouse, it is necessary to build the right foundation. For summer construction it may be lighter, but for year-round cultivation it is necessary to take care of a strong foundation. The dimensions of the greenhouse and base depend on the width of the bed and plant placement options. It is important to take all this into account at the planning stage.

The choice of the optimal type of foundation depends on the material used to make the greenhouse, the available funds and the time and climate of the region. Greenhouses made of glass or polycarbonate require a stronger base. These can be strip or surface types of base. The method of installing them is similar, but the tape type requires a deeper trench.

Among the foundation materials, the popular use of wood, brick, and concrete. You can also use concrete blocks or slabs. Each material has its own characteristics of use.

Foundation types:

• Wooden beams;
• Concrete-brick;
• Concrete strip;
• Using blocks;
• Columnar;
• Pile;
• Monolithic.

The wooden base is light and accessible. The material used will be high-quality wood. You can use available materials; even using old window frames will do. But at the same time, there are also disadvantages of using wood - a short service life, when exposed to moisture it begins to rot, and is subject to the negative influence of fungus and mold.

But at the same time, you can get rid of all the shortcomings of wood if you pre-treat the beams with an antiseptic.

The concrete-brick base is lightweight and easy to install. At the same time, it is strong and suitable to create a warm foundation for a winter greenhouse. But this type tends to accumulate moisture and crumble.

The concrete strip foundation is durable and will last a long time. It is resistant to any aggressive environmental factors. But at the same time, it does not retain heat well, is quite heavy and difficult to install.

Using blocks is a cheap and easy option. It is resistant to the negative influence of external factors. But it has poor thermal insulation properties and low strength.

A columnar foundation has the necessary strength, durability and low cost. But the installation has its own characteristics and requires rigid fixation and insulation of the base. The same disadvantage applies to installing a foundation on piles. The use of a pile-screw design implies strictly vertical placement of sleepers. It can be moved if desired. But if the frame is metal, then the piles should also be made of this material.

The monolithic version is quite durable and has a long service life. It protects the soil well from weeds and pests. But at the same time, such a foundation is quite heavy and expensive. In addition, it is necessary to additionally insulate the base. It is also necessary to provide for the construction of a drainage system.

Rules for choosing the right foundation:

1. There is no need to build a greenhouse on a buried foundation. The soil will swell and deform the greenhouse.
2. The foundation should not be heavier than the greenhouse structure itself. Otherwise, over time the greenhouse will warp.
3. An insulated foundation is needed only for winter greenhouses.
4. In cold regions there is no need to use a brick and concrete foundation. It does not retain heat well, and under the influence of cold weather it will begin to collapse.
5. There is no need to build a common foundation for the greenhouse and residential building. Buildings have different loads.
6. Piles and shallow foundations are optimally used in climates with significant freezing of the ground.
7. For polycarbonate greenhouses, it is better to use a strip foundation, monolithic or using cinder blocks.

To build a reliable foundation, you must follow all the rules for building a foundation. Don't neglect useful advice. Before installing any type of foundation, the area must be prepared. To do this, the ground is cleared, leveled and marked.

Base on a wooden beam for a greenhouse

You can make a foundation on a beam by purchasing two types of wood. The first is deciduous or coniferous trees. Before work, they will need to be treated with an antiseptic. The second option involves the use of ready-made bars that have already been treated with the necessary substances.

Types of base on timber:

• Tape;
• Columnar.

Strip foundation is more popular. Its installation is simple and accessible to everyone. But at the same time it turns out to be a reliable and solid foundation.

Before installing any type of foundation, a number of preparatory work must be completed. These include clearing the land and creating markings using pegs and stretched rope.

After preparing the work site, it is necessary to dig a trench. Its size depends on the load on the foundation. Next we move on to installing the timber base.

Stages of installation of a wooden strip foundation:

1. The bottom of the trench must be lined with roofing felt to protect the tree from moisture;
2. Next you need to install the timber;
3. It is necessary to connect the corners together using self-tapping screws, nails, special supports or anchor bolts;
4. Next you will need to cover the base with roofing felt.

The columnar option is cheaper. After preparing the soil, you need to dig holes for the posts. The bottom of the excavation must be filled with sand and compacted, having first moistened it well. After this, the columns are mounted and covered with roofing felt.

Do-it-yourself concrete strip foundation for a greenhouse

After preparing the soil, a trench should be dug and reinforcement installed. For a winter greenhouse you will need to make a formwork for the base. Its height should be 30-60 cm. The trench must be covered with waterproofing material.

To create waterproofing, you can use ordinary polyethylene or geotextiles.

Next you need to do the reinforcement. Steel rods are stuck into the bottom and tied with thick wire. The length of one rod is 60 cm. 30 cm remain above the ground, the other 30 cm are plunged into the ground. Next you need to pour the concrete. Before this event, you can make a 15 cm sand cushion. In another option, 10 cm sand and crushed stone are used.

After pouring the solution, you must wait three days. After this, you can install the greenhouse. If the weight of the structure is large, then you need to wait 30 days.

How to make a monolithic foundation for a greenhouse

First, we prepare the installation site for the greenhouse and make markings. The top layer of soil will have to be removed and a pit dug. The depth of the pit is on average 30-40 cm. It all depends on the load on the foundation. The bottom of the pit must be covered with waterproofing material.

Stages of installation of a monolithic base:

1. Installation of footings. You need to pour concrete onto the sand and level the soil well.
2. The formwork needs to be secured.
3. It is necessary to cover the pit with roofing material.
4. Fastening reinforcement. You need to deepen the rods and wrap them together with wire.
5. Pouring concrete. You need to act quickly so that the solution has time to level out before the mixture hardens.

After completing all the work, you must wait until the foundation hardens. Every day you need to spray the base with water. After a couple of days you can install anchors. When the monolithic coating has completely hardened, you need to put roofing felt on top.

Before pouring concrete, it is necessary to consider the drainage arrangement. To do this, a waste pipe is installed in the center of the foundation.

You can handle all this on your own. You just need to sensibly assess your strengths and capabilities.

A strong foundation for a greenhouse made of blocks

The block base is suitable for building a greenhouse on an area with dry soil. Thanks to the blocks, a kind of monolith is created. It completely protects the greenhouse from the negative effects of the external environment.

Stages of constructing a foundation from blocks:

1. Mixing sand-concrete mortar;
2. It is necessary to build walls starting from the corners;
3. It is necessary to lay a cement cushion before laying the blocks;
4. Then you can put the first block, controlling its evenness;
5. It is necessary to cover the end parts of the block with a solution;
6. After the cement mixture has hardened, the seams need to be expanded;
7. Installation of anchors.

The thickness between the seams is approximately 1 cm. It is also important to take into account the dimensions of the slabs in order to calculate their number for the building. This factor is important to consider when creating a drawing.

Do-it-yourself greenhouse made from window frames without a foundation (video)

To obtain a harvest all year round or for a long-lasting greenhouse, it is necessary to equip the foundation. For an industrial structure, a more durable concrete base is provided, while for home greenhouses, a wooden base can be used. For a summer greenhouse, you can use a point foundation.

Examples of a greenhouse on a foundation (photo of ideas)

As you walk through the private sector of the city or a holiday village, look around: you will see all the variety of greenhouses located on the plots. At the same time, not only the types/materials of frames and covering materials will differ. If you look down, you will see that some greenhouses stand directly on the ground, and some are raised on a foundation, simple or with a plinth.

In this article we will consider the issue of the need for capital foundations for greenhouses and their types. It also provides step-by-step guidance on pouring a foundation for an ordinary polycarbonate structure.

Foundation for a greenhouse: necessity, types

Do you need a foundation for a greenhouse? And if necessary, which one? We will look at these questions below.

Foundation in a greenhouse: is it necessary?

The need for a foundation depends entirely on the type of greenhouse structure. For example, small arc greenhouses do not need it, since they are used only in the summer and are put away for storage in the winter. Also, without a foundation, portable prefabricated structures are built from metal profiles and polypropylene pipes. They are seasonal; permanent beds are not organized inside.

If the construction of a large stationary greenhouse is planned, the construction of a foundation will be mandatory for several reasons:

• A tall structure will sail heavily. Despite the heavy weight, there will always be a risk of the greenhouse moving due to a gust of wind.
• The frame raised above the ground is protected from constant exposure to moisture contained in the soil.
• The greenhouse space is reliably protected from the entry of pests moving underground - mole crickets, May beetle larvae, moles. The same goes for weed penetration.
• A recessed base for a polycarbonate greenhouse, insulated with your own hands, helps maintain greater energy efficiency of the building.

As you can see, the question “do I need a foundation for a greenhouse made of polycarbonate or wood” cannot be answered unambiguously.

Foundation for a polycarbonate greenhouse, photo of the strip version

What to put a polycarbonate greenhouse on? Different variants

First of all, we must say about polycarbonate greenhouses. Depending on their size and seasonality, they can be built on different foundations. For small summer greenhouses, a columnar base, concrete, brick, or block, will be sufficient. Sometimes the foundation for a greenhouse is made of polycarbonate from timber impregnated with antiseptics and hydrophobic compounds. It is simply a square/rectangular belt raised above the ground on bricks or concrete blocks. The fastening of the elements to each other is done by a combination of a steel angle and a half notch.

Lightweight polycarbonate construction

As for thermoses, there is no question about what is the best foundation for a polycarbonate greenhouse. They must be built on a strip, insulated base - concrete or lined with foam blocks. Sometimes the lower part (about 80 cm) is cast from concrete, while the upper part is laid out with aerated concrete. Occasionally, underground greenhouses are made on a monolithic foundation. Most often, this technology is used for industrial cultivation of vegetables, when the greenhouse area can reach 100 m2.

The foundation for a greenhouse made of foam blocks contributes to better heat retention indoors

How to make a foundation for a polycarbonate greenhouse: diagram of a strip system

Bases for wooden greenhouses

Wooden greenhouses are rarely made massive, so they usually have a columnar foundation underneath them. It can be filled with cement-sand mortar or laid out from aerated block or brick. The main thing is that the strapping beam is raised above the ground - this way the base will last longer. If you plan to make the greenhouse large-scale, then it is better to make a reinforced strip base for it.

Columnar foundation for a greenhouse, made of brick. Serves as a base for wooden structures

As for greenhouses made from window frames, it all depends on what type of frames they are. If they are modern, made of a metal-plastic profile, then we select the base according to the same principle as for metal-profile polycarbonate structures. This is due to the fact that plastic windows are heavy and have a long service life; they are usually used to make winter greenhouses.

How to make a foundation for a greenhouse with your own hands, photo of the foundation for a structure made from old frames

Construction of a foundation for a greenhouse

Preparing the work site

Like any construction, installation of a foundation for a greenhouse begins with preparing the site. The work is done like this:

• We remove stones, branches, and any debris.
• In several places we apply a building level to the ground. We smooth out uneven areas, tear off the bumps, and fill up the holes. If the surface is initially flat, simply remove a layer of turf over its entire area.
• We make markings for the foundation trenches. Referring to the drawings, we set up a system of pegs with crossbars along which we pull the cord. The marking should be double-circuit, as in the diagram below.

Marking the work site

Organization of a trench for the foundation, installation of reinforcement

The width and depth of the trench are determined by the size, weight, and materials used to make the greenhouse. We are describing the foundation for a typical polycarbonate greenhouse with a metal profile frame, so the parameters are accordingly:

• Depth – 50 cm.
• Width – 35 cm.

The given figures are correct for buildings with an area of ​​less than 7 m2; anything larger requires additional load calculations. They are carried out in accordance with SNiP 2.02.05-87. If the greenhouse is intended for winter use, along the edges of the ditch we immediately make formwork for the base - 30-60 cm high. The height of the formwork is determined by the size of the base + 15 cm. We line the trench around the entire perimeter with a moisture-proof membrane. This role is successfully performed by ordinary polyethylene film or any geotextile.

Trench covered with moisture protection

Despite the fact that a greenhouse weighs incomparably less than a residential or country house, the foundation for it must be reinforced. Only the armored belt here is made according to a different principle. It is much simpler than the reinforcement that we are used to seeing when looking at house building manuals. Everything is done very simply:

• Steel rods are stuck into the bottom of the trench along its entire length. The length of each is 60 cm, 30 go underground, 30 remain above the ground.
• We connect all the rods with thick wire. The piece should be taken as large as possible so that there are not many joints that would weaken the tie.

Reinforced belt for strip foundation

How to make a foundation for a greenhouse: pouring mortar

Next steps may vary. Some craftsmen consider it correct to lay only a sand cushion at the bottom of the foundation pits for greenhouses. It is poured in a layer of 15 cm and compacts well. Next, the armored belt is placed, and the pouring of the cement-sand-gravel mixture begins. The second option is 10 cm of sand + 10 cm of crushed stone, tamp it, lay reinforcement, and fill it.

The type of cement mortar depends on how massive the greenhouse will be. Typically, two types of concrete are used for pouring foundations:

• M100 – cement (M400) 1 hour, crushed stone 6 hours, sand 3 hours. After reaching full strength, it can withstand pressure of 100 kg/cm 2 .
• M200 – cement (M400) 1 hour, crushed stone 5 hours, sand 3 hours. Withstands pressure of 200 kg/cm2.

For most types of greenhouses, the strength of M100 concrete is more than enough.

Option for filling a trench for pouring

We pour the solution into the formwork so that about 5 cm remains to its edge, while the reinforced belt should be covered with at least 5 cm of the mixture. We work with concrete as quickly as possible so that it does not have time to set before it is evenly distributed throughout the trench. After pouring is complete, cover the formwork with concrete with film and leave it for three days.

During the specified period of time, the concrete will set, and it will be possible to begin installing the polycarbonate greenhouse on the foundation. The exception is industrial greenhouses, which are heavy. Here you will have to wait about 30 days for it to reach full strength. Otherwise, deformation of the base may occur.

Pouring concrete into formwork

The following video contains a story about how to make a foundation for a greenhouse from timber with your own hands. It is suitable for light greenhouses, prefabricated and stationary.

The construction of the foundation is a critical stage; the strength and stability of the structure largely depends on it. A greenhouse without a foundation is a structure that some summer residents erect on their plots from polycarbonate. Let's try to figure out how justified this construction option is.

A reliable foundation will be needed both for a ready-made structure purchased on the market, and for a building made with your own hands from scrap materials.

The article explains why a foundation is needed. In it you will find a photo of the foundation for the greenhouse.

The article addresses the question of what kind of foundation the structure will need depending on the chosen building material. Here are detailed instructions on how to make a foundation for a polycarbonate building.

Why is a foundation required to build a greenhouse?

Typically, a foundation is needed for a permanent structure, such as a house. As for light structures at the dacha, they are erected temporarily. Land owners cannot help but be interested in the question of whether a foundation is needed for a greenhouse at all.

There is only one possible answer here - there is no way to do without building a base. The base performs the following tasks:

• Provides reliable fixation of the frame, which is not afraid of strong gusts of wind or precipitation.
• Does not allow the structure to come into contact with the ground, thereby increasing its service life. The base allows you to retain approximately 10% of the heat.
• The base prevents cold air and fog from penetrating inside.
• Protects the structure with the crop from insect pests and rodents.

What are the types of foundations for greenhouse structures?

There are 4 types of foundations:

• tape;
• pile;
• columnar;
• slab

Knowledge of the specific features of the soil, topography, climate, and dimensions of the building will help the owner of the site decide what kind of foundation to build for the greenhouse.

Tape

The strip base is considered suitable for the vast majority of structures. Based on the principle of construction, there are several types:

• Not buried. It lies on a hard layer of soil. To do it, you will need to remove the fertile soil. This base serves as a grillage for a foundation on piles.
• Shallow. A trench is dug to a depth of 70 or 80 cm. A special pillow is prepared in advance for the base. This option is not suitable when groundwater is located close to the site.
• Recessed. It is recessed to a considerable depth. On average, the figure varies from 1.2 m to 1.4 m.

It is necessary that the cross-sectional height value exceeds the thickness or width value. The proportional ratio of the length of the structure in relation to the width is 1.5 - 2:1.

The optimal proportion for depth with height is considered to be 0.7:0.3-0.4 m. Materials for constructing a strip foundation can be concrete blocks, stone, clay, brick, foam blocks, concrete.

If the greenhouse needs a foundation that is cheap, then it should be built from timber. Special protective compounds will help make the base more durable, preventing the process of rotting.

Pile

A foundation on piles is an excellent option for constructing a greenhouse in wetlands or uneven areas.

• driving;
• screw.

The installation of a pile foundation requires less time than the construction of a strip foundation. The distance between the piles is from 1.5 to 2 m. The grillage of the building can be monolithic concrete. It can also be constructed from beams or sleepers.

Columnar

A columnar base is a budget solution suitable for small buildings. Such a foundation for a greenhouse will need to be deepened by 0.7-0.8 m with your own hands.

To construct a columnar base, you may need the following materials:

• brick;
• rubble stone;
• T-shaped concrete pillars;
• pipes made of metal, asbestos or roofing felt;
• foam blocks;
• wooden stumps.

To prevent cold from penetrating inside the structure, the gap between the ground level and the base of the building is sewn up with boards.

Slab

Slab foundation is a suitable solution for areas with unstable soil or high groundwater levels. There are 2 types of plates:

• floating;
• base with stiffeners.

A trench is dug under the slab to a depth of 0.3-0.7 m. Sand and crushed stone are poured onto the bottom, the cushion is leveled and covered with geotextile and roofing felt on top.

The thickness of the foundation is calculated depending on the purpose of the building. For a light greenhouse, 100 mm is enough, and for a large stationary greenhouse, 200 or 250 mm is required.

Building a polycarbonate greenhouse

The structure has its own characteristics. So, a strip foundation for a polycarbonate greenhouse is the best choice.

• You need to create a project. The drawing indicates the dimensions of the future structure and the main components. At this stage, you need to decide on building materials and their quantity.
• We choose a place for the construction of a greenhouse. Clears the construction site of stumps and debris.
• We are laying the foundation.
• It is recommended that the base rise 1/3 above the ground.
• attached to the base with anchor bolts.

After installing the greenhouse, it is important to seal the gap between the base of the structure and the foundation.

Photo of the foundation for the greenhouse

The foundation for a greenhouse is the basis that will ensure the stability, integrity, and strength of the building. Whether you build with your own hands or have the opportunity to buy a ready-made structure and carry out independent installation on the site, the site must be equipped in accordance with the specifics of the structure.

In the article we will tell you why you need a foundation, what is the best foundation for a greenhouse made of polycarbonate, glass, with a frame made of timber, for metal structures, light buildings made of boards, film, old window frames, etc. And we will provide detailed step-by-step instructions on how to make a foundation for a polycarbonate greenhouse with your own hands.

Why does a greenhouse need a foundation?

The foundation ensures the reliability, safety and stability of the building. But light structures on the site are temporary, so the question reasonably arises: in general, is a foundation made of polycarbonate or other materials needed for a greenhouse and why? The answer is clear – it is needed, it is a base that performs a number of important tasks:

• fixes the greenhouse frame, holds it during gusts of wind, heavy downpours, when the area is flooded and from other atmospheric surprises;
• isolates the structure from contact with the ground, protects materials from the harmful effects of the soil, significantly extends the service life of the building;
• helps retain up to 10% of heat inside, promotes a favorable microclimate and saves on heating;
• prevents fog and cold air currents from penetrating into the greenhouse;
• helps protect the structure and crop from harmful insects and rodents.

How to make a foundation for a greenhouse with your own hands, photo of a light structure on tape

Types of foundations for greenhouses

There are 4 types of foundations in total and each of them can be equipped for a greenhouse:

• tape;
• columnar;
• pile;
• slab

The choice of foundation depends on the specifics of the soil on the site, its relief features, the scale of the construction, climatic conditions in the region, and much more. etc. Next, we’ll talk in detail about each type of foundation for a greenhouse and the materials for its construction.

Tape

Strip foundation is the most popular base for almost all types of buildings. According to the construction principle, it can be:

• not buried - lying on solid ground, it is enough to remove the top, fertile layer, usually serves as a grillage for pile foundations;
• shallow - placed in a trench 700-800 mm deep, on a specially prepared cushion; such a device is not advisable if there is high groundwater in the area;
• recessed - recessed 200-400 mm below the soil freezing level, this parameter is individual and depends on the region, the average is 1200-1400 mm, exact information can be found in the table.

Foundation for a greenhouse made of bricks, diagram of the correct foundation

Optimal ratio, depth and height: 700:300-400 mm. Before making a foundation for a greenhouse, you need to decide on the materials for the tape:

• Monolithic concrete, consisting of a reinforcing frame and filled with mortar.
• The base is made of special ready-made concrete blocks interconnected by reinforcement.
• Rubble structure made of stones and clay.
• A strip of bricks, foam blocks, it is advisable to still pour a monolithic concrete base and build a base on it.
• Construction from scrap materials: thick timber, bottles, logs, etc.

Non-buried foundation for a greenhouse made of polycarbonate, made of timber on concrete supports

One of the inexpensive ways to install a polycarbonate greenhouse

Slab

A slab foundation is a strong, reliable foundation for construction in areas with high groundwater and unstable soil; pyramids in the sand have just such a base. The greenhouse can be installed on two types of slabs:

• Floating - a concrete platform lies almost on the surface.
• The base with stiffeners is a combined structure made of concrete strips, with a monolithic slab attached to them on top. If a strip foundation must necessarily be closed along the contour, then in the case of a slab this requirement is absent.

To organize the slab, a pit with a depth of 300-700 mm is dug, a sand-crushed stone cushion is laid on the bottom, covered with geotextiles, roofing felt, this helps to avoid siltation. The optimal thickness of the foundation depends on the expected loads: for outbuildings and light greenhouses - 100 mm, for large stationary greenhouses, designed for the winter period, 200-250 mm.

As a rule, a slab foundation for a greenhouse is made of concrete, but tires filled with earth and other available materials can be used.

Layout of the slab base

Columnar

A column foundation is a simple, inexpensive, quick way to build a foundation. The pillars are deepened by 700-800 mm; for small buildings they may not be sunk into the ground. The optimal distance between pillars is 1.5-2.0 m.

A columnar foundation for a greenhouse can be made from the following materials:

• Bricklaying, rubble stone.
• Use ready-made T-shaped concrete pillars.
• Install, reinforce and fill metal, asbestos and roofing felt pipes with mortar.
• Foam blocks, flat rubble stones, even wooden stumps are suitable for organizing a non-buried columnar foundation.

Pole arrangement diagram

A significant disadvantage of a columnar foundation for a greenhouse is the gap between the ground level and the base of the building, through which cold gets inside. Such conditions contradict the functionality of the building, so the perimeter should be insulated: make a brick frame, cover it with boards, etc.

Foundation for a greenhouse made of foam blocks, a high base will protect the timber from harmful influences

Pile

A pile foundation is an ideal solution for building a greenhouse on a swampy or uneven area. It is installed below the soil freezing level by 200-300 mm. There are 2 types of piles:

• driven - pipes, sleepers, channels;
• screw - poles equipped with blades that are immersed in the ground in a circular motion using a drill or special equipment.

The optimal installation of piles is 1.5 - 2.0 m from each other. After installation, the upper heads are sawn to size and tied together with a grillage, which ensures the integrity and strength of the structure. The grillage can be made of timber, sleepers or monolithic concrete.

Organization of a pile foundation for a greenhouse with a monolithic concrete grillage

Let's sum it up

If you choose bases for glass structures, film buildings, bases for structures made from old window frames, ready-made prefabricated metal structures, foundations for a polycarbonate greenhouse, which one is better, it is impossible to say with any certainty. You should rely on geodetic research, soil quality, dimensions and materials; the weight of the building and climatic conditions depend on them.

For capital warm buildings, it is recommended to make a strip foundation - this option is suitable for almost all conditions. Temporary and lightweight greenhouses, if you want to save money, can be safely installed on a point columnar base.

Internal structure of a strip base for a greenhouse

Foundation for a polycarbonate greenhouse - photo and step-by-step instructions

We will build a strip foundation for the greenhouse, size 3*6 m, with a high brick base and insulation around the perimeter.

Making a drawing

Before building a greenhouse, you should choose a project or make a drawing with your own hands, indicating the dimensions and main components of the structure. The materials, their quantity, and the main stages of work are also determined here. It is better to use a standard project and adapt it to your own conditions.

Typical ergonomic greenhouse design

Choosing a place

The choice of location depends on the individual characteristics of the site. It is better to build a greenhouse on the southern and most windless side, behind the house. We clear the site of debris, tree roots, and weeds. We fence the perimeter with pegs, tighten the rope, and check the geometry. The diagonals must be equal. Remove the top, soft layer of soil.

Foundation structure

We dig a trench 800 mm deep around the perimeter. Level the bottom. We cover it with roofing felt in 2 layers, you can lay geotextiles. We fill in crushed stone, sandstone, layers of 100-200 mm, and compact the pillow.

We install the reinforcing frame. There will be two horizontal belts, two parallel rods in each, vertical ties every 300-500 mm. The reinforcement is corrugated, with a cross section of 8-12 mm. We place pebbles, 50 mm high, or stands on the bottom.

We lay 2 lower horizontal rods, the distance between them is 200 mm, we lay smooth thin rods perpendicularly to better preserve the shape of the frame. At the corners we bend the reinforcement to the adjacent side, extending it to 500 mm or more. Also on the other hand, a double overlap is obtained to strengthen the structure. We drive in vertical rods and tie the parts together with wire. We mount the upper horizontal belt in the same way.

How to knit reinforcement correctly

The distance between the horizontal belts depends on the height of the foundation for the greenhouse. If the tape is 400 mm high, then there should be a distance of 300 mm between the upper and lower rods, +50 mm per concrete layer on each side. The width is calculated in the same way, if the total dimension is 300 mm, then the frame is 200 mm. Don’t forget, the height must be greater than the width of the tape.

We install formwork in the trench; these can be knocked together boards, moisture-resistant plywood, or durable plastic panels. For the correct geometry, we make a tie along the top of the sheathing with bars, and install spacers on the outside, they will hold the structure when pouring concrete.

The tape should be poured at once to avoid the formation of seams and cold bridges. Proportions of solution for the foundation for a greenhouse: cement (binder) - 1 part, sand - 3 parts, crushed stone, fraction up to 40 mm (preferably 10-20 mm) 4-5 parts, water 4-5 parts, until the consistency of thick sour cream. First, the dry ingredients are thoroughly mixed, then water is added.

The photo shows how to properly fill the base for a polycarbonate greenhouse with your own hands

Pour the mixture into the sheathing, tamp it, remove the air. Bubbles in hardened concrete will lead to destruction. The solution needs to harden, until it is fully formed - 4 weeks, only then load the foundation.

We remove the formwork, glue the sides with roofing felt or coat them with bitumen mastic in 2 layers, attach foam sheets on top, you can order insulation - sprayed polyurethane foam. We cover the top of the sheets with 2 layers of roofing felt, the seams overlap 100-200 mm, seal with tape, and weld with a blowtorch. We backfill the soil. For horizontal waterproofing, roofing felt is laid on top of the foundation under the greenhouse.

How to install a polycarbonate greenhouse on a foundation

Along the fresh concrete in the center of the tape, in the corners and every meter, it is recommended to install and extend out reinforcement for metal structures or special corners with welded anchors for fastening the bars; the greenhouse frame will be attached to them. If the mortgages were not provided during the process of pouring the foundation for the greenhouse, then the frame can be fixed with anchor bolts.

Method of attaching the frame to the foundation

Installing a polycarbonate greenhouse on a foundation has one more important step: in order to avoid drafts, ice, and freezing, the gap formed when the base of the greenhouse adjoins the foundation is sealed with elastic sealants, and a gasket with rubber edges is placed in the gap. This is especially important if the structure is insulated and you plan to grow crops in it all year round. When setting up a winter greenhouse, do not forget about additional lighting and heating.

Today, a greenhouse or hotbed can be found on almost any summer cottage or garden plot, and these are no longer homemade products from window frames, but quite worthy products from manufacturers made of polycarbonate.

Most often, such structures are advised to be installed on a foundation, which causes some confusion among summer residents. Why is this necessary? Isn't it easier to just assemble the greenhouse on bare ground without bothering yourself with any additional work? Still, in order to make a foundation for a greenhouse with your own hands, you will have to spend some time and money.

Is it necessary to make a foundation for a greenhouse?

Polycarbonate greenhouses have quite a noticeable weight, so their installation requires the manufacture of a foundation. The fact is that a structure installed directly on the ground is not only susceptible to corrosion, at least its metal parts, but it can also be washed away by groundwater or spring floods. And this leads to distortion of the greenhouse and its subsequent destruction.

Another option, when they dig into the ground, does not help either. Winters in Russia are cold, which leads to deep freezing of the soil, which, under the influence of heaving forces, simply squeezes the supports of the structure out of the ground. Therefore, for a durable and reliable installation of a greenhouse, you simply need to make a foundation for the greenhouse with your own hands, which will firmly fix the structure in a stable position.

What kind of foundation is used for a polycarbonate greenhouse?

How to make a foundation for a greenhouse with your own hands depends, firstly, on the type of soil on which you plan to install the greenhouse. Secondly, on the size, and to a greater extent, on the weight of the greenhouse.

Therefore, first of all, it is worth considering what kind of foundations are used for polycarbonate greenhouses, and then choose one of them. For all its dimensions, a greenhouse is considered not a particularly heavy and large structure, so it is still not worth making a solid foundation for a greenhouse with your own hands, such as a monolithic one. Although in some cases it is also used, but more on that later. The following are mainly produced:

• Point foundation.
• From ready-made concrete blocks.
• Made of brick.
• From timber.
• Monolithic base.

These are the most common bases, which are most often made as a foundation for a greenhouse with your own hands. Under polycarbonate, stable and even support is required, since when distorted, this material begins to become covered with cracks and becomes unusable, and the above listed bases fully provide the necessary static stability.

Point foundation

This type of foundation cannot even be called a full foundation; rather, it is supports for the greenhouse frame, but it has every right to use.

The main goal - to give stability to the frame - it fulfills. Moreover, the material used to make the posts is selected depending on the weight of the greenhouse: the larger it is, the stronger the material should be. For small greenhouses, scrap timber is used; for larger greenhouses, it is better to install concrete blocks.

Such a foundation for a polycarbonate greenhouse is made with your own hands only for use in the summer, since it does not retain heat. Another disadvantage is that insects, especially pests, do not encounter any obstacles on their way to cultivated plants.

But such a foundation can be made very simply and quickly: blocks or timber, from which low stumps are cut, are installed in the corners of the greenhouse and along the perimeter every meter. This type of foundation is a temporary foundation and can be easily dismantled when moving the greenhouse.

Wooden beam foundation

A timber foundation is another type of mobile foundation that can be easily disassembled, making it easy to move the structure to another site. Therefore, they make a foundation from timber for a polycarbonate greenhouse with their own hands in the event that a permanent location for the structure has not yet been chosen, and it will most likely be moved. In addition, the base is quite inexpensive, and installation takes no more than one day.

In addition, the tree provides the correct microclimate in the greenhouse due to its ability to well absorb excess moisture from the air and, if necessary, release it.

One of the disadvantages of using such a base is its fragility, since even wood treated with an antiseptic and water-repellent agent is subject to destruction. To make such a base, as a rule, 10x10 cm is used.

How to make a frame from a wooden beam?

Before installing the foundation for the greenhouse with your own hands, the surface of the area under the polycarbonate must be carefully leveled. To do this, remove the top layer of soil, level the area and dig a small ditch 10 cm deep and 20 cm wide along the perimeter. It’s good if the greenhouse has already been purchased and you know its dimensions, otherwise it’s time to decide on the type of greenhouse.

A cushion of crushed stone is poured into the bottom of the trench, which will drain excess water, or a layer of waterproofing is laid. They knock together a frame from timber, making sure to check the perpendicularity of the corners and the horizontality of the surface. The corners are strengthened using a construction corner.

The manufactured frame is treated with an antiseptic and lowered into a trench, the free space is covered with soil.

A similar foundation for a greenhouse made of timber can be made with your own hands from a smaller material, for example, 50x50 mm bars or 50x150 mm boards, if the structure is not particularly large in size.

Concrete block base

This type of foundation is more solid and provides good waterproofing of the structure, which is very important for maintaining optimal humidity in the greenhouse.

Therefore, the best option would be to make such a foundation for a greenhouse with your own hands on damp areas of land, on peat or swampy soils.

First of all, it is necessary to mark the plot of land on which the greenhouse will be installed. To do this, we level the selected area and mark the perimeter of the structure using pegs and rope.

Installation of blocks

After marking, it is necessary to dig a ditch 25 cm wide and 30-40 cm deep under the future foundation so that the marking cord runs exactly in the middle. A drainage backfill of crushed stone and sand 10 cm high is placed at the bottom of the trench, which is carefully compacted. To do this, the top layer of sand is spilled with water, and compaction occurs naturally.

Start the concrete solution and pour half of it into the ditch. Concrete blocks are laid around the perimeter, which must be leveled. Separate blocks are placed strictly in the corners. The remaining concrete is poured on top and smoothed with a spatula.

It is quite possible to make such a strip foundation for a greenhouse with your own hands in a few hours, and you can install the greenhouse in 2-3 days.

Concrete strip base

Another option for making a foundation for a greenhouse with your own hands in the form of a strip is to make it from concrete. At the same time, to strengthen the structure during pouring, reinforcement in the form of metal rods is laid.

If the soil is dense and not prone to crumbling, the concrete solution can be poured directly into the ditch. In the case of loose and friable soil, it is necessary to install formwork from boards in the prepared trench. Assembling the device is not difficult, the main thing is to maintain the verticality of the walls. The size of the formwork depends on the height of the planned foundation: if it is planned to be raised above the ground, then the walls of the formwork must be mounted to this height.

Concrete is poured into the formwork. If the prepared solution is not enough for one-step filling, it is poured in layers. At the same time, try to lay the concrete as evenly as possible, as this will extend the life of the foundation. The last layer must be leveled with a spatula.

Concrete-brick foundation

When properly manufactured, this type of foundation is second only to a reinforced concrete foundation in terms of strength characteristics. At the same time, brick has the same properties as wood; it absorbs moisture well, and this guarantees an optimal microclimate for plants.

On the other hand, this material is quite expensive and it is advisable to make a foundation from baked bricks only if it is possible to purchase such products inexpensively.

To do this, a concrete strip is made flush with the ground surface, as discussed above. When pouring, place anchors or pieces of metal reinforcement around the entire perimeter and wait until the concrete sets. After about a week, you can lay brick on the tape, and the reinforcement should be inside the masonry joints.

Monolithic foundation

Another type of foundation can be poured from concrete, which is usually used to install large greenhouses, glass greenhouses, or if the soil on the site has increased heaving. This option is used only in exceptional cases, since making a foundation for a polycarbonate greenhouse with your own hands in the form of a monolithic base is quite a costly undertaking, both in terms of time and money.

Preparing the area for pouring proceeds in the same way as for any other base. It is cleared of the top fertile layer of soil, after which a pit is dug for a foundation 30-40 cm deep, which is covered with geotextiles or any other waterproofing. If the soil contains a lot of water, you can make a small drainage system using trenches covered with pieces of roofing felt, or lay drainage pipes.

Pouring concrete

Formwork is made from boards and a layer of crushed stone and sand with a total height of 10 cm is poured into the hole with obligatory pouring for compaction. A reinforcement bundle is placed in the formwork and poured with concrete. If necessary, reinforcing bars or anchors are inserted to secure the frame to the base.

You can install a greenhouse on such a foundation only after the concrete has completely dried, which can last 21-28 days. At the same time, while the solution is setting, its surface must be periodically moistened to avoid the appearance of cracks and damage to the integrity of the base.

Although such a foundation requires a lot of labor and considerable financial expenses, its service life, which is about 50 years, more than compensates for everything.

In addition to these main types of foundation, several other types of foundations are used, for example, from a metal profile or on screw piles. Some craftsmen combine the above installation methods, and particularly inventive individuals can make a foundation for a greenhouse with their own hands from scrap materials, for example, from glass bottles.

What foundation should I use for a glass greenhouse?

It is worth mentioning separately about a glass greenhouse, which is also often used in summer cottages. Due to its characteristics, this structure is much more demanding both in terms of stability and protection from damage. Therefore, the foundation under one’s own hands is made mainly in the form of a concrete monolithic or strip foundation. Unlike the foundation for a polycarbonate greenhouse, the foundation for a glass structure must be buried to the level of freezing of the ground.

If the greenhouse is small in size, it is permissible to use a metal or point foundation. However, such a base will not provide sufficient thermal insulation, so the heat consumption in the greenhouse will increase. At the same time, it is not worth making a base from wooden beams, much less boards, for a glass greenhouse, since wood will not provide sufficient immobility for the structure.

From all of the above, we can conclude: the correct choice of foundation for your greenhouse depends on how long it will last.