- Which greenhouse to choose
- Design and location features
- Installing racks
- Roofing system
- Why plastic wrap
- Fastening the film
- Ventilation device
- Making a door
- Summing up
With the onset of spring, an active gardening season begins. City dwellers flocked to summer cottages and vineyards to cultivate their hundred square meters. The villagers also took up shovels.
The seedlings are already growing, and soon it will be time to plant them in the ground, but immature plants need protection from cold spring nights. And everyone wants to quickly feast on early vegetables grown in their own beds. An urgent need to build a greenhouse.
Which greenhouse to choose
Depending on many factors, the design of the greenhouse will have its own distinctive features..
First, you need to decide for which plants you are building a greenhouse. Different cultures require their own specific conditions of detention, often incompatible. For example, cucumbers and peppers love a warm, stuffy and very humid environment, while tomatoes and eggplants are hot, but well-ventilated. It is clear that the structures for them need different, taking into account the differences in temperature conditions, moisture intensity, methods of care. Some plants have a high stem and are vigorous, they will also need an appropriate height, while for growing, for example, greenery, this issue is not fundamental..
Secondly, you should decide whether your greenhouse will be winter or “spring”, which is operated in spring, summer, autumn. The location of the building depends on this (west-east or north-south).
It is advisable to build a winter structure with a long side facing south, with a large slope of the slope, a deaf, dark-colored northern wall. Sometimes it is made reflective and tilted to direct the rays to the soil. Coating materials use the most transparent and preferably the least heat-conducting, with a decent margin of safety – cellular polycarbonate; several layers of dense stabilized polyethylene, which is reinforced, bubbly, with foam layers. You will have to think about the options for heating and additional lighting in advance.
Third, greenhouses can be designed for soil and soilless, hydroponic farming. They can be industrial and “summer cottage”, temporary and stationary, vegetable and seedlings.
The main thing is that the greenhouse reliably performs its main functions – it allows you to maintain the set temperature and humidity..
Next, we will consider how to build a lean-to spring greenhouse, in which it is planned to permanently grow cucumbers, peppers, greens, and maybe something else.
This is what we will build
Design and location features
As the simplest in construction and very advantageous in terms of heat engineering, the design with one slope was chosen. We orient it with a slope to the east, so you can collect the greatest amount of solar heat in the morning..
With an overall size of 5.5 by 3.5 meters, the greenhouse is placed with its long side in the north-south direction, in the expectation that it will be best illuminated by the productive rays of the morning and evening sun, and on a hot afternoon it will be easier to shade the plants, avoiding critically high temperatures.
As a material for the frame, we will use wood, which is easy to work with, it is well cut, it is easy to attach the film to it. With a reasonable approach, wooden structures are very durable and strong. In addition, observing a certain “culture of installation”, they are quite aesthetic. And the low price distinguishes this material favorably from plastic and metal, especially non-ferrous.
According to the specified dimensions, which is 5.5 by 3.5 meters, we mark the walls of the structure and pull the cords low from the ground. To maintain the rectangularity of the structure, it is necessary to measure the length of the diagonals – they must be equal.
Now, with the help of a shovel or a hand drill along the long side, after about 800 mm, we make holes with a depth of about 300 mm.
Well with crushed stone
We arrange the frame racks from a pine beam with a section of 100×50 mm. Each rack, that part of it that will be in the ground, should be abundantly smeared with bituminous mastic and wrapped in polyethylene – this will protect them from decay. If desired and financially feasible, it will not hurt to treat the above-ground part of them with special protective impregnations or drying oil, since it will be very humid in the greenhouse.
We put pillars not yet cut in height along the cord, and fill the well with medium or fine fraction with crushed stone, gradually tamping it. It fills voids very tightly and stabilizes the timber well. It is already worth using the long building level, although later adjustments will still be required.
Corner posts in a strictly vertical position are fastened with braces from the slab from the bottom of adjacent beams.
Arrange the racks
On the short sides, the posts are placed at a distance of 1150 mm from each other. In advance, a doorway of at least 800 mm wide should be formed on one of them, for the free passage of a garden wheelbarrow (700 mm). To arrange the entrance, we retreat slightly from the high angle so that it is possible to make it of an acceptable height.
When the pillars are in place, the cutting lines of the beams can be marked. Under it, horizontal struts are screwed to the racks, from the inside of the future room, with which the pillars are fastened along the level from the already rigidly fixed corners.
Now the timber can be sawed off. On the high side of the slope, the height is taken to be about 2100 mm – cucumbers will live in this part of the greenhouse. On the low side, the height of the tines is limited to 1300 mm, which is quite suitable for working with low-growing crops such as peppers, herbs. Close to the high part of the building, opposite the entrance, there is a conveniently located path. Note that the actual usable height of the greenhouse will be 100 mm higher due to the roof.
Racks in place
To eliminate some weakness of the structure in the middle of the long sides, it is advisable to install an auxiliary stand, from the bottom of which another brace is mounted.
Auxiliary post in the middle
On top of the pillars, rafters are installed, made of timber with a section of 100×50 mm and a length of 4.5 meters. They are attached to the uprights with galvanized metal corners using commonly available 35 mm “black” wood screws.
Rack and rafters
To save money, using scissors for metal from scraps of “drywall” profiles, you can quickly make a lot of budget corners and plates perforated with a large nail.
On the high side, all the rafters are connected from the end with a powerful bar, which is screwed with large hundredth self-tapping screws on wood “through the body”. It will serve as the basis for attaching the film along the ridge and eliminate the last parasitic vibrations of the structure.
Installing and unfastening rafters
Small crossbars are nailed between the rafter legs and long posts, stabilizing the formed acute angle.
At the bottom of the slope, the rafters are not cut to length, this will somewhat complicate the installation of the film, but they can be used as a frame for the device in the future of a small seasonal greenhouse for seedlings.
Why plastic wrap
The choice of polyethylene as a coating is due to many reasons..
Unlike glass, the film transmits ultraviolet rays, which are also necessary for plants, it scatters light, which is also very useful.
Light transmission is not the most important factor for our spring greenhouse, although the glass is only 10-15% better in this regard, and even then it is perfectly clean, which does not take very long.
The financial question will undoubtedly be in favor of polyethylene, given the price of glass, which is not eternal and quite often breaks and breaks. If the budget allows, then it is best to use polycarbonate for these purposes – it is preferable in all respects.
In our case, stabilized large-format polyethylene with a thickness of 100 microns will be used..
Fastening the film
First, we cut a strip of film 6 meters long, enough to cover the roof and the low wall of the greenhouse. It is important that there will be no polyethylene connection at the bottom of the slope, so there is no need to put jumpers between the rafters, which can delay the flow of water.
Next, we dissolve the film sleeve and we get the width of the canvas 3 meters, with it we cover three roof spans at once, having at the same time a margin for convenient fastening on the ground.
The main pressing of the film to the frame is carried out with thin meter strips. The polyethylene must be tightly tightened and nailed through the shingle with thin 20mm nails. It is better not to finish off the heads of nails – this will allow in the future to dismantle and replace the coating with minimal losses.
At the bottom of the canvas, they are securely fixed to the racks and sprinkled with earth.
If you have to arrange the coating alone, a construction stapler will help a lot for temporary pretension. The main thing is that they can work with one hand, while the other remains free. A quality staple gun nail down even thin slats, not to mention pneumatic or electric models.
One of the main problems that one has to face when growing vegetables in a greenhouse is the removal of excess heat. In summer, in the sun, the temperature inside the cultivation structure can reach 60 degrees, especially in the upper part, despite the fact that the mark of 40 degrees is destructive for most crops.
Opening doors and rolling the film from below on the walls do not give the expected effect, but only create a draft that carries away precious moisture. Cucumbers do not like him so much. It is better to play with the shading of plants with various curtains, or spray the polyethylene with a solution of clay, chalk.
Therefore, at the very top of the ramp, we will install four opening transoms from old glazed windows. We fasten them with small canopies from the ridge into the overlay with the roof. Our windows have small vents that can be opened in spring.
It is believed that the optimal ratio of the transom area to the total area of the greenhouse by floor is approximately 1: 6 or 1: 7.
There are several options for automating the opening of transoms. They are based on the use of an electric, hydraulic or bimetallic drive with the possible use of temperature sensors. This is very convenient – you do not need to constantly monitor the degree of air heating inside the greenhouse and constantly manipulate the vents, however, the costs also increase significantly.
Making a door
We make the door from a dry lath with a section of 30×40 mm. With the help of corners and plates, a light frame, fastened with braces, is assembled 10 mm narrower than the doorway in width and height. It is covered with foil and canopies mounted to the rack with outward opening.
A porch is made from the same rail on the opening, on which a rubber seal can be attached closer to winter.
It is imperative to make a threshold. It will make it possible to avoid the penetration of cold air from under the door and raise it above the ground, making it easier to open freely in the presence of an “unfavorable” slope of the site or snowfall.
The door must be equipped with handles on both sides and some kind of closing mechanism (spinner, bolt, hook …).
Such a structure is being erected by one person within 16-17 hours of leisurely thoughtful work.
From a power tool, perhaps, you can do without problems with a jigsaw and a screwdriver.
The total cost of a house for vegetables came out in the region of 4500 rubles.
The following materials were used:
Beam 100×50 90m.p.x 30 2700 rbl. Stabilized film 55 m2 x 12 660 rbl. Croaker 1.5 m2 x 45 67.5 rubles. Shingles 50 lm x 2.4 120 rbl. Rail 30×40 20m.p. x 7.5 150 rbl. Bituminous mastic 60 rbl. Crushed stone 150 rbl. Fasteners (nails, screws, corners, etc.) RUB 300. Delivery of materials RUB 300.
As you can see, to make a comfortable, problem-free greenhouse of this size (5.5×3.5 meters) it is not at all necessary to invest serious funds. You just need to make a little effort, and it will definitely bring a good stable harvest to its owner from the earliest spring to the late autumn frosts..
Done. You can plant seedlings
Obviously, some issues of the internal arrangement of the structure remained “behind the scenes” – these are automation, irrigation options, artificial heating, heat storage systems, features of the organization of space, the nuances of caring for greenhouse plants and many others. However, these are already topics for another article..