GREENHOUSE ARCS: HOW TO CALCULATE THE LENGTH AND MAKE AN ARCHED GREENHOUSE UNDER THE FILM

Ability to build arched greenhouse do it yourself more and more often, gardeners and gardeners are attracted, despite the fact that these structures can be bought in finished form.

What are the advantages of choice, and what you need to implement the project?

Advantages and disadvantages of the design

Benefits The “arches” are obvious and undeniable:

its installation will cost cheaper and take less time, than installation of the greenhouse as "house";
good light. An order of magnitude higher than, for example, in cattle greenhouses;
stability and reliability. If the structure is properly fixed on the foundation, neither strong wind, nor heavy rainfall will not violate its integrity;
if necessary, greenhouse can always lengthenby adding missing sections;
as cover material can be used and polycarbonate, and film. The process of installing the latter takes a minimum of time;
hence another advantage - minimum number of stitches;
opportunity self assemble frame according to preliminary sketches or drawings;
easy transferred to another piece of land, if necessary.

Of course limitations this design also has. And learn more about them in advance:

limited choice of shelter materials. As mentioned above, this is polycarbonate and film. Theoretically, you can use glass. But technologically, it will be difficult to install it, hence another drawback - higher installation costs;
in an arched greenhouse, the angle of inclination of the walls may vary somewhat with respect to the sun's rays. And when on clear days the light reflects off the surface, plants receive less heat they need to growas well as energy.

What frame can I use?

Frameworks for arched greenhouses can be classified by type of material used, namely:

aluminum. Differ in long service life and unpretentiousness in leaving as they do not rot and do not rust. Additional staining is not needed;
wooden. Recently used less and less, because the material itself must be further processed before use, in particular - impregnated with special compounds against fungi, rotting, etc. If you make racks of wood with your own hands, you need to sheathe waterproofing material before Otherwise, the structure (arched greenhouse) will quickly become worthless and simply collapse;
from PVC. Also, like the aluminum frame, it is not amenable to the processes of decay, the negative effects of acids, chemicals, as well as other alkalis and fertilizers. Plus, it has an attractive, aesthetic appearance;
other metal frames.

The latter can be classified into the following groups:

frameworks from shaped tube. An arched greenhouse made of a profile pipe, built with its own hands (reliable withstand a large amount of precipitation in the form of fallen snow, rain), is collected quickly and does not need special care;

Note! If you build arched greenhouses and use a non-welded frame made of shaped pipe, the maximum load on it will be significantly less - up to 40 kg / m. sq. of snow.

of hat profile. Durable, durable, resistant to corrosion. Convenient to transport: polycarbonate sheets with a length of 2, 1 m. Easily curled into a roll. But such a frame can not withstand heavy rainfall;
from the corner. Very durable, withstands snow pressure up to 100 kg / sq m. The only disadvantage is the high cost.

Choose a material for the manufacture of arcs under the arch

Arches for greenhouses, made by hand, must comply with a number of parameters, namely:

easy to install;
have a long service life;
be comfortable to operate.

In this regard, the market presents products of the following types:

metal arcs for the greenhouse. Very heavy, but reliable. Install easily and quickly. Ensure high strength of the finished structure;
plastic arches for the greenhouse. Very durable and resistant to all sorts of weather phenomena (snow, rain);
PVC greenhouse arches - analogue of plastic models, although many experts try to allocate them in a separate category, and find single non-intersecting characteristics. But, by and large, both in terms of price and in terms of quality, they are identical.

The process of making arcs for the frame

Plastic arc

Method 1

We hammer stakes around the perimeter of the future greenhouse. note: they must protrude above ground level by 13-16 cm.
From above we install curved pipes.

Note! It is important to observe the interval between the arcs to eliminate their possible sagging. The optimal distance is 0.5 m.

Method 2

We select metal rods that freely enter the pipes.
Cut into (0.6 m long).
We drive in 20 cm into the ground, and 40 are left above the ground.
We put plastic pipes on metal rods.

Wooden arc

How to make a wooden arc for the greenhouse with your own hands? The most convenient way is to manufacture directly on the frame of a future structure or on a plane, according to a preselected pattern. Wooden arches must be carefully treated, do not have knots on their surface. Optimal thickness - up to 12 mm.
The photo below shows an arched greenhouse made of wood:

Wire arcs

You can even use 10mm wirewhich is most often sold in building markets by rings. You can cut it into equal parts with the help of the grinder.

PVC profile and fiberglass arcs

draw a bend on a flat surface or, if possible, create a pattern using simple wire;
heat the profile with a building hair dryer (recommended temperature is up to 180 ° C);
in the next step, gently bend the arc, according to the pattern.

Note! You can bend the profile without heating. But in this case it is important to ensure a stable internal voltage in it.

The arches made of steel

Very durable and reliablebut relatively expensive. To make them yourself, you need to use a welding machine. Production of steel arches for greenhouses should be carried out in the following order:

we measure half arcs and select a pipe with a length twice as long;
cut into 2 equal parts;
we define the pipe that will be the top of the structure. Directly to it we weld tees along the edges, and along the length - crosses (we observe an interval of 0.5 m);
to the pipe going to the top we weld the elements cut off with the help of a crosspiece;
weld two more tees to the arc where the doorway will be;
we weld all the arcs provided for by the construction, with the exception of the extreme ones, to the greenhouse walls;
align the greenhouse length;
we fix by means of a transverse pipe and 2 tees for door pillars;
Cover the frame with a film.

Drawing of the arch greenhouse from the profile pipe:

How to calculate the length of the arc for the greenhouse?

To calculate the optimal arc size for the greenhouse, first determine bed width. For example, take 1m. To calculate the arc for the arched greenhouse you need in the following sequence:

Equate the width of the future structure to the diameter of half the arc. In this case, the height of the greenhouse will be equal to the radius. I.e:
R = D / 2 = 1m / 2 = 0.5m.
Now we calculate the length of the arc, as half the length of a circle whose diameter is 1 m.
L = 0.5x * πD = 1.57 m.

If starting the project, it turned out that the optimal length of the arc is not known, as well as the part of the circle it makes, you can calculate the arc for the greenhouse using Huygens formula, which looks like this:

≈

2l - l 3

AB = L

AM = l

AB, AM and MB are chords.

The error of the result is up to 0.5% in case the arc AB contains 60 °. But this figure drops sharply if you reduce the angular measure. For example, for an arc of 45 °, the error will be only 0.02%.

Preparatory stage

Place on the site. Greenhouse must be oriented east to west: so you will provide more sunlight for the plants. For more information about the rules for the location of greenhouses can be read by clicking on the link.

Foundation type. If you intend to use the greenhouse only for the season, lightweight construction without a foundation will do. For spring-summer - the best option. In all other cases, you can choose:

strip monolithic foundation;
strip dot foundation;
ribbon prefabricated foundation of reinforced concrete blocks.

As for the depth of the bookmark, this parameter largely depends on the climatic conditions of your region.

Step-by-step instruction

Consider the simplest method of how to build arched greenhouses with a frame of PVC pipes and wood elements under the film with your own hands.

You need to prepare the following tools:

screwdriver;
drill;
cord;
scissors (although you can do with a knife);
welding machine;
plummet;
ax, saw;
chisel;
hammer;
wooden bars;
reiki;
nails;
self-tapping screws;
polyethylene film;
level.

Start off the construction of the structure must be directly from the end walls:

we bring down the wooden trapezoid frame;
fix the PVC pipe to it using a screwdriver and screws;
the manufacture of ends is carried out in accordance with the selected design plan. For example, the best solution for an average over the area of the greenhouse will be the ends of a width of 3.5 m, a length of 5 m, a height of 2.5 m;

similarly, the second end wall is made in the same sequence;

we cover both frames with foil. Cut it off with a margin for attachment;

we mount the rest of the structure. For this purpose we drive in reinforcement columns into the ground;
we set up the level of the columns and fasten to them the end frames;
we stretch the cord on both sides of the structure. This will allow the lateral edges to be set smoothly, without distortions;
on the sides of the end walls with an interval of 1 m we drive in reinforcement;
in the next step, we attach the arches of PVC pipes to it;

structural elements are fixed using wire anchors, as well as screws;

Cover the frame with plastic wrap, securing the ends on a wooden plank.

Conclusion

With your own hands, you can make greenhouses from different materials - from polycarbonate or from window frames, and various designs: arched (as described in this article), single-wall or double-gable, and also winter or home. Or you can choose and buy ready-made greenhouses, which you can read about in more detail in one of the articles on our website.

Of course, the construction of a greenhouse involves a certain amount of time and effort on your part. But if the design will be installed in compliance with all recommendations of experts, you will ensure high profits by large yields even in cold months.