Once upon a time, only a professional could make an arch. This was the case before the advent of drywall. Now, even a beginner can make an arch from drywall. You don’t need a special tool for this, the technology itself is simple and straightforward – just follow our instructions.
Where to begin
The most common arches are simple shapes – parts of a circle or oval. They are best suited for most traditional interior styles, where regular shapes and symmetry are welcomed. In addition, they are easiest to do with your own hands..
1. Classic rounded arch. 2. Modern. 3. Romance. 4. Ellipse. 5. Trapezium. 6. Semi-arch
But first you need to decide whether the height of the vault will be sufficient. And if for a niche in the wall dimensions do not play a special role, then for the passage between rooms, the ratio of the width of the arch and the distance from the floor to the point of conjugation of the arch with the wall of the opening means a lot.
The wider the opening in which the arch is formed, the greater the bending radius will be required so that the shape of the arch is proportional
Usually they are guided by a simple ratio of a standard interior door – 80–100 cm wide by 200 cm high. That is, in the plane of the opening, taking into account the arch, a rectangle of such dimensions must be inscribed in a “pure form”. Following this rule, you can determine that the width of the opening is:
- 100 cm corresponds to the height of the lower points of the arch about two meters;
- 200 cm – about 180 cm;
- 300 cm – about 160 cm.
It follows from this that if the arch is made where the standard interior door stood, then the height of the opening will have to be increased.
The easiest way is to arrange an arch in a new place during redevelopment, when the interior partitions are re-installed. And here it is already necessary to remember the recommended distance from the top of the arch to the ceiling – usually it is 40-60 cm. Often the height of the ceilings does not allow you to “fit” the arch in accordance with this rule, and this point is raised a little higher. But even in this case, you should not reduce the clearance to a ceiling level of less than 30 cm..
After the approximate values for the mating points with the opening and for the height of the arch have been established, the arch in the opening can be modeled from improvised means and make sure that it corresponds to the general design.
It is convenient to use a special plastic corner for arches, which will ultimately be used when decorating the opening
One easy way to model is to use a long strip of flexible material as a mold, such as a hard edged plastic skirting board. The plinth is applied with the edges at the lower points of the arched opening, bent to the height of the arch, if necessary, change the shape of the arch, adjusting the degree of bending. Mark the mating points of the arch with the opening and put the appropriate marks on the plinth.
For the walls of the arch, you need to cut out two rectangles from the gypsum board. The dimensions of the workpiece are the width of the opening and the distance from the mating point of the arch in the opening to the overlap of the opening itself (or to the ceiling for new partitions).
Then, on one of the blanks, using a plinth, the shape of the arch is modeled. To do this, aligning one of the marks on the baseboard with the corner of the workpiece, it is bent until the second mark is aligned in the corner of the workpiece opposite in width. Draw an arc on the workpiece with a pencil and cut out the first wall. And already it will serve as a template for cutting out the second wall.
To get a sector along the radius, it is better to use an awl, a nail and a pencil tied with a thread or rope. The length of the thread from pencil to nail will determine the radius of the sector.
L – opening width, H – arch height, R – sector radius, D – material stock equal to the thickness of the opening ends
If an ellipse is needed, then two nails are fixed on the workpiece under the arch along the long side, retreating the same distance from both sides by about 10-15 cm. A thread is tied to the nails so that it sags freely, and when pulled along the edge of the sheet it reaches its edge … The pencil is wound by the thread and the shape of the arch is outlined.
For the arch of the arch, you can use a strip of ceiling gypsum board (it is thinner, only 9.5 mm), but the remainder of a standard sheet is also suitable, since with a small width of the strip, it is not difficult to give it the necessary shape. The size of the blank for the vault in length is equal to the distance between the marks on the plinth, and in width – to the thickness of the wall in the opening. The narrow sides of the workpiece are cut at the ends along one side of the corner so that the arch fits more tightly at the ends of the walls of the opening.
Forming the arch frame
The supporting frame for the walls is usually made of a metal rack profile. Depending on the materials of the partition and its thickness, the profile width may vary.
So if the arch is mounted in an opening where the walls are made of gypsum plasterboard, then the same rack-mount CW profiles are used that are in the supporting structure. In this case, the profiles are fixed in the opening with self-tapping screws for metal.
For walls made of bricks, building blocks (gas or foam concrete, gypsum), monolithic concrete, the width of the rack profile is selected individually. It is often easier to use a double frame (for each side of the arch) from a narrow CW profile with a 50 mm backrest than to select a wide profile for a single frame. For fastening to the wall, dowels are used, and for each material they select their own type of fastener. If the frame is mounted from a narrow profile, holes for the dowel are drilled at an angle so that the edge of the opening does not crumble.
For side posts, the profiles must have a length equal to the distance from the overlap of the opening to the mating points with the arch. Since the arch “fits” in the opening to the partition at an angle less than 90 °, the lower corners of the profile are cut so that they do not protrude beyond the edge of the walls of the arch.
If the frame is mounted in a plasterboard partition, then you can clearly see how it should be fixed so that the arch is flush with the wall surface.
For partitions made of other materials, when fixing the frame, it is necessary to retreat from the edge of the wall by a distance equal to the thickness of the gypsum board plus the thickness of the finish (and this is at least 1-2 mm per layer of putty for wallpapering or painting).
If the wall has a layer of decorative plaster or is lined with wall panels, then the fastening of the frame must go to the main material of the wall so that the walls of the arch are in the same plane with the surface of the partition itself, and not its decorative finish. This rule is carried out on each side of the arch..
The walls of the arch are fastened with self-tapping screws with a distance between the attachment points from 15 to 25 cm, but at least three points on each side. The distance from the corner to each extreme attachment point should be within 5-10 cm, and the attachment line should be at a distance of 15-20 mm from the edge of the arch wall.
If a built-in backlight is provided in the arch, then the wires should be laid in advance, leaving leads or loops at least 15 cm long
After both walls are fixed, two strips of an arched profile are screwed to them from the inside through drywall to fasten the arch. If there is no arched profile, then it is made from a CD profile, symmetrically cutting wedges on the sides at a distance of 4-5 cm from each other.
To bend the strip of the workpiece with an arc, it is moistened with a sponge on both sides before installation. Then, on one side, they are rolled with a needle roller (another method is to prick with an awl over the entire surface by 1/3 of the sheet thickness) and once again moistened only along the perforated side. They are placed on the floor at an angle to it and the wall. When the workpiece begins to bend under its own weight, it is screwed into place to the arched profiles..
The final stage begins when the vault is dry:
- the surface of the drywall is primed;
- seams and joints with the wall are reinforced with a serpentine, and the ribs of the arch – with a plastic perforated corner;
- putty, rubbing the attachment points, seams and joints;
- Angles at the ribs are “taken out”;
- dry and grind.
The arch is ready. You can start decorative finishing.