Roller shutter
A roller shutter (plural: shutters , rare blinds ), the Swiss Standard German and the store or the blinds , the Swiss Germans mostly Store (s) (mask.), Austrian in the business scrollbars , is a roll conclusion, as additional is completing a hole.
It is usually installed from the outside in front of a window or door and, depending on the version, can fulfill various protective properties, such as soundproofing, burglar resistance , thermal insulation , privacy protection. Technically, it resembles a roller door .
history
The origins of the shutter are rooted in simple shutters made of wood . Such shutters were already used in Roman times and served as privacy screens. In the 18th century, the French developed blinds that were initially rigid and later retractable using straps (pull-type blinds). In a further step, blinds were developed that could be rolled up using a shaft (roller blinds). This is how today's roller shutter emerged.
As early as the 18th century, roller shutters made of fine wooden strips were used on high-quality furniture (e.g. by David Roentgen ), for example to lock the writing compartment on a secretary. The use on furniture is still occasionally found today, especially on filing cabinets in offices, where the contents are often used during the day, open folding doors (which protrude into the room) or sliding doors (which always only reveal part of the cupboard), but it is a hindrance would be.
Since 1961, today's roller shutter and sun protection technician trade (formerly roller shutter and blind construction) has been carried out in Germany by the Bundesverband Rollladen + Sonnenschutz e. V. represented. The roller shutter and sun protection technician trade is also responsible for external and internal sun protection such as awnings , venetian blinds, external venetian blinds, shutters, rolling grilles, roller shutters, darkening, insect protection, internal shading as well as associated drives and controls.
Components
Roll armor
The roller curtain or roller shutter curtain consists of roller shutter slats connected to one another (also called roller shutter profiles). It is the protective part of the roll closure that closes the opening. Depending on the requirements, it can be made differently. The most commonly used materials are
- Plastic , mainly hard PVC ,
- Aluminum , often foamed with polyurethane ,
- Wood, usually pine,
- Steel or stainless steel .
The roller shutter slats are available in different dimensions. A distinction is made between left and right rolling tanks. In order to distinguish these, you have to imagine the roller shutter from the inside on the left. If the shaft rotates clockwise when it is rolled up, it is a right-hand roller, the other way round a left-hand roller. The most frequently used profiles are double-walled, with the exception of wooden profiles and the rare single-walled aluminum profiles, and some are filled with foam, which means greater stability.
The bars, with the exception of wooden shutters, are pushed into one another. In the lower part of the curtain (usually ¾ to ⅔ the curtain height) profiles are provided with light slots. With them you can regulate the incidence of light and the ventilation almost continuously. The rear ventilation of the roller shutters is important in summer so that no heat accumulates between the window pane and the roller shutter. The roller shutter curtain is prevented from being drawn into the rolling space by stop plugs on the end rods or an angle end rod. When operating the motor, the end point is set on the motor, depending on the motor type, so that the stop is not required. Modern motors have an end point detection so that no setting of the motor is necessary. As a result, the roller shutter can no longer open, e.g. B. on patio furniture.
The armor must be secured against moving the individual bars, as this can impair its function. This can be prevented by clips or locking pieces, which are attached on both sides of every second rod and protrude slightly beyond the width of the rod so that the rods can no longer be pulled apart. When locking the pins, small steel pins are placed in the bars that connect the profiles. This locking is not entirely unproblematic, as the pins can loosen over time. Mostly, locking pieces are used for aluminum and steel profiles, power clips and clip locking for plastic profiles. Depending on the type of roller shutter, sheets ("roll area cover" or "deflector plate") can also be placed on the side of the boxes.
PVC
PVC rods are light, inexpensive, offer the best thermal insulation and are easy to care for. Disadvantages are their flexibility, which limits the range of use (up to 2 m without reinforcement) and the lack of burglar resistance. Standard colors are white, gray, beige or wood colors, but modern plastics also offer many additional colors such as blue, yellow and red. Fast yellowing is now prevented by additives in the formulations.
When used as sun protection, plastic roller shutters should never be closed completely, but should always be placed on a light slot so that rear ventilation of the roller shutters is guaranteed. This simple measure can prevent the roller shutter from warping due to excessive heat. The roller armor becomes harder as it ages.
aluminum
When it comes to aluminum bars, a distinction is made between roll-formed and extruded aluminum armor. Roll-formed profiles have thin walls and are therefore generally filled with foam to give them sufficient stability. Because they use less material, they are lighter and generally cheaper than extruded profiles. Extruded profiles have thick walls, which makes them safer and more stable, but also more expensive and heavier than roll-formed ones. Often these armor are hollow, sometimes they have a PVC insert in the chamber or are filled with foam. They are used, for example, in security roller shutters. Foamed aluminum rods have good sound insulation . When coordinated with the entire roller shutter and in combination with a push-up protection, they offer good burglar resistance, are quite resistant to bending, weather-resistant, but also relatively expensive and heavier than PVC armor.
steel
Steel armor is very stable and heavy, which makes it interesting as protection against break-ins. This is also their main area of application, as they are very expensive compared to foamed aluminum armor.
Wood
Wooden shutters are not pushed into one another, but chained together. Before they can be used as roll-up armor, they must be protected against the elements. To do this, glazes and varnishes are used . They can be used up to a large width and offer good burglar resistance, but are also very expensive, heavy, require a lot of maintenance and are susceptible to weathering. They do not have any light slots, but can be made with an extendable chain. Since wooden shutters are made from renewable raw materials, they are highly recommended from an ecological point of view. Today they are only manufactured by a few manufacturers. Old rod shapes are also produced for use in monument protection , so that historical wooden shutters on buildings from the Wilhelminian era or Art Nouveau can be restored and missing parts can be added true to the original.
Guide rails
The guide rails are used to guide the roller curtain laterally and to divert external forces acting on the curtain, such as wind pressure. They are usually U-shaped and made of the materials already mentioned. In the past, hinged rails were also common, which, when folded out, steered the roller shutter outwards at an angle, today they are only rarely used.
Box and roll area cladding
The roller shutter box is an enclosure around the roller space, in which the roller curtain and shaft are located in the raised state. Sufficient thermal insulation is very important for the boxes provided on site (chip boxes, prefabricated boxes) .
Chip boxes are made of chipboard that is lined with insulating material. Since they are adjusted, insulated and fastened on site, it is difficult to achieve really good thermal insulation because there are often gaps in drafts and uninsulated surfaces. Therefore, prefabricated boxes are mainly used nowadays in new buildings. These are usually U or L-shaped and are fully insulated from the start. Boxes that are attached directly to the window as part of the window (top boxes) are mainly made of plastic with an inner lining made of insulating material. Front-mounted boxes that sit in front of the window or on the brickwork are usually made entirely of aluminum and do not require any thermal insulation, as they are located outside the heated envelope. Older roller shutter boxes can also be sealed and insulated.
wave
The roller shutter shaft is the part of the roller shutter which carries the roller shutter and on which the roller shutter winds. The roller armor is attached to the shaft by means of suspensions or special rails. The most common shaft used today is an octagonal steel shaft. However, there are also round shafts and hexagonal shafts, both made of steel and wood. Different diameters are offered, including 40 mm, 60 mm and 70 mm. When making your selection, you should pay particular attention to the dimensions recommended by the manufacturer, otherwise problems with winding and the bale diameter could occur. Reinforced steel shafts can be used for heavy roll armor. The deflection of the shaft may be a maximum of 1/500 of the shaft length, otherwise the problem-free winding of the armor cannot be guaranteed. Since the steel shafts are hollow, tubular motors can be used with them , which are inserted into the shaft. There are also spring shafts in which there is a spring that is tensioned when the armor is lowered, so that only small forces have to be applied when pulling it up.
Drive and operating elements
There are different methods of operating a roller shutter. When pulling a belt, a belt strap is wrapped around a belt pulley that is located on the shaft and then fed into the living area. When you pull on the belt, the shaft rotates and the roller armor winds up on the shaft. Due to its own weight, the armor unwinds when you let go of the belt. So that the armor stays in its wound position, there is a brake in the belt winder that holds the belt in place. The tensile force on the belt must not exceed 150 N. In order to reduce the effort, it is possible to use a gear instead of a belt pulley. As a result, however, the belt strap to be pulled becomes longer in accordance with the transmission ratio of the transmission. The belt must be straight, otherwise it wears out quickly. With light roller shutters, instead of the belt, you can also use cords that can be led around corners. However, you can use less force on these.
A similar system with a steel cable and a crank can be used for very heavy roller shutters. Due to the large gear ratio on the crank , only a small force has to be applied in such systems.
In the articulated crank gear, there is a gear in the roller shutter box that is connected to the shaft. This leads to a crank handle via a square steel bar. When the articulated crank is turned, the shaft is set in motion.
The most convenient type of drive is the tubular motor . It is pushed into the shaft and turns it. There are tubular motors in different strengths and rotation speeds. The end positions at which the tank should stop can be set on the motor. There are also motors that are controlled by radio, but an electrical connection to the power grid is always necessary. In connection with time switches , the roller shutter can be activated automatically, e.g. B. at certain times, can be started up and shut down. An additional sun sensor enables a shutdown when the sun is shining in order to prevent the room from heating up. The roller shutter can be closed in the evening using a twilight sensor or a timer. This simulates an inhabited house. In addition, the automatic lowering of the curtains in winter ensures that as little heating energy as possible is lost through the windows.
Functions
A roller shutter can fulfill different functions depending on the design.
Thermal insulation
When properly installed, a roller shutter can reduce heat loss from the window or door. The thermal insulation depends on the material, the shape and the thickness of the curtain. More important, however, is the depth of the air gap between the roller shutter and the window. In addition, the tightness of the roller shutter, especially between the armor and guide rails, must be guaranteed by piping and brushes. To ensure that as little outside air as possible gets into the roller shutter box, the roller curtain must be pressed against the lintel by the suspensions (steel springs).
Additional insulation of the roller shutter box can be achieved by installing sealing strips on the box's outlet slot. Even when the roller shutter is open (roller shutter curtain pulled up), cold air can largely be prevented from entering the box. With older roller shutter models, an audible improvement can also occur acoustically. The correct inspection cover is also important for the roller shutter boxes. With modern plastic lids (which should not and must not be papered over), a significant improvement in the insulation in the box area can be achieved. The choice of the right inspection cover determines the insulation level of the roller shutter box system.
Summer heat protection
By shielding the solar radiation, the wooden roller shutters can protect the room particularly effectively from heating up in summer, depending on the material. Plastic roller shutters or metal blinds, on the other hand, heat up comparatively strongly when the sun shines continuously, radiate the heat to the interior and may require air conditioning . That is why wooden shutters should preferably be installed on the south side of a building.
Sunlit roller shutters protect against heat if at least the light slots remain open. Otherwise, the trapped air between the roller shutter and window will heat up to very high temperatures. The additional heat enters the room through the window glass.
Soundproofing
The level of soundproofing of a roller shutter depends, among other things, on the material of the roller curtain and the distance between the curtain and the window pane (the larger, the stronger the soundproofing). If the distance to the window pane is too small, the roller shutter can even amplify the sound . With simple roller boxes, the sound through the box can cancel out the effect of soundproof windows. Attention should be paid to tight-fitting seals and adequate insulation of the roller box. By attaching sealing strips (profile with flexible and heat- or cold-resistant sealing hose) to the outlet slot, older roller shutter models can also be optimized in terms of sound technology.
Another soundproofing aspect concerns the noise generated when the roller shutters are pulled up or down. In particular in the case of large apartment buildings with many windows, it can lead to annoyance for the neighbors.
Wind and weather protection
Roller shutters can prevent drafts or rain from occurring when windows do not close completely. The effects of the weather on windows and window frames are reduced. Plastic roller shutters offer protection against hailstorms, but larger hailstones can break the outer shell in the event of a direct impact. It is therefore advisable to leave the plastic roller shutters open in heavy hail.
Burglar resistance
The plastic roller shutter offers virtually no protection against burglary , as it can be destroyed within a few minutes by cutting or burning through. For proper burglar resistance, the armor should be made of aluminum, wood or steel and the guide rails should be made of aluminum or steel. The roller shutter curtain must be secured against being pushed up. The resistance classes RC1 (hardly any burglar resistance) to RC6 (high burglar resistance) are assigned to tested roller shutter systems (in accordance with standards EN 1627–1630 or ÖNORM B 5338). Motor-driven roller shutters can only be pushed up a short distance because the gear motor blocks the axis. In addition, some roller shutter models are equipped with so-called quick connectors. They fix the roller shutter curtain firmly on the shaft and withstand a pushing force of over 1000 Newtons. This makes it much more difficult to pry open the roller shutter. Some of the roller shutter boxes have a locking groove which - when using spring clips - presses the roller shutter curtain against this groove when closed and achieves the same effect as with a motor-driven roller shutter.
Privacy and light protection
The roller shutter serves as a privacy screen in the dark and enables a room to be darkened in daylight. It can also act as sun protection - similar to a roller blind .
Daylight roller shutters that block the sun completely in the upper part but have intermediate parts in the lower area that allow a view to the outside are useful for office buildings. If the roller shutter is completely lowered, these gaps are closed. In another variant, the blinds are turned up as soon as the slats are pushed together (blinded roller shutters). This also ensures a view of the surroundings. Last but not least, there is the option of displaying the roller shutters, which also provides indirect lighting via the ceiling.
Installation types
There are various installation options for roller shutter systems.
Conventional installation
The roller shutter box sits above the window or door as a so-called lintel box . It is usually covered from the outside by clinker brick or plaster . The roller shutter curtain visually disappears into the masonry . This method is used in most new buildings today. Subsequent installation involves an unrealistically high level of effort and is therefore rarely done.
Top roller shutters
The box sits on the window frame as part of the window or door. This type of installation is often used when the windows are renewed. The disadvantage is that the height of the actual window and thus also the window area is reduced, which can destroy the look, especially in old buildings with arched windows.
Surface-mounted or front-mounted roller shutters
The roller shutter system is an independent, closed system. The box with guide rails is attached either to the masonry in front of the window or door or in the reveal . Front-mounted roller shutters are often used for later installation in the house, as they are very easy to retrofit. Because there are no cavities above the window with this installation variant, the formation of cold bridges (condensation water on the inside of the roller shutter boxes with the result of possible mold formation) is completely avoided, however, depending on the size of the roller shutter box, visibility may be restricted. Front-mounted roller shutters can visually enhance a house with careful selection.
Redevelopment
In many buildings, old roller shutters are installed in windows and glass doors that still fulfill their original function, but no longer meet the requirements of the current Energy Saving Ordinance (EnEV). The EnEv stipulates that standard structural requirements for the benefit of the overall energy efficiency of buildings must be complied with, both in new buildings and in the renovation of old buildings.
The thermal bridges that arise in the boxes of older roller shutters can be insulated through professional renovation, which leads to a better overall energy efficiency of the building and prevents the formation of mold. Molds develop particularly on interior walls, the temperature of which is below 12.6 ° C. If a roller shutter box is not insulated, this critical temperature of the inner wall will quickly fall below this critical temperature due to the high heat loss and mold will develop. After the thermal bridges have been insulated, with an outside temperature of −5 ° C, the temperature at this critical internal point is 13.2 ° C. The reduced release of heat to the environment ensures, on the one hand, better energy efficiency and, on the other hand, prevents the formation of mold. With consistent insulation in the area of thermal bridges, it is now possible to reduce heat losses by up to 56 percent with modern materials.
See also
Web links
- Federal Association for Roller Shutters + Sun Protection V.
- Guilds and regional associations in the roller shutter and sun protection technician trade
- Roller shutters and sun protection mechatronics / in the Berufenet the Federal Employment Agency
Individual evidence
- ↑ roller shutters. In: duden.de. Retrieved December 25, 2018 .
- ↑ Scrollbar. In: duden.de. Retrieved December 12, 2016 .
- ↑ Energy Saving Ordinance Guide for Residential Buildings ( Memento from February 26, 2015 in the Internet Archive ) (PDF)
- ↑ Burglary protection. Riha GesmbH, accessed on December 4, 2014 (information page of a commercial provider about burglary protection standards).
- ↑ ZAE study by the Central Institute for Applied Energy Research in Würzburg ( Memento of the original from November 13, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. .
