The ValkGreenTop is made up of several unique components that are perfectly aligned with each other and stand out for their functionality, quality, and ease of installation thanks to our many years of experience, in-house R&D, and proprietary factory. Together, these components form an innovative and reliable screen system you can build on, now and in the future.
ValkGreenTop | Saving energy with an outer screen
The climate inside a greenhouse is easier to control when certain weather factors can be ‘screened out’ before they enter the greenhouse. Keeping sunlight out, for example, reduces irradiation and keeps temperatures down, which is especially important when growing premium ornamental plants such as orchids and roses.
On top of that, outer screens also help keep power consumption down, because they reduce cooling needs and increase CO2 concentrations thanks to less ventilation loss. And thanks to outer screens’ insulating effect, considerable energy savings can even be achieved over the winter months.
The ValkGreenTop outer screen by Van der Valk Horti Systems sits on the greenhouse’s ridge, which keeps the gutters clear and prevents dirt from accumulating. The lightweight structure is weatherproof and compact, which minimises light interception.
✔ Lightweight✔ Compact✔ Less cooling✔ Less heating✔ CO2concentrations
What makes the ValkGreenTop unique?
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The ValkScreenProfile VGT is the basis of the system. What is characteristic of this system is how well it withstandsall the weather conditions that an outer screen has to endure.
The screen cloth for this system is fixed to the screen profile using stainless steel cloth clips.
Unique design for installation outside the greenhouse. Equipped with chambers at the top and bottom for easy installation of ValkWireGuides. Available with 45mm diameter. Available in various standard lengths.
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The ValkBraceBar is based on the ValkPushRods that have been the standard in push rods for greenhouse ventilation mechanisms for decades.
With the ValkGreenTop screen system for outside the greenhouse, they are used as screen beam braces installed in a reverse V configuration on the ridge next to the roof rods. The V braces are hinged both at the top and at the bottom.
Any sideways swinging is absorbed well. No extra load on the ridge thanks to torsion of the structure. Made entirely to the customer’s specifications.
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The ValkWireGuide VGT makes sure that the profile and polyester wires can move independently from each other, so that no load is placed on the structure in case of expansion and shrinkage.
Compact design. Easy to attach in the upper and lower part of the ValkScreenProfile. Prevents wear of the ValkScreenProfile. Prevents light loss thanks to black stripes on the screen cloth.
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The ValkScreenClip VGT is fixed to the edge of the profile and does not have to be changed when changing the screen cloth.
Special weatherproof design. Provides ample cloth storage capacity. Minimum package size for maximum light gains.
ValkScreenDrive: The right screen drive system for any Venlo greenhouse
With three different drive types to choose from, you will always get the right system for your greenhouse!
Semi-pull/push drive system
Cost-effective and compatible with any type of greenhouse
Without a rack
No load on greenhouse gables
How does it work?
Works using the pull/push tube and steel pull wire.
Combines the benefits of a pull/push system with those of a pull wire system.
Unique ValkScreenDrive Type 3 components (semi-pull/push)
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The ValkDriveTube pulls and pushes the screen to open and close it.
Galvanised Contiflo tube, prevents white rust. Suitable for heavy duty (such as with darkening or shading cloth with opened ventilation windows) Available in two diameters: 27mm and 32 mm. Available in standard lengths. Easy to fix to any make rack. Reduced coupling with flange nut/flange bolt link.
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The ValkTableClamp is the ideal connection between the ValkDriveTube and the ValkScreenProfile.
Available in versions for a 27mm and 32mm tube. Extra strong bond thanks to hollow profile. Easy and solid installation with only one bolt.
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The ValkRollerBracket guides the ValkDriveTube.
Simple installation. Use of patented plastic rollers. Freedom of movement of the rollers effortlessly absorbs expansion differences between steel suspension tube and aluminium screen profile.
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The ValkDriveShaft is located in the centre of the screen section. The shaft winds and unwinds the steel wire to open and close the screen.
The ValkDriveShaft is available in three versions: x-reduced, o-reduced, smooth.
X-reduced shaft: easy to couple using a bolt connection, without play and without welding! O-reduced shaft: easier to weld together than the smooth tube. Smooth tube: can be welded together.
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The ValkWireTensioner is used in combination with the ValkWireSleeve. The tensioner makes sure the stainless steel pull wires are always tensioned correctly for correct functioning of the screen system. The sleeve ensures the pull wire winds and unwinds neatly.
Suitable for installation on the 2” drive shaft. Steel cable attached on the inner side of the tensioner to prevent it from damaging the screen cloth. Design guarantees a firm bond and steady alignment on the ValkDriveShaft. Grooves on the ValkWireSleeve guide the pull wire. Holes on the ValkWireSleeve indicate when the right number of windings has been reached.
Read what our partners say about their experiences with our company and our systems.
We can, of course, tell you all about how great our product is, but we prefer to leave that to our partners, who have been using our systems for years.
Downloads
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Brochure ValkGreenTop
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Promotional video | ValkGreenTop Screen System - Project Ter Laak Orchids
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Instruction video | ValkBearingBracket
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Certificate ISO 14001
