End gable
The gable end always has a gable rail directly under the gutters. The other gable rods are located between these two rods. The exact number depends on the roof size. For example, an end gable with a 3.20 meter cap size consists of four glass strips per bay on average. All other bay sizes often contain five glass strips per bay, so here there is no gable rod right under the ridge, but next to the ridge. In the case of a half-glass end gable, twice as many rods are required.
Side gable
The side gable is relatively less laborious in composition and calculation since it has fewer specific requirements; after all, it has only one rod length.
Bottom rail
The design of the footer profile makes it possible to mount a facade on different foundation types such as poured edge concrete foundation, precast concrete slabs and sandwich panels. This profile can be used at both end and side walls. The footer acts as a base for the aluminum façade construction, as the façade rods are attached to this profile.
The bottom rails are connected at the corner of the foundation with a bottom rail corner piece. On the straight foundation parts, the toe boards are connected with a coupling.
Facade Rails
The gable rods are essential for proper sealing of the greenhouse because the glass is placed between these rods. In addition, the rods add structural strength to the greenhouse, especially at the corners of the greenhouse where more external forces (especially wind) occur. The gable rods are attached at the bottom of the gable structure to the base rail, through the stacking profiles to the steel purlins and at the top of the structure to the roof corner rod.
The glass is clamped into the 4 mm low rod facade system with PVC cover strips. In the high rod facade systems for 4 mm, 4 + 4 mm and 6 mm glass, it is possible to use screw and snap strips.
With the 4 mm and 6 mm system it is possible to apply an additional glass panel on the inside of the facade. This allows a higher degree of insulation to be achieved. Special facade rods have been developed for these insulating glass systems.
When choosing 4 mm glass, three types of systems can be chosen: two lighter and one heavier (stronger) system. The difference between them is made by the standard low gable rod, a weighted low gable rod or a high gable rod. We include in the system recommendation the gable rod that is most suitable for the load on the facade.
BOAL Systems carries a number of common standard lengths in its assortment of gable rod PVC cover strips. These PVC cover strips are therefore not project-specific delivered in every desired length. However, when purchasing a certain minimum quantity, this is possible on a project-specific basis.
Stacking profiles
In order to efficiently and quickly construct a high facade that is strong enough to carry and enclose heavy fixing materials (e.g. glass), stacking profiles are used on set glass sizes in the horizontal direction, between the facade rods. To increase the load-bearing capacity and strengthen against external loads, these profiles are attached to the steel gable columns.
Roof corner rod
The roof corner rod is only used at the end walls of the greenhouse and connects the cover posts with the gutter and ridge at the top of the sloping section. This roof corner rod also ensures proper rod placement and alignment. The cover plate at the gutter is also mounted against it. In addition, the roof corner rod is also the first rod on the deck. BOAL Systems has different types available for transitions to and from 4 mm glass, plastic channel sheets and ISO-Glas in the gable and on deck.
Guardrail
The gutter rail is only applied at the side facade and at the top of this facade it connects the deck rods to the first gutter row of the deck system. This roof corner rod also ensures proper rod placement and alignment. At the inner head gable, the flashing rod functions as the roof corner rod.
Air windows
To enable growers to naturally and cost-efficiently provide controlled ventilation of the greenhouse also at the gable end - with the aim, for example, of lowering the temperature or dehumidifying the climate - we offer various types of gable vents. The crop requirement and cultivation method determine the ventilation requirement and capacity of the greenhouse, so a particular type of air window will best suit.
All vents ensure maximum light penetration because they are composed of narrow, strong aluminum profiles. Also, the glass is securely and safely enclosed in the profiles; glazing these vents is easy and fast.
To ensure a strong facade, the application of a facade air window requires some specific adaptations compared to a "closed facade.
