What is the purpose of the BILKA drainage nozzle at the bottom end of the downspout?

The BILKA nozzle forms the final outlet and directs water from the vertical pipe away from the facade and foundation or towards a prepared drainage channel. In the official diagram, it is the separate discharge elbow, not the upper offset elbow under the eaves. The element is installed after the final pipe elevation is determined. Its direction should match the terrain and planned water reception without causing dampness at the base.

Which size BILKA nozzle is suitable for a 90 or 100 mm pipe?

A 90 mm nozzle is mounted on a 90 mm downspout in a 125/90 system, while the 100 mm version fits a 100 mm pipe in a 150/100 system. The size follows the pipe part, not the gutter diameter. A transition from 90 to 100 mm is not used only at the last element. Before ordering, check the diameter, coating, RAL color, and how the water will be received on the terrain.

How many color options are there for the BILKA drainage nozzle?

Shopify lists 36 variants: 18 each for 90 and 100 mm diameters, divided among Matte, Gloss, and "Zinc." For example, 90 mm / Matte / RAL 8017 is SKU LT-3848, and 100 mm / Zinc is LT-3871. The full code is important because the lower nozzle may be visible on the facade. The color should be matched by sample, not just on screen, especially for an existing system from an older batch.

Where is the last bracket placed relative to the BILKA drainage nozzle?

The BILKA installation page places the last wall bracket immediately before the final outlet element. This way, the lower part of the pipe and nozzle are supported and do not stress the connection during wind or accidental impact. The exact height is chosen according to the terrain and reception point. The bracket should not obstruct nozzle insertion, and the lower opening remains accessible for inspection and cleaning.

Are the BILKA drainage nozzle and the 60° elbow under the eaves the same?

The two elements have different roles in the official system. The 60° elbow is used at the top to connect the gutter box to the vertical line or to offset towards the wall. The drainage nozzle is the final elbow at the bottom and directs water to a drainage channel, pavement, or other reception point. It should not be ordered based on an approximate photo; confirm the name, diameter, and SKU of the specific element.

Can the BILKA nozzle direct water directly to the building foundation?

The outlet should not allow rainwater to collect immediately next to the foundation or wet the base. The official guide allows final discharge outside or connection to sewage via an appropriate system detail. The solution depends on terrain slope, drainage channel, inspection chamber, and frost protection. The nozzle only sets the direction; it does not replace a drainage design and does not by itself ensure safe absorption of large water flow.