What combinations are offered for the BILKA Matte metal gutter?

The BILKA Matte metal gutter has 30 Shopify variants: 2, 3, or 4 m lengths, 125 or 150 mm cross-section, and five matte RAL colors 7016, 7024, 8017, 8019, and 9005. All five colors are available for each length and both cross-sections. For example, 2 m / 125 mm / RAL 7016 is SKU LT-1290, and 4 m / 150 mm / RAL 9005 is LT-1289. It is useful in quantity calculations to group sections separately by length.

What is specific about the matte coating of the BILKA gutter?

BILKA publishes for the matte system a double-sided coating of 40/40 µm, zinc layer 275 g/m², UV category RUV4, and corrosion category RC5. This is a different surface category from the glossy 35/35 µm and RUV3. These characteristics do not mean that scratches, improper cutting, or incompatible fasteners are irrelevant. The color is chosen based on a physical sample because the same RAL code on screen can look different on matte and glossy coatings.

When is the BILKA Matte gutter 125 mm suitable and when 150 mm?

The official guide recommends 125/90 as a general minimum choice for roof areas up to 100 m², draining to the corresponding downpipe, and 150/100 for areas over 100 m². This is a guideline, not a substitute for hydraulic verification. Important factors are rainfall intensity, number of downpipes, gutter length, and roof slope distribution. The 125 mm gutter is combined only with 90 mm pipe elements, and the 150 mm gutter with 100 mm.

How to choose lengths of 2, 3, or 4 m for the BILKA Matte metal gutter?

Lengths are distributed according to the actual straight sections between corners, ends, and funnels, so there is a minimal but serviceable number of joints. BILKA allows a 2-3 mm gap at joints for thermal movement. For example, a straight line of 7.8 m can be planned as 4+4 m with a final adjustment if the hook positions and connector allow it. Only total linear meters are not ordered; a scheme with separate sections and flow direction is required.

At what distance are the hooks placed under the BILKA Matte gutter?

Hooks are installed every 60-90 cm, and an end hook is placed approximately 10 cm from the edge. On both sides of each internal or external corner, BILKA requires one support. The line is set with a slope of 3-5 mm/m towards the funnel. The exact distance depends on the base and local load; the published range does not justify lack of support at joints or corners. The fascia board must be solid and straight before installation.

How is the BILKA Matte metal gutter maintained after installation?

The main periodic care is cleaning leaves, deposits, and objects that obstruct drainage, as well as checking the funnels and downpipes. Immediately after installation, metal shavings must be removed because they rust and leave stains on the matte surface. During inspection, connectors, end caps, slope, and areas around hooks are checked. Abrasive cleaners and wire brushes are not suitable for the polyester coating; follow BILKA’s instructions.