Installing gutters and downpipes: the brackets, the slope and the joints

The gutters are installed before the roof covering. The brackets are set at most 80 cm apart, with the first and the last 10 cm from the edge of the roof, and are laid to a slope towards the downpipe. The downpipe is fixed to the wall with clamps, at most 2 m apart. Below are the installation principles of the BELPROFILE gutter systems, one by one.

What slope must the gutter have?

The gutter runs down towards the position of the downpipe. When the brackets are marked out, 2.5–5 mm is allowed for every metre of eaves. The slope is marked out before the brackets are installed.

How far apart are gutter brackets set?

At most 80 cm apart. The brackets at the ends sit 10 cm from the edge of the roof. The brackets are installed on the fascia board.

How to install the brackets

1. The drainage slope is marked out, towards the position of the downpipe.
2. The brackets are marked and bent, each according to its place on the slope.
3. The brackets are installed on the fascia board, at most 80 cm apart.

How to connect the gutter to the downpipe

1. The gutter is laid in the brackets and the position of the outlet is marked with a pencil.
2. A hole 85 mm in diameter is cut in the gutter with metal shears.
3. The edge of the cut-out is tapped gently inwards with a rubber mallet.
4. The bent edge of the outlet is pushed into the rim of the gutter, and the securing strips are fixed inside the gutter.

How to join the gutters to one another

• On the 125/90 system, the sections are butted end to end, with the joining piece, or overlapped. The gutter clamp goes over the joint, with silicone.
• On the 150/90 system, the sections overlap by 40 mm and are sealed with silicone, both between them and on the clamp that is then put on.
• The gutter end cap is pressed by hand into the edge of the gutter and tapped gently with the heel of the hand or with a rubber mallet, until it is fully in.
• The corners, inner and outer, are joined to the gutters with gutter clamps.

How to install the downpipe

1. The 60° elbow goes into the gutter outlet at the top and into the downpipe at the bottom.
2. Between two elbows goes a downpipe extension: its length is the distance between the elbows plus 100 mm, because each end goes 50 mm into the elbow.
3. The downpipe is fixed to the wall with clamps, at most 2 m apart.
4. At the bottom, the downpipe shoe is put on when the downpipe is not connected to the drain. The drain connector connects the downpipe to the drain, and the Y-branch brings two downpipes to the same shoe.

How many downpipes are needed?

One downpipe for every 10 metres of gutter. One downpipe takes the water from at most about 70 m² of roof on the 125/90 system and from about 120 m² on the 150/90 system.

125/90 or 150/90?

The 125/90 system, with a 125 mm gutter and a 90 mm downpipe, is for small and medium roofs. The 150/90 system has a 150 mm gutter and corners with gaskets and special fixings. Both have brackets made for heavy loads.

What are they cut with?

With metal shears or with a hacksaw. Cutting with an angle grinder is strictly forbidden: it burns the coating that protects the metal.

In short

A slope towards the downpipe, brackets at most 80 cm apart, the end ones 10 cm from the edge, downpipe clamps at most 2 m apart, one downpipe per 10 m of gutter. In some regions a gutter goes by other names: it is the same part. See BELPROFILE gutters and downpipes or request a quote with the length of the eaves.