How To Install Aluminium Downpipes

Installing aluminium downpipes is a straightforward process when following the correct steps. These high-quality downpipes - whether swaged or flush-joint - are lightweight, easy to handle, and deliver excellent long-term performance when securely fixed.

This step-by-step guide covers ARP Colonnade round, square, and rectangular swaged and flush joint aluminium downpipes, ensuring a professional and leak-free installation.

Materials Needed for Installation

Before starting, gather the following tools and materials:

• Spirit level or straight edge
• Sealant caulking gun (low-modulus sealant, e.g., Arbosil 1096)
• Hacksaw, electric jigsaw, or chop saw (for cutting pipes)
• Tape measure
• Pencil or chalk
• String line or laser level
• Screwdriver and suitable attachments
• Small wrench
• Stainless steel screws and plastic wall plugs (for secure fixing)

General Preparation

1. Inspect the Fixing Surface:
   Check that the wall, fascia, or fixing background is structurally sound and capable of supporting the downpipe load.
   
   
2. Plan Layout
• Align the downpipe outlet with the gutter outlet or hopper head to ensure smooth rainwater flow.
• Plan any required offsets, branches, or bends to effectively route the downpipe to the drain or gully.
  
  
3. Cutting the Downpipe:
• Use a hacksaw or electric jigsaw to cut downpipe sections to the required length.
• Avoid angle grinders as they can damage the pipe coating.

De-burr cut edges and apply touch-up paint to powder-coated pipes to prevent corrosion.

Step-by-Step Installation Guide

Step 1: Start from the Outlet

• Begin installation at the gutter outlet or hopper head.
• Attach any necessary offsets or bends to match the wall projection and secure them in place.
• Apply low-modulus sealant inside the socket (for swaged or flush-jointed pipes) to create a watertight connection.

Step 2: Secure the First Downpipe Section

• Fix the first downpipe section to the outlet using the appropriate connection type:
• Swaged Joints: The spigot end of the pipe fits neatly into the socket end of the section below. Apply sealant to the inside of the socket before fitting.
• Flush-Jointed Pipes: Apply sealant to both the socket and the inside of the supporting pipe clip for added stability.
• Secure a pipe clip directly beneath the socket to support the weight of the downpipe.
• Use stainless steel screws and plastic wall plugs to ensure a firm, rust-resistant fix.

Step 3: Add Additional Downpipe Sections

• Fit each additional section by inserting the spigot end into the socket, applying sealant as required for a watertight seal.
• Secure each section with a pipe clip positioned directly beneath the socket.
• Install additional clips at 2-metre intervals to provide support and prevent sagging.

Step 4: Terminate the Pipe into the Drain or Gully

• Use a shoe, drain adaptor, or offset to guide the water flow into the gully or drainage point.
• If no shoe is installed, ensure an access pipe is fitted to allow rodding access, as per local building regulations.

Top Tips for Success

• Ensure Vertical Alignment: Use a string line or laser level to keep the downpipe perfectly vertical for a clean finish.
• Seal Properly: Use low-modulus sealant (Arbosil 1096) for all swaged or flush joints to prevent leaks. Avoid applying sealant in wet weather or temperatures below 5°C or above 50°C.

Fix Securely: Use stainless steel screws to prevent corrosion and ensure compatibility with the aluminium material.

Why Proper Installation Matters

Correctly installed round aluminium downpipes ensure:

• Efficient rainwater drainage without leaks or sagging.
• Long-lasting durability, thanks to secure fixing and watertight joints.
• A polished, professional finish that complements your aluminium guttering system.

For further assistance or to download the complete installation guide, visit our Technical Guides page or contact the Aluminium Superstore team on 01296 674099 for expert advice.