Why Choosing the Right Outdoor Ethernet Cable Matters

Running ethernet cable outside presents unique challenges that standard indoor cables simply can't handle. Exposure to moisture, UV radiation, temperature fluctuations, and physical damage can quickly degrade performance or cause complete failure. Whether you're connecting a garden office, security cameras, or extending your network to an outbuilding, selecting the proper outdoor-rated ethernet cable is crucial for reliable, long-term connectivity.

This guide will help you navigate the key considerations and find the best ethernet cable to run outside for your specific requirements, ensuring your outdoor network installation delivers consistent performance for years to come.

Factors to Consider When Choosing Outdoor Ethernet Cable

Cable Category and Performance

For outdoor installations, CAT7 cables offer excellent future-proofing with support for 10 Gigabit speeds up to 100 metres. The superior shielding in CAT7 cables also provides better protection against electromagnetic interference, which is particularly valuable in outdoor environments where cables may run near power lines or other sources of interference.

Weatherproofing and Protection

Outdoor ethernet cables must withstand harsh environmental conditions. Look for cables with:

• UV-resistant outer jackets to prevent degradation from sunlight exposure
• Waterproof construction with gel-filled cores or water-blocking compounds
• Temperature tolerance typically ranging from -40°C to +75°C
• Rodent-resistant materials to prevent damage from wildlife

Installation Method

Consider how you'll be running the cable:

• Direct burial cables can be buried underground without additional conduit
• Aerial installation requires cables with messenger wire or additional support
• Conduit installation allows use of standard outdoor-rated cables with protective ducting

Distance Requirements

Ethernet cables maintain full performance up to 100 metres. For longer runs, consider the total distance including any indoor routing to ensure you stay within specifications.

Top Picks for Outdoor Ethernet Cables

Which Cable for Which Application?

Direct Burial CAT7 with Gel is ideal for:

• Underground runs to garden offices or outbuildings
• Permanent installations where digging trenches is feasible
• Areas with high moisture exposure
• Installations where conduit isn't practical or desired

Shielded CAT7 S/FTP works best for:

• Aerial installations with proper support
• Runs through outdoor conduit or trunking
• Areas with high electromagnetic interference
• Temporary or semi-permanent installations

Comparison Table

Product	Price	Length	Cost per Metre	Direct Burial	Shielding	Best For
Direct Burial CAT7 Gel	£261.84	305m	£0.86	Yes	S/FTP	Underground runs
Shielded CAT7 S/FTP	£239.06	305m	£0.78	No	S/FTP	Aerial/conduit

Installation Tips for Outdoor Ethernet Cables

Planning Your Route

Before installation, carefully plan your cable route to minimise exposure to potential damage. Avoid areas where digging might occur in future, and maintain safe distances from electrical cables (minimum 30cm separation).

Direct Burial Installation

• Use a spade to create clean, straight trenches
• Lay cables on a bed of sand or fine soil
• Avoid sharp bends - maintain a minimum bend radius of 4 times the cable diameter
• Install marker posts at both ends and any direction changes

Aerial Installation

For above-ground runs, proper support is essential:

• Use galvanised steel messenger wire for spans over 10 metres
• Install support clamps every 1-2 metres
• Allow for thermal expansion with service loops
• Ensure adequate clearance from power lines (minimum 3 metres)

Entry Points and Sealing

Where cables enter buildings, proper sealing prevents water ingress:

• Drill entry holes with a slight downward angle
• Use weatherproof cable glands or grommets
• Apply external-grade sealant around entry points
• Create a drip loop before the entry point

Common Mistakes to Avoid

Inadequate Protection

Don't assume that running cable through basic plastic conduit provides adequate protection. Outdoor conduit must be UV-stabilised and properly sealed at joints.

Insufficient Burial Depth

Shallow burial (less than 30cm) leaves cables vulnerable to damage from garden tools, frost heave, and root growth. Always follow minimum depth guidelines.

Poor Cable Management

Avoid tight bends, kinks, or crushing the cable during installation. These can cause immediate performance issues or create weak points that fail over time.

Mixing Cable Types

Don't splice indoor and outdoor cables together. The connection point becomes a failure point, and you lose the weatherproofing benefits of the outdoor cable.

Ignoring Future Access

Plan for future maintenance or modifications. Document cable routes and consider installing spare capacity or pull-through conduit for future needs.