Vented Dryer Installation: What You Need to Know

Vented dryers remain popular in Australia thanks to their affordable price and fast drying times. However, unlike condenser or heat pump models that can be placed almost anywhere with a power outlet, vented dryers require proper exhaust installation to function safely and efficiently. This guide covers everything you need to know about installing a vented dryer correctly.

Improper venting is one of the leading causes of dryer fires and poor dryer performance. Taking the time to understand and implement proper ventilation isn't just about compliance—it's essential for safety and getting the most from your appliance.

Understanding Vented Dryer Requirements

Vented dryers work by heating air and passing it through tumbling clothes to absorb moisture. This hot, humid air must be expelled from your home. Unlike condenser dryers that condense moisture internally, vented dryers require an external exhaust pathway.

What Happens Without Proper Venting?

• Moisture damage: Humid air releases into your home, promoting mould growth and damaging building materials
• Poor performance: Without proper airflow, drying times increase dramatically
• Fire risk: Lint accumulates in inadequate venting, creating significant fire hazards
• Overheating: Restricted airflow causes the dryer to overheat, potentially damaging components or triggering safety shutoffs

Exhaust Duct Materials

The material you use for exhaust ducting significantly impacts safety and performance. Not all materials are appropriate for dryer venting.

Rigid Metal Duct (Best Choice)

Rigid aluminium or galvanised steel duct is the gold standard for dryer venting. It provides:

• Smooth interior that minimises lint accumulation
• Maximum airflow with minimal resistance
• No sag points where lint can collect
• Fire resistance—won't melt if dryer overheats

Semi-Rigid Metal Duct (Acceptable)

Semi-rigid aluminium duct is more flexible than rigid duct, making installation easier in tight spaces. While it has more surface texture where lint can catch, it's still a safe option when installed correctly and maintained regularly.

Flexible Foil Duct (Avoid If Possible)

Thin foil ducting is inexpensive and easy to install but has significant drawbacks:

• Ribbed interior traps lint
• Easily crushed, restricting airflow
• Sags over time, creating low points
• Can tear, allowing lint to accumulate in walls

If you must use flexible duct, use the shortest possible length and support it to prevent sagging.

Plastic/Vinyl Duct (Never Use)

Plastic or vinyl exhaust hoses are fire hazards and should never be used. They can melt if the dryer overheats, potentially causing fires. Most Australian building codes prohibit their use for dryer venting.

Exhaust Run Guidelines

Keep It Short

The shorter your exhaust run, the better. Maximum recommended lengths vary by dryer, but general guidelines suggest:

• Ideal: Under 3 metres total length
• Acceptable: 3-6 metres
• Long runs may require booster fans

Minimise Bends

Every bend in the duct reduces airflow. Each 90-degree elbow is equivalent to adding approximately 1.5 metres of straight duct. For optimal performance:

• Use 45-degree elbows instead of 90-degree where possible
• Avoid more than two 90-degree turns total
• Use smooth, gradual bends rather than tight corners

Maintain Proper Slope

If your exhaust run isn't perfectly horizontal, slope the duct downward toward the exterior vent. This prevents condensation from pooling inside the duct and allows any moisture to drain outside.

External Vent Requirements

Vent Cap Selection

The external vent cap where exhaust exits your home should include:

• Damper/flap: Opens when dryer runs, closes to prevent backdrafts
• Pest screen: Prevents birds and rodents from entering (use wide mesh that doesn't trap lint)
• Weather protection: Hood design that prevents rain entry

Placement Considerations

• Position away from windows and doors to prevent humid air re-entering
• Avoid placement near air conditioning intakes
• Keep clear of vegetation that could block airflow
• Ensure accessibility for regular cleaning and inspection

Through-Wall Installation

Installing a wall vent typically requires cutting through external cladding and the wall cavity. For brick or masonry walls, a core drill creates a clean circular opening. For weatherboard or metal cladding, careful cutting and proper flashing is essential to prevent water ingress.

Step-by-Step Installation Process

1. Plan Your Route

Before purchasing materials, map out the exhaust path from dryer to exterior. Identify the shortest route with fewest bends. Check for obstacles like pipes, wiring, or structural members in the wall cavity.

2. Gather Materials

• Appropriate duct (rigid metal preferred)
• Duct clamps or foil tape (not standard duct tape)
• External vent cap with damper
• Wall thimble (for through-wall section)
• Sealant for weatherproofing

3. Install the External Vent

Start from outside: cut the wall opening, install the vent cap, and seal thoroughly around the edges to prevent water infiltration.

4. Run the Ductwork

Connect duct sections from the wall vent back toward the dryer location. Secure each joint with clamps or approved foil tape. Support the duct to prevent sagging.

5. Connect to the Dryer

Attach the duct to the dryer's exhaust outlet. Most dryers use a simple clamp connection. Ensure the connection is secure but not so tight that you can't disconnect for maintenance.

6. Test the System

Run the dryer on air-only (no heat) and check:

• External vent flap opens during operation
• Strong airflow exits the vent
• No air leaks from duct joints
• No unusual sounds indicating obstructions

Alternative Venting Options

Window Venting

If wall installation isn't possible, venting through a window is an alternative. Window venting kits include a panel that fits in a partially opened window with a duct connector. However, this has drawbacks:

• Less secure than permanent installation
• Window can't be fully closed during operation
• May not seal well, allowing insects and weather in
• Not suitable for upper floors in high-rise buildings

Roof Venting

In some homes, routing exhaust through the roof is the most practical option. This requires:

• Appropriate roof penetration and flashing
• Vent cap designed for roof installation
• Vertical rise consideration (hot air rises, which can help airflow)
• Professional installation recommended due to waterproofing complexity

Maintenance Requirements

Proper installation is just the beginning. Ongoing maintenance keeps your vented dryer safe and efficient.

Regular Checks

• Monthly: Check external vent flap moves freely
• Quarterly: Inspect accessible duct sections for damage or disconnection
• Annually: Have the full exhaust system professionally cleaned

Signs of Problems

• Longer drying times than usual
• Dryer feels excessively hot
• Laundry room becomes humid during drying
• Visible lint around external vent
• Musty smell on dried clothes

When to Choose a Ventless Dryer Instead

While vented dryers offer lower purchase prices and faster drying, proper venting isn't always practical. Consider a condenser or heat pump dryer if:

• You're renting and can't modify the property
• External wall access is difficult or impossible
• You live in an apartment with strata restrictions
• Your laundry is far from exterior walls
• You plan to move and want a portable solution

The upfront cost of ventless dryers has decreased significantly, and heat pump models offer substantial energy savings that can offset the price difference over time.