Braai Flue Installation: A Practical Guide for South African Homes

1. Size the flue to the firebox

The rule is simple: the flue diameter must match or exceed the manufacturer's spec. For most residential built-in braais that's a 200 mm insulated flue. Undersizing to 150 mm to save cost is the single most common cause of smoke pouring back into the entertainment area — and it can't be fixed later without ripping out the ceiling.

2. Insulated vs single-skin

• Single-skin flue: only for the section inside the firebox itself.
• Insulated (twin-wall) flue: mandatory the moment the flue passes through a ceiling, roof, or any combustible material.
• Insulated flue keeps outer temperatures safe (60–80 °C) and improves draw by keeping flue gases hot.

3. Roof penetration and clearances

The flue must clear the highest point of the roof within 3 m by at least 600 mm — this is the SANS 10400-V clearance rule and it exists for wind reasons, not aesthetics. In Cape Town's southeaster, a flue that ends below the ridgeline will down-draught every gust.

Use a proper storm collar and roof flashing rated for the roof type (IBR, tile, slate). Silicone alone is not a flashing.

4. Cowl choice matters in the Cape

A fixed cowl is cheap and fine for inland installs. Anywhere the wind swirls — Atlantic Seaboard, Southern Suburbs, West Coast — fit a rotating (H-cowl or spinning) anti-downdraught cowl. It's the difference between a braai you use every weekend and one you fight with.

5. Common installation mistakes

• More than two 45° bends in the flue run (each bend costs ~10% draw).
• Horizontal runs longer than 500 mm.
• Flue terminating inside a covered patio ceiling instead of above the roof.
• No access point for cleaning — flues need sweeping annually.

Get it installed correctly

We supply and install flue kits sized to your firebox with a site inspection first. Retro-fixing a bad flue costs 3–4× more than getting it right on day one.