Direct heat means cooking food right over the fire. Indirect heat means cooking it beside the fire with the lid closed, so it roasts in circulating hot air instead of being seared from below. The rule of thumb: use direct heat for food that is thin and quick, roughly 2.5 cm (1 inch) thick or less and done in under 20 minutes, such as steaks, burgers, kebabs, fish fillets and vegetables. Use indirect heat for food that is thick, bone-in or large, such as whole chickens, joints, ribs and pork shoulder. The best grilling often uses both, which is why a two-zone fire is the most useful set-up you can learn.
What direct heat does
Over direct heat, food takes the full force of the radiant heat from glowing coals or gas burners. Surfaces brown fast, fat sizzles, and you get the char and grill marks everyone loves. That speed is the whole point: a thin steak or a skewer of prawns can be well browned outside and just cooked inside in a few minutes.
The weakness is that the outside cooks far faster than the middle. On anything thick, the surface can burn before the centre is safe to eat, and dripping fat causes flare-ups that blacken food and coat it in soot.
Use direct heat for: steaks up to about 2.5 cm (1 inch) thick, burgers, chops, kebabs, chicken breast fillets, fish fillets, prawns, sliced vegetables, corn on the cob, halloumi and bread. Sausages go over direct heat too, but over a medium fire rather than a fierce one.
What indirect heat does
With the food set to one side of the fire and the lid closed, a grill behaves much like an oven. Heat reflects off the lid and circulates around the food, cooking it evenly from all sides. Browning is slower and gentler, and flare-ups are rare because fat drips somewhere other than onto the fire.
Indirect cooking covers a wide range of temperatures. At around 175–200 °C (350–400 °F) it roasts, which suits a whole chicken or a pork loin. Down at 110–135 °C (225–275 °F), with wood added for smoke, it becomes classic low-and-slow barbecue for ribs, brisket and pork shoulder, where the long cook softens tough connective tissue.
Use indirect heat for: whole chickens and turkeys, bone-in chicken pieces, steaks and chops thicker than about 4 cm (1½ inches), joints and roasts, ribs, pork shoulder, brisket, whole fish, and anything with a sugary glaze.
Which heat for which food
| Food | Heat | Grill temperature |
|---|---|---|
| Steaks up to 2.5 cm (1 in) | Direct | Hot: 230–290 °C (450–550 °F) |
| Steaks over 4 cm (1½ in) | Indirect, then direct (reverse sear) | 120–150 °C (250–300 °F), then hot |
| Burgers | Direct | Medium-hot: 200–230 °C (400–450 °F) |
| Sausages | Direct, with a cool zone for flare-ups | Medium: 175–200 °C (350–400 °F) |
| Kebabs and chicken breast fillets | Direct | Medium-hot: 200–230 °C (400–450 °F) |
| Fish fillets and prawns | Direct | Medium-hot: 200–230 °C (400–450 °F) |
| Vegetables and corn | Direct | Medium to medium-hot |
| Bone-in chicken pieces | Indirect, then direct to crisp the skin | 175–200 °C (350–400 °F) |
| Whole chicken | Indirect | 175–200 °C (350–400 °F) |
| Ribs, pork shoulder, brisket | Indirect, low | 110–135 °C (225–275 °F) |
These are rough temperatures measured at the cooking grate. Food is done when it reaches the right internal temperature, not when the clock says so.
How to set up a two-zone fire
A two-zone fire gives you a hot side for direct cooking and a cooler side for indirect cooking on the same grill. It is also your safety net: if something flares up or browns too fast, you simply move it across.
On a charcoal grill
- Light the charcoal in a chimney starter and wait until the top coals are covered in a thin layer of grey ash, usually 15 to 20 minutes.
- Tip the coals onto one side of the charcoal grate and leave the other side empty. For a hotter direct zone, pile them deeper.
- If you are cooking something fatty, put a foil tray under the empty side to catch the drips.
- Put the cooking grate back, close the lid and let it heat for about 10 minutes, then brush the grate clean.
- Turn the lid so its vent sits over the cool side. That draws heat and smoke across the food on the way out.
The vents are your temperature control. Opening them feeds the coals more air and raises the heat; closing them down lowers it. Make small adjustments and give each one about 10 minutes to take effect.
On a gas grill
Preheat with all the burners on high and the lid closed for 10 to 15 minutes. Then turn off one side (or, on a grill with three or more burners, the middle ones) and cook indirectly over the unlit section, adjusting the lit burners to hold the temperature you want.
Measure where the food is
The thermometer in a grill lid sits well above the food and can read quite differently from the temperature at the grate. An inexpensive probe thermometer clipped to the grate on the cool side tells you what the food is actually experiencing.
Using both: sear, then move (or the other way round)
Many of the best grilled dishes start in one zone and finish in the other.
- Sear, then move. Brown bone-in chicken pieces or thick pork chops over direct heat, then slide them to the cool side, close the lid and let them finish gently.
- The reverse sear. Cook thick steaks indirectly until they are about 5–8 °C (10–15 °F) below your target, then give them a minute or two per side over a very hot direct zone. You get even colour right to the edge, with the crust added at the very end.
- Glaze last. Sugary sauces burn quickly over direct heat. Cook the meat indirectly, brush on the glaze during the last 10 to 15 minutes, and give it a brief turn over the hot side if you want it sticky and caramelised.
Whichever route you take, a thermometer tells you when to stop. Our guide to meat temperatures for grilling has the safe minimums and a steak doneness chart.
Common mistakes
- Cooking everything over direct heat. The classic result is chicken that is black outside and undercooked at the bone.
- Leaving the lid open for indirect cooking. Without the lid there is no oven effect, and food on the cool side barely cooks.
- Spreading the coals evenly across the grill. It leaves you nowhere to go when fat flares.
- Putting food on a cold grate. It sticks and tears. Preheat for 10 minutes and brush the grate clean.
- Constantly moving and pressing food. Leave it long enough to brown, and never squash burgers with a spatula, which pushes out juice and fat.
- Saucing too soon. Sugar burns long before thick meat is cooked through.
Putting it into practice
For most people the fire, rather than the recipe, is the hard part, and it is where BBQ Grill Secrets begins: how to build a two-zone bed, when to close the vents and how long each cut really needs. For direct heat, try the Lamb Kofta Kebabs or Mexican Grilled Street Corn (Elote). To practise with both zones, the Spatchcock Grilled Chicken and the Reverse-Seared Ribeye are ideal. When you are ready to go properly low and slow, our piece on what happens to meat in a smoker is the natural next step.
Questions people ask
Should the grill lid be open or closed?
For indirect cooking, always closed: the lid is what turns the grill into an oven. For thin food over direct heat it matters less, but closing the lid helps thicker items such as chops and burgers cook through evenly, and it calms flare-ups by limiting the air reaching the fire.
How hot is "medium" on a charcoal grill?
Roughly 175–200 °C (350–400 °F) at the grate, with medium-hot up to about 230 °C (450 °F) and hot above that. A grate-level thermometer is the most reliable guide. The traditional hand test, holding your palm above the grate and counting how long you can bear it, is a rough check at best.
Can I cook indirectly on a small kettle or portable grill?
Yes. Bank all the coals against one side and cook on the other, with the lid on. On very small grills the cool zone is narrow, so choose smaller joints, or spatchcock a chicken so it lies flat and cooks evenly.
Is indirect grilling the same as smoking?
Smoking is a form of indirect cooking done at low temperatures, usually 110–135 °C (225–275 °F), with wood added for smoke. All smoking is indirect, but not all indirect cooking is smoking.