Heat the grill to 400°F, 200°C, or gas mark 6 if your grill has a thermometer on the lid.
Pat dry the chicken removing any parts that might be in cavity. Generously season the entire outside of the chicken.
Place on indirect heat on the grill and cover. Rotate the chicken so the side facing the heat is turned away at 50 minute mark. Cook for about an hour and 40 minutes or until the internal temperature reaches 165°F or 74°C. About 10 minutes before the chicken is ready brush the barbecue all over the chicken.
Once the chicken has been removed from the grill brush another layer of barbecue sauce on the chicken. Slice and serve.