Laravel Eloquent where on Join Table

I have two entities in laravel 5 Eloquent, Foo and FooType with oneToMany relation.

class Foo {

   public function fooTypes(){
    return $this->hasMany('App\FooType');
   }
}

and FooType

class FooType{

   public function foo(){
     return $this->belongsTo('App\Foo');
   }
}

question 1: how can I query using eloquent query builder and return Foos that has type_id(this column is in FooType table) of 5;

something I tried:

Foo::fooTypes()->where('type_id', 5);

and any link for good tuts about queries like this.

question two: I find out this is hard to use Eloquent query builder is it bad practice to use normal laravel queries with DB, I mean by using db I cannot use orm or something like that(or what is the benefits of using eloquent query builder):

$foos = DB::table('foos')
        ->join('fooTypes', 'foo_id', '=', 'foos.id')
        ->where('fooTypes.type_id', '=', '5')
        ->select('foos.*')
        ->get();

this type of queries are much easy and there more tutorials about it.

via Chebli Mohamed