app.route.ts

export const appRoutes: Routes =[
  {
    path: '',
    redirectTo: '/home',
    pathMatch: 'full'
  },

  {
    path: 'home',
    component: HomeComponent
  },

  { path: 'costing', loadChildren: 'app/costing/costing.module#CostingModule' },

  { path: 'admin', loadChildren: 'app/admin/admin.module#AdminModule' },

];

export const appRoutingProviders: any[] = [
  authProviders,
];

export const routing: ModuleWithProviders = RouterModule.forRoot(appRoutes);

cost.route.ts

const routes: Routes = [

  {
    path: '', component: CostingComponent,
    children: [

     { path: '', component: EmptyComponent, pathMatch: 'full' },
     { path: 'payments', loadChildren: 'app/costing/payments/payments.module#PaymentsModule' },
     { path: 'variations', loadChildren: 'app/costing/variations/variations.module#VaritionsModule' }
    ]
  }
];

export const costingRouting: ModuleWithProviders = RouterModule.forChild(routes);

payment.route.ts

const paymentsRoutes: Routes = [

  {
    path: '',
    component: PaymentsListComponent},
  {
    path: 'detail:id',
    component: PaymentsDetailComponent 
  },

];

export const paymentsRouting: ModuleWithProviders = RouterModule.forChild(paymentsRoutes);