Now, Angular 4 has email validator built-in https://github.com/angular/angular/blob/master/CHANGELOG.md#features-6 https://github.com/angular/angular/pull/13709
Just add email to the tag. For example
<form #f="ngForm">
<input type="email" ngModel name="email" required email>
<button [disabled]="!f.valid">Submit</button>
<p>Form State: {{f.valid?'VALID':'INVALID'}}</p>
</form>