How to avoid seepage in future during construction

I want to know that what is the method to avoid seepage of walls and roof in future if we are making a new house

For Roof please ask mistri ka lohay ka garmala maray sath sath jab lantar dal raha ho.

Thanks & Regards,

Zayad Mohsin

MASC(Deals in Construction, Building materials & Real Estate)

Mohsin & Sons Construction.

Phone : +92-51-4918376

Website : www.masc.com.pk