This work aims at proposing a new procedure for parametric problems whose separated representation has been considered difficult, o r w hose S VD c ompression i mpacted t he r esults i n t erms o f p erformance a nd a ccuracy. T he p roposed technique achieves a fully separated representation for layered domains with interfaces exhibiting waviness or-more generally-deviating from planar surfaces, parallel to the coordinate plane. This will make possible a simple separated representation, equivalent to others, already analyzed in some of our former works. To prove the potentialities of the proposed approach, two benchmarks will be addressed, one of them involving an efficient s pace-time s eparated r epresentation a chieved b y c onsidering t he same rationale.