Huddersfield is built of Pennine stone. Terraces in Lockwood, Moldgreen, Paddock, Marsh and Lindley wear stone-slate roofs, often on the original heavy timbers, and the installation team looks at those before agreeing a panel count. Victorian villas in Edgerton (a conservation area) and Gledholt have large, complicated roofs with several pitches. That usually gives you a decent south-facing slope somewhere, even when the front door faces north.
Beyond the town, Slaithwaite, Marsden, Honley and Holmfirth climb the steep sides of the Colne and Holme valleys. A stone terrace on the sunny side can beat a flat suburban semi, because nothing shades it. A north-facing roof on the dark side may never pay, and you will hear that at the survey instead of getting a quote. The flattest, simplest roofs round here are on the 1960s to 1990s private estates at Almondbury, Kirkheaton, Fenay Bridge and Lepton.
North Kirklees is another story. Dewsbury, Batley, Mirfield and Heckmondwike have red-brick terraces alongside the stone ones, big inter-war estates and a steady supply of new-build on old mill sites. Think of them as Wakefield-style roofs: plainer pitches, concrete tiles, modern wiring and a one-day fit.