Am heading to Builth Wells tomorrow from Birmingham(Aston) looking at the map the best way seems to be out to Kidderminster on the 456 then pick up the 4112 heading to Brecon then turn north onto the 4470 will be weighing about 30 ton am open to any suggestions if there is a better way. Thanks in advance 
How about Kidderminster,Leominster,Kington onto the A44 then you can turn left for Builth.
Sorry cant remember the road numbers but we come that way loaded from Builth.
Pursy
I’d go with Pursy’s suggestion. A456 from Kiddy to Tenbury is a bit of a switchback but there’s no real option.
Follow Pursy’s route A456-A49-A44 past Kington until the Forest Inn, then the A481 through to Llanelwedd which is next to Builth Wells.
Alternative route is follow the A4112 after Leominster signed Brecon picking up the A438 until Three â– â– â– â– â– and then take the signs for the A470 takes you right into Builth Wells.
Watch for the Camera vans.
Don’t turn left into tenbury either, carry on past to wofferton/ a49.