Rumbutza

Hey, so I live on a farm and we have a few sheds/barns either in disuse or in desperate need of repair/knocking down. We already complete 1 conversion of an old timber frame barn to a house for one family member with my brother and I doing 95% of the labour. Now I'm trying to determine which is most suitable to apply for permission to build my home. My problem is there is a small sized portal shed 17x8 meters, it's only 3.4m height at the peak of the roof, so bungalow. What I'm struggling with is how to complete the exterior walls. Is there a way to bridge between the steel uprights with timber studs? I can't find any information on if this is feasible e or how to do it? I understand I need some form of cold bridging. Could I pack the stud off the steel and use a vapour barrior? It will be permitted development, so I can't exceed the original dimensions. I'm not allowed to build an external stud arou d the perimeter to avoid the cold bridge etc. I know it can be done with metal slip ins etc, but I'm much more comfortable working with timber. Since costs need to be kept minimal we want to do as much of the work as possible and that's not an option with steel I fear Thanks in advance for any advice