CharlotteJ

I dont believe it is class Q. It was an agricultural building although a modern building rather than stone barn. We have full PP for change of use to two dwellings - its a large C shaped building so a two bed and a 7 bed separated by an internal fire wall. Thanks, I will have a search on youtube.

Hi, we are converting a concrete block building that was originally built around 2007. It has 7n concrete blocks (100mm thick) external walls apart from gable ends and the long rear wall which are all 7n concrete blocks on the flat side (215mm) thick. There is a DPC strip under all the blocks at floor level. We have established that we need to build the floor up in order to insulate and achieve required U values. We are now looking at the walls and I want to check cavity requirements. I have seen conversion videos where there is no cavity and studwork is covered with a membrane and installed up against the block walls then insulated. - Not sure how to calculate the U value of this method. The Kingspan U value calculator option is 50mm cavity, studwork backed with OSB and membrane, insulation inside studs, then insulated plasterboard - to achieve required U values. This is difficult to retrofit as I think it would need tying in? Also would we need a cavity tray? - we could achieve this as there is enough DPC protruding from the bottom of the walls to wrap across the 100mm high sole plate, to create the slope and install weepholes. Two very different methods - any advice much appreciated! Thanks

Thanks everyone. Would stud wall with insulation, ply both sides (this makes it structural according to BC) then boarded each side be suitable? - I could then find out the stud wall thickness and what insulation and plasterboard to use in order to meet the soundproofing requirements.

Thanks so much for all your advice. On talking with BC today, the firewall also needs to be 'structural' although not load bearing (single level building). So a 100mm solid concrete block wall is suggested as being appropriate for fire rating - 60 mins required - I need to check if it will give adequate sound insulation but would appreciate your advice and any opinions on this.

Thank you, I will check out the guides that you mentioned.

Hi, we are converting a large building into 2 dwellings - we need an internal firewall to separate them. From various builders advice and the internet, we are thinking a stud wall using 6"x 2" timber, filled with either rockwool or rigid celatex type insulation and boarded both sides with pink plasterboard, then skimmed. This will continue up into the roof space. This will all be approved by our very helpful building inspector before installation, but I would like to have something to show her. Any comments, advice or additional information is very welcome. Thank you.

Yes it was previously an agricultural building so exempt. Thanks for your help.

Thank you. That's really good to know

Joe90 - I was hoping he would advise what he required. I will arrange for him to come out for a site visit. Thanks so much for your reply.

Hi, we are undertaking a conversion of an agricultural building on our land. It was built to a high standard in 2007 and is concrete block/tiled roof with foundations and concrete floor. How do we go about getting the foundations, damp proof course, oversite concrete signed off, when they are existing and therefore cannot be inspected beforehand. Same with the roof trusses (single storey) - all timber is exposed but is it enough to call them out to look at them and them say 'yes' or do I need paperwork with calculations etc to show them. I have tried google for answers and asked our building control officer but he cannot advise and said to contact a builder. We are trying to keep the costs down as ecology surveys for planning were through the roof as a possibility of bats. Any advice would be really appreciated. Many thanks