carljarrett

External insulation will be the standard polystyrene type i guess to render onto

Hi all. I have built a timber framed second floor and gable to gable roof with a roof room on top of my bungalow. I have already has to overhang the timber sole plates and put a larger cavity on the new walls just to get enough overhang to account for 50 mm external insulation downstairs, This is why i want to insulate internally in the bungalow aswell as 50 mm externally. I will be battening the inside walls and then putting the phenolic on top across the battens, so there will be a void behind them to breath. Is this ok ?

Hiya not sure if this is still open or relevant, however I have taken on a bungalow to house renovation myself. I am an engineer by trade never done building work and I am currently battening the outside ready for render boards. I put timber frame in stick form straight on top of the bungalow walls and then trusses on top to give us a 11.2 m long by 4.2 m wide, 2.4 m high room in the loft. It’s more than doable. I’m quite the celeb on my main road now lol. I’ve done it all on my own other than standing the trusses up where I had my fiancées grandad help as they were fooking huge ! the hardest bit was working out the connection between the old and new, I chemical fixed studding deep into the bungalow brick walls and fixed the timber sole plate down via the studs plus wall restraints etc as per normal standards. I’m self taught from YouTube mainly I would say the tricky bit is the render transition from timber to original bungalow brick, especially as we are insulting externally on the downstairs so I had to build the timber frame above with an adequate overhang so it finishes somewhat flush with the downstairs EWI. my bungalow is a wonky rectangle, so I had to build a nice true new structure on a wonky substructure. Which will need to be made up and hidden within the battening and render board. I basically have 4 steels running across the bungalow which meant I was free to knock all internal walls down if I desired so gave us huge scope to redesign. There as no point starting a new with our build as the size and shape already made best use of the plot. it’s all going on YouTube too

Hi all, I have not been able to find this answer anywhere… can you do both internal and external insulation on solid brick walls. My plan is 75 mm external insulation and then silicone render but also batten and insulate internally with kingspan 25 m phenolic insulation on battens off the wall.. Will this cause condensation/damp/ventilation issues? thank you