will_k

HI, standard 18mm exterior ply, concrete screws into inner and outer leaf of cavity wall, and into conrete lintels IIRC

We have very similar wall build up & had 150mm EWI We made plywood boxes to line the rough openings & project into EWI layer about 70mm For the larger windows we screwed a block of compacfoam to the external wall to add additional support, but not sure it was neccessary.. plywood boxes themselves were very ridged once screwed & foamed in. Additional benefit of air tightness taping being really straightforward

Same response here. Getting work done by end March to be eligible is getting even less achievable with every passing week!

3 weeks and waiting, still haven't heard a peep from our application Has anyone else?

Exactly the same for us. Applied at 7:30am on the 30th, no email confirmation & no response to email. I also filled in their web "contact us" page and got a response today: " Sorry to hear that you have not received confirmation of your application to join the Green Home Grant Scheme. We are receiving an extremely high volume of applications at the moment and this has meant there may be a slight delay in a confirmation email being sent out. Please continue to check your emails (including Spam/Junk), and it should be with you in 10-12 working days. Just to let you know, from the 18th October the applicants portal will be accessible. You will be able to check or amend your personal details like your email address at this time."

We used slate tiles - external tile adhesive directly onto the EPS. Only been done a few months so can't vouch for longevity, but seems pretty robust.