We live between 2 rented houses with very different landlords. We're planning a single storey extension, and had spoken to both sides landlords informally to let them know before we applied for planning permission. Both were fine. We're at number 7, and share a ground floor outdoor passage with number 5, which leads to the gates to both gardens. The first floors are joined - it's a flying freehold. Planning permission came through, and we sent out party wall notices at end of March. Number 9 responded positively immediately, but 5 didn't. I emailed him to remind him that the bank holiday might hold things up, and suggested he get in touch for a chat if he had any concerns, before the expiry. We then went away for 4 days, and I didn't get an email reply, so assumed he'd posted the agreement. He hadn't. We don't have his phone number, only his email and home address, which is local. So DH popped round to speak to him, only to be told by his wife that he's away, and not due back for another 4 weeks. She said she'd contact him. DH went back today and his wife has said that he will contact DH by WhatsApp, but would like a copy of the full plans before he decides.
Obviously, the deadline has now passed, so my understanding is that legally we're considered in dispute. But as he didn't receive the original notice (it's unopened in his house), I'm assuming that we don't need to leap in and appoint a party wall surveyor? We're trying to get agreement in writing, and hope that will hold up legally. As he has an extension almost identical to the one we're proposing, I can't see that he'd win any dispute anyway.
Sorry for long post. Disclaimer that I will not be relying on legal advice obtained via mumsnet forum, but does anyone have any thoughts/advice?