What are my rights even if my renting lease has expired?

[marcom]

I have been renting a flat from my landlord for 5 years. During these 5 years I have been taking care of the flat and have paid rent and bills always on time. I m now building my own apartment, which however does not have a precise completion date. As an architect, I can say it will be a shell in the next 2 month. Here is the problem. I have told my landlord at least a year ago that I would move out into my new apartment and would like to have a smooth transition between the 2. I have also offered to keep a room there (for my girlfriend) or to manage the future tenants while me moving out. My lease has officially expired on August the 24th this year. In the meantime my landlord has found another person ready to sign a new lease for 2 years. He disregarded what I suggested to him as an option and asked me to tell the builders to speed up with the work on my flat. In response, I had told him that I could not give him a precise date, but approximately it would have been end of October. In the meantime the new tenant has moved in and is already complaining about me staying in the flat. The work has slow down and it looks like the shell of my flat will be ready by end of November. I had warned all parties of possible delays and I m now under pressure to justify this. I would like to avoid moving to a temporary accomodation as this would affect both my work (I work from home) and my flat. The landlord asked me to negotiate with the new tenant (he moved to New York), which I tried, resulting in just non fruitful arguments. Could you advise me on the possible scenarios here. Please not the landlord is quite a close acquaintance of mine and I would not intend to create problems for him, nor for the new tenant, but I feel somehow not respected at this stage.

[boxtops]

Are you in the US (you mention New York)? This is a UK site, the rules may be different here.

[bednobs]

if you are in the uk, then i'm not surprised the new tennant is annoyed with you - you don't have a contract to rent the place yet are still living there, you should ahve moved out when your contract expired, or signed a new contract.
Frankly, you are taking the Fosters staying there with no contract!

[bushbaby_de]

bednobs - if neither the landlord or tenant serve notice on the other, the tenancy moves over to a periodic tenancy - it doesn't just cease!