extension planning

Searched a lot on the internet, but the regs don't see overly detailed in explaining the answers to my queries. I have a 1960s built 3 bed house which is on a generous corner plot, the hillside is wrapped around the house making the front a two storey home and the back more like a single storey...

I am looking at getting a second floor on extension which will be open on first floor for just path, so first floor would be a room, would planning permission be need to do this? The attached image shows how I would want it to look like, however my house is a semi and will need a bit of...

I'm hoping someone can help as I have a first draft for plans for a single rear and double side extension. The rear extension is straightforward enough but I'm struggling with ideas for the double side extension plans due to the plot shape and space between the house and angled detached garage...

Hi. Need some help on this. I live on quite a slope. My house is lower and at ground level than my neighbours. They are thinking of having an extension on the rear of their house but as they are higher than us it will not be built on ground level. If you follow me, their house has steps of...