Loft conversion with valley roof: can you convert only the rear section?

[Otter1986]

This is very niche BUT...

We are looking at a house with an unusual roof shape; basically it's cut into two parts. I believe this is called a valley roof. It technically gives us two small lofts, that are separated by a gutter area that has a sky light in currently. I haven't a picture of it - there isn't one available - but that is how the EA described it and makes sense when we consider that the stairs are in the middle of the house not up the side like a typical terrace.

We could - at great expense - build a brand new piece of roof to fill in the gap and create a big dormer room. But actually we don't really need that - we just need a little office cubby really. So instead, we are wondering if we can just convert the back bit and essentially have a back loft conversion only. Is that possible - has anyone done it? I've googled this and haven't really gotten much by way of answer - though I assume anything is possible really.

I've contacted some builders but haven't heard back. We're under pressure to offer so I was hoping someone else may have done something similar?

Thanks

You dont say whether the valley runs front to back or side to side. If you’re not sure look at Google satellite amd post a snip here?

If it’s a Georgian/early Victorian terrace the valley may go front to back. You can strip off the whole roof and put in a loft extension. Often a nice arrangement is to have a small terrace at the front to space the loft from the front parapet and hide the new roof from the street. If that’s like your house I can maybe find a similar example of the planning portal that I know of - once one got permission lots of the street did the same

If it is side to side you could put up beams below each ridge and then have a flat roof between. But usually the problem with the double roof is that there is half the headroom of a usual single pitch. So you may not have sufficient head height to get anything much there…

We have a huge normal roof and are struggling with stairs due to the roof height needed over the stairs without adding a dormer. So just keep that in mind. It's a bit hard without a picture.

The houses on our street are like this. Most people have just done the rear outrigger section (over the kitchen and back bedroom/bathroom, which is a 'normal' roof) which does a small double bedroom and a small shower room. It's permitted development and reasonably cost effective. I think that's the same as you are thinking.

We're going for broke though and doing the front to back mansard if we get planning. It's basically building an extra storey on the house.

Do you mean like this??
If you go on google earth you can probably screenshot a pic to be clearer.

This is ours. The sticky out bit in the middle is the stairs. We have a roof above kitchen and then above the back room/old dairy. What we want to do is have that whole back bit as one loft with a Dutch barn style roof