Dormer extension - have you done one recently?

[MrsElsa]

We are in the "love it or list it" stage of living here. To make it suitable for DC growing up and needing separate bedrooms, would need a dormer extension to add another bedroom + ensuite. Overall size likely 2.5m x 6m. Other houses on street have had exact same extension done.
We have had the house valued and the estate agent said don't bother extending, an identical house sold recently (with the extension done) and it got 10k more than what he thinks ours could get..!!To get a significantly bigger house in this location, it would be additional 100-200k mgage. We are already in the location so if we could add the extra bedroom for well under 100k we might be able to stay here and not spend on stamp duty/fees/moving etc.... or sell this and move a few doors down to one with the extension already done...? 🙄

Would the dormer cost be coming in around 50k, 100k, more?

What would you do?

Where are you? We're in London and were quoted £100k for that sort of dormer extension (it was 20k less pre covid) about a year ago, although that was with a loft specialist our neighbours have used and who come very highly recommended by them and some other people we know, so that's probably the higher end.

We ultimately didn't have quite enough money to do it, but in our case we don't need the extra space, we just thought it might be good to do while overhauling the roof. Instead we've spent about 15% of that repairing the roof and generally repairing the outer fabric of the house.

We might yet do it if we can afford it at some point as, assuming kids may need to live with us for a while post education given the cost of London, the extra space might be useful then.

Midlands. The roof probably also needs looking at!

Are you talking about extending/increasing the size of an existing dormer, adding a new dormer to an existing room, or building a loft conversion? There's quite a difference between those different options.