Modernisation and extension

[wannabeamummysobad]

Mumsnetters, I am hopeful to exchange on a property next week. The current owners have lived there for >50 years and it requires modernisation throughout plus we want to extend.

I've attached the current floor plan. Below is what we are wanting to do;

• knock through kitchen reception (red) to create an open U shaped kitchen with separate family space/Play area

-part reconfigure the garage to create a utility room (purple)

• loft extension (master bedroom with en suite)

Any thoughts on what I can expect to pay?
Or if you had this space what would you do?

Ps- my husband is adamant we have a separate dining room so we won't be knocking through to the other reception (green)

Pps- the property is in Greater London

Thanks for any advice

If you just knocking down walls then you might need some steels but no foundations etc that will be cheaper. I reckon £150k depending on how fancy you want your finishes….you could do it for less with a b&q kitchen and bathroom.

Very nice floorplan, the house will have a great flow when all the work is completed.

The knock through will most likely require steels, so all in for labour and materials for the knockthrough element only (including the cost of structural engineer), you are probably looking at about 5k - 10k (includes the cost of making good). You will most likely need to reconsider where the current windows/patio doors are in the new open place, and may be a good idea to have sliders or bifolds added. This could be about 5k - 10k. Depending on what type of electrics/plumbing is on the wall that is being knocked down, you may need to consider the cost of altering electrics/plumbing. Budget about £2k for that.

Finally, you would need new kitchen, flooring, decorating, lighting etc added on top. For mid range finish, budget about £20k all in. So in total, to create your mid range kitchen/open plan space, i'd budget £40k all in (labour, fees and materials).

Reconfiguring of the garage to create a utility should be easy as there is plumbing nearby already. I'd budget £5k.

Loft conversion, if dormer with ensuite, i'd budget £75k all in (for mid range spec) as your floorspace seems quite large.

So for the specific works you listed above, I'd budget £120k. If you are also renovating the remainder of the house, I'd budget just under £1k per sqm for a mid/high range finish. So let's add another £80k on top based on your floorplan.

I think £200k all in seems about right for that size house in London.

Thank you @BadAtMaths2 @novicebynature . Glad to know we are in the correct ballpark. We'll be getting a design team in so fingers crossed they think the same.

Our house has a similar floor plan, we knocked through between the two reception rooms to make one big one dual aspect room. Really glad we did!

@resuwen how long ago did you do this? Where are you based? Do you remember the cost per sqft or sqm?
Cheeky but do you have any photos?

I've got a few calls lined up early next week. Fingers crossed builders are available at a reasonable price