Extension - To phase or not to phase...?

[gobubbles]

Our plan is to build an extension to our new house - a late Victorian terraced in the New Malden/Kingston area - but we haven't yet involved any contractor because we cannot make up our minds as to the best course of action...

Our overall budget is relatively limited (£30-40K) and there are other alterations that we'd like to see happening first. I've attached a basic plan to give you an idea of what we'd like to achieve.

Untitled

• gobubbles
• 22 Nov 2009
• 2

I've split the work into phases to minimise risks and disruption - and to manage our budget...

Phase 1
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Install a new kitchen in the old dining room.
This involves some plumbing as pipes and drain are all in the patio/side return areas. Happy for pipes to run on the wall behind the units. No need for gas point as we prefer electric cooker/oven.
--> QUESTION: do I need BR approval for the new plumbing and to convert the existing dining room suspended floor into a concrete floor (which we would like)?

Phase 2 (possibly to be combined with phase 3)
=======
Convert old kitchen into dining area and extend cloakroom as indicated in attached plan.
--> QUESTION: do I need an RSJ even if I only replace the existing windows with French doors if we don't proceed with phase 3?

Phase 3 (could be much later depending on costs)
=======
Extend into patio area. Total surface area, including cloakroom extension, is roughly 18sqm.
Daunted by potential costs here. I've read costs vary from £1500 per sqm in the Croydon area to £3000 in the Clapham/Battersea area.

--> Any idea of costs in the New Malden/Kingston area?
--> How much do you reckon it would cost for phases 2 & 3 combined?
--> Would you recommend we phase the project or do all in one go?

Advanced thanks for your help!

 

[RedHerring]

Sorry I can't give a suitable answer on the floor question but I would suspect that BR is required to ensure that you comply with DPM and insulation, etc. If you have plans drawn already for permission why not mention it as part of the overall application?

I have no idea on costs either.

The only contribution I would make is to consider making phase 3 into phase 2. I assume that a) the kitchen is a single storey and b) you have an upstairs bathroom so the shower urgency is not an issue. Therefore complete the new perimeter walls, floor, roof, openings as phase 2. It's then weather-proof and secure. With care it's easy to close off the building area from the rest of the house by removing the wall between new kitchen and new dining area after the new work is weather-proof and secure. You don't need to insert any new temporary RSJ/french windows into the existing walls. You can then complete the internal at your leisure.
That new kitchen is going to lack natural daylight though.

 

[Deluks]

What is up with the suspended floor? It it's ok then why the hassle?

It may be uninsulated under the floorboards so adding insulation between the joists may be wise, plus adding some additional supports if there is any 'bounce' . Also maintain airbricks and possibly add ventilation pipes in any new solid floor is going at the back. All very cheap jobs compared to pouring a new insulated concrete floor. If it ain't broke.........

Never mind the £1500 for Croydon, Merton Borough particularly Morden and Mitcham is 'little Poland' Polish builders galore! Like all builders though there are good and bad. (Not trying to start a debate or anything )

 

[gobubbles]

Thanks for your answers. 'Little Poland' sounds like just the sort of thing we need!

We're now thinking of combining phase 2 and 3, partly because we've found an example of costs breakdown (http://www.extensions.mitehart.com/html/extension_cost_guide.html), adapted it to our plans and found that the difference in costs is not huge whether we do the two phases together or not.

Fingers crossed, this is it now, no more changes of plans... Or is it..?

 

[Deluks]

no more changes of plans... Or is it..?

It is, I guarantee it!