How much would this extension cost in South West London?

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newhomebuild said:

HHarry said:

I spent £75k 15 years ago in North Hampshire and did most of the internals myself.

I reckon mclaren is right at £150k+

Gosh! Wonder how people finance this as first time buyers

Buying a three bed house in fringe London and then adding another bedroom and a reception room isn't a realistic first time buy for most. 

Agree that £150k is a sensible cos - that does include everything: decoration, a sensible kitchen, the remaining fees etc. but it's a budget you'd still need to be careful and make a few sacrifices to remain within. 

Why has the current owner gone to the £k's of trouble to get planning and not followed through? Is there some issue that has stopped them?

To take a project like this on you should at least have access to some contingency money over the 150k, say a further 30k. You don't want to get stuck half way if there is some unexpected engineering challenge that adds cost, or be forced into making a sacrifice which ruins the outcome because you had no budget flexibility. 

Section62

newhomebuild said:

HHarry said:

I spent £75k 15 years ago in North Hampshire and did most of the internals myself.

I reckon mclaren is right at £150k+

Gosh! Wonder how people finance this as first time buyers

The average first time buyer wouldn't embark on this kind of project.

If I'm reading the plans correctly (there appear to be some errors on the proposed ground floor plan) then the proposal is to remove the whole of the rear ground floor wall, along with about half of the external ground floor side wall. That's some ambitious engineering, given the only means of access apparent is the narrow passageway down the side.  Have engineering drawings been produced, or is it only the planning ones?

Removing the ground floor corner of a house is an expensive project, and in this case it is of questionable value given the side extension is only adding approximately 1m of width and on the ground floor only.  Better value could probably be obtained by extending further back (only), so long as there is space in the garden to do so.

I'd suggest you need to find out what the structural engineer thought of the buildability of the design, and how much the structural alterations will cost.  My expectation would be that the structural work will represent a significant proportion of the budget, making estimates of cost based on square meterage or typical extension projects unrepresentative of what this one might cost.

Furthermore, the side extension will be built over what appears to be the only access to the rear garden.  Unless there is another access, the project cost will also need to reflect the difficulty involved in carrying out building work on the rear of the property with no external access.  Would you be expecting to live in the property whilst the work is being done?

You'd also need to investigate how the drainage of the property works - as it is likely there is either a drain or a sewer in that passageway.  If it is a public sewer then consent of the sewerage undertaker will be required to build over it, and there's no guarantee that will be forthcoming.

If you need a property with more space than this one currently has then IMV you are likely to be better off looking for a different one.  There's no certainty the proposed work can be done as shown on the plans, and even if it can be, I'd have serious doubts about whether the economics make sense.

newhomebuild

Section62 said:

newhomebuild said:

HHarry said:

I spent £75k 15 years ago in North Hampshire and did most of the internals myself.

I reckon mclaren is right at £150k+

Gosh! Wonder how people finance this as first time buyers

The average first time buyer wouldn't embark on this kind of project.

If I'm reading the plans correctly (there appear to be some errors on the proposed ground floor plan) then the proposal is to remove the whole of the rear ground floor wall, along with about half of the external ground floor side wall. That's some ambitious engineering, given the only means of access apparent is the narrow passageway down the side.  Have engineering drawings been produced, or is it only the planning ones?

Removing the ground floor corner of a house is an expensive project, and in this case it is of questionable value given the side extension is only adding approximately 1m of width and on the ground floor only.  Better value could probably be obtained by extending further back (only), so long as there is space in the garden to do so.

I'd suggest you need to find out what the structural engineer thought of the buildability of the design, and how much the structural alterations will cost.  My expectation would be that the structural work will represent a significant proportion of the budget, making estimates of cost based on square meterage or typical extension projects unrepresentative of what this one might cost.

Furthermore, the side extension will be built over what appears to be the only access to the rear garden.  Unless there is another access, the project cost will also need to reflect the difficulty involved in carrying out building work on the rear of the property with no external access.  Would you be expecting to live in the property whilst the work is being done?

You'd also need to investigate how the drainage of the property works - as it is likely there is either a drain or a sewer in that passageway.  If it is a public sewer then consent of the sewerage undertaker will be required to build over it, and there's no guarantee that will be forthcoming.

If you need a property with more space than this one currently has then IMV you are likely to be better off looking for a different one.  There's no certainty the proposed work can be done as shown on the plans, and even if it can be, I'd have serious doubts about whether the economics make sense.

wow thank you so much for the detailed write up. I thought because planning was approved, that the project was feasible without any issues. Didn’t realise there could be other potential roadblocks as you mentioned. I think you are right, I’ll look for something else. Merry Christmas!

Section62

newhomebuild said:

I thought because planning was approved, that the project was feasible without any issues. Didn’t realise there could be other potential roadblocks as you mentioned. I think you are right, I’ll look for something else. Merry Christmas!

No, the planners will only consider feasibility issues if it affects something which is essential for planning consent to be granted - for example that roads/driveways meet minimum standards and any proposed parking spaces are big enough to park in.

Otherwise it is assumed the developer will find a solution to the technical/economic issues - it isn't a planning issue whether or not the developer can afford the work required to make the project work - in most cases it is just a matter of how much it costs.

Merry Christmas to you and all yours too.

Rosa_Damascena

newhomebuild said:

HHarry said:

I spent £75k 15 years ago in North Hampshire and did most of the internals myself.

I reckon mclaren is right at £150k+

Gosh! Wonder how people finance this as first time buyers

Are you nuts? Consider yourself fortunate as a FTB buyer in London, it's an excellent first step as it's a very hard market to break into. I bought my first home in Greater London in 2001, 17 years later I sold up and moved to a much bigger property in the 'burbs, and 3 years after that - ie this year - built a whopper of an extension which would not have been possible without the equity that came from crazy London prices.

Typhoon2000

Yes the the ground floor extension side extension seems to add very little to the project. Dropping just the side extension would probably save £50k, maybe more. And you would loose only the downstairs w/c or utility ( you will have space for 1 or an other) and about a meter width from the kitchen.  I can’t imagine there would be any problems getting the altered plans approved if it results in a smaller development.

GDB2222

In outer London, property sells for around £500-1000 per sq foot. On that very simple measure, the side extension will add around £10k value. It will clearly cost much more to build, ie several times the added value.

It is a very good question why these plans were drawn up? I guess that the present owners discovered that they made no economic sense, and decided to move. I’m not quite cynical enough to think that the plans were drawn up purely to fool a naive buyer. 

Doozergirl

Typhoon2000 said:

Yes the the ground floor extension side extension seems to add very little to the project. Dropping just the side extension would probably save £50k, maybe more. And you would loose only the downstairs w/c or utility ( you will have space for 1 or an other) and about a meter width from the kitchen.  I can’t imagine there would be any problems getting the altered plans approved if it results in a smaller development.

It makes me really angry when designers do this.  They just draw and don't consider the customer's budget - even if that house were owned by a multi millionaire, I'd be telling them that the side extension is adding nothing but costing greatly.  They just end up getting paid again when someone finally tells the owner that they've designed them a expensive downstairs loo.  

Big square, plonk a kitchen down one side, table over there.   Whacking great dead spaces all over the place but we definitely need to take out two sides of the house for the sake of a corner kitchen unit that detracts from a decent kitchen design anyway.  

I wonder how much the vendors paid for someone to draw them a box.  

TELLIT01

The current owner may not have costed the work, but applied for planning permission anyway.  Once they had planning approval they may have had a shock at the cost and binned the idea.  There are times when an extension is the best way forward but others where moving house is the more cost effective option.

Rosa_Damascena

Typhoon2000 said:

Yes the the ground floor extension side extension seems to add very little to the project. Dropping just the side extension would probably save £50k, maybe more. And you would loose only the downstairs w/c or utility ( you will have space for 1 or an other) and about a meter width from the kitchen.  I can’t imagine there would be any problems getting the altered plans approved if it results in a smaller development.

BUT unless the side extension is built, the double storey aspect ain't gonna happen.