Another extension question

Moneygrabber89

Here we go guys....sorry in advance.
Since my last thread I've spoke to a few architects and builders. The general consensus is that a double story extensions for length of house and going out 3.2 meters at the side is going to cost around £50k in Sunderland.
This extension would turn my 3 bedroom semi in a 4 bedroom semi with an ensuite and also adding a downstairs toilet.

So here's my question. My house cost 160k plus the 50k extension would take it too £210k. I was worried about loosing value but the other 4 bedroom detached properties currently on the estate are being advertised for £290k and these dont have a downstairs toilet or external garage!! Ours would he 4 bedroom semi detached with external garage. 
So my question is do you see my 4 bedroom semi being valued at 70k less than the detached home

tink_1983

How small will your garden be once extension done.
I personally value being detached, but for alot it's a negotiable 

Moneygrabber89

Wouldn't affect garden size! Our corner plot is by far biggest on street 

Doozergirl

Stop comparing to detached houses.  You don't have a detached house.  My old house was an extended 4 bed semi and would have easily been priced at 30% more had it been detached.  

The rough working out, as I said before, is to establish the price per square metre of your house as it stands and then multiply it back up by the size of the extended house.   If you are adding half the size of the house again, it would roughly equate to half the value again, so £225k, though smaller houses can have higher values per square metre, so I think you're in the territory of making little to nothing on the extension.  

Look at rightmove across the areas of town that equate to yours. Someone will have extended their semi in a similar way.   How much are they?  

Moneygrabber89

The architects and builders I've spoke to are saying the opposite but maybe they are just touting for business

Thanks guys

Moneygrabber89

The last 3 bedroom semi into a 4 in the area went went for 95k more for 2 story extension compared to 3 beds semi in that street.  The other 1 went for 65k but that was just extension on top of garage