Strenghtening or fitting new joists flooring

[robert73]

Hi All, I live in West Midlands and I was wondering how much does cost for strengthening/fitting new floor joists for a 2 bedroom house. The measurement are around 6 m by 4.5 m. If you could give me an idea, it would be great as I am looking for someone who can do a job by steps as I am going to do almost myself as DIY. thanks in advance

 

[big-all]

heeelllooo and welcome robert73

are you talking loft ?
first floor ?
ground floor?
or whole house ?
you seem to suggest a diy job and also someone to do it as well i suspect you mean a mainly diy job ??
its just not quite clear ??

 

[robert73]

Right it is a 2 beds house, ground floor and first floor. At the top I have got a roof space which I would like to convert it. I was wondering I much it will cost me to strengthening a floor joists on the loft by a builder. I would like to make things right and properly. However, I am good at DIY and other things such plumbing, put the boards down, insulating, making partition walls, I can do myself without problems. I believe electricity I can do it but I cannot connect them as I need a professional electrician to do that, but doing the main job, like putting through wires, I can do it, am I right?
I just need to find out by a professional, how much does it cost to strengthening joists, also fit a small dormer window (already made, just need to add on the roof) and two velux window and a winding staircase. If someone is so kind to give us an idea so we know when we get some quotes we know we are on the right track.
Thank you.