How to get prices for a loft conversion?

[DaKid]

We've just got planning permission (home counties area) for a loft conversion and second-storey extension, and I'm after some advice on how to get realistic prices, please.

We currently have a square box 8.5m x 7.5m with a four-hipped roof and a 4m single-storey kitchen extension coming out the back. The permission is for replacing the entire roof with essentially a gable-ended roof and two large dormer windows, which will then contain en-suite bedrooms for our daughters, plus a second storey on top of the kitchen for a master bedroom suite.

Our architect(ural technician) will hopefully be providing some detailed plans for builders to quote from (he's about to retire ... need to speak very nicely to him to ask him to continue with our project).

The thing I'm really hoping to avoid is an overinflated quote from a main contractor who will just do everything for us. While I'm moderately handy at DIY I'm under no illusions about my ability to do the job myself, however my wife stopped working to look after our kids but they are now both at primary school (almost secondary school). She used to be a manager and so we have ambitions of hiring independent contractors and then managing the build ourselves.

The two question then, really, are ...

A. How much more expensive (percentage-wise) on average would a main contractor be compared to getting individual trades in? (i.e. is it worth it)
B. How, without the experience of a main contractor, can we know which trades to get in? (i.e. how many unknowns are there)

For the latter, it seems fairly obvious that we're going to want a small general building firm for the majority of the work, but will it be viable to just go to each trade (brickies, sparkies, chippies, etc) and ask them from the plans to quote for "their bit"?

Really appreciate some advice here, after we feel we've paid over the odds twice now for two previous building projects, and we're happy to try to take on a little more stress for potentially a lot less cost!

 

[Notch7]

For the latter, it seems fairly obvious that we're going to want a small general building firm for the majority of the work, but will it be viable to just go to each trade (brickies, sparkies, chippies, etc) and ask them from the plans to quote for "their bit"?

Really appreciate some advice here, after we feel we've paid over the odds twice now for two previous building projects, and we're happy to try to take on a little more stress for potentially a lot less cost!

Your job is a difficult one to self project manage, because it involves stripping off the roof off the house roof and extension, building the second storey on the kitchen extension, then a new roof with dormers, then new tiles

It is a very different project from an extension where all the work can be kept separate from the house.


A builder who would do the whole job will have loyal subbies that he knows, trusts and can call on to come to the job as needed. And they will be guys who know each other.

You however have no contacts, and any that you do get, you won’t have leverage to get them there when needed….and you won’t know when they are needed as you aren’t experienced in construction.

I think you could maybe get the shell built by a builder, say demolition, roof, brickwork and then get your own trades like plumber, electrician, plasterer etc etc. Don’t get a building contractor, get a one man builder who has like a couple of regular guys always with him - he will be somebody on the tools and managing the project + he is likely to do one job at a time so when he starts he will be there full time.

Be aware your project will need electrician and plumber early on to decommission existing where needed, then return when the shell is built and sealed in.


My advice would be to have a look around your neighbourhood and look at any building work happening, like extensions, then pop in and ask for some contacts, or ask the builder if it’s something they could do. Do not go anywhere near the internet (mybuilder rated people etc etc ) for finding tradesman

 

[DaKid]

Thank you .... that's some great advice. Really appreciate it!