Extension - one builder for all or project manage ourselves?

[Lamby80]

Hello,
We are finally in the process of drawing up plans for our extension - hurrah!
We have been talking over the weekend about the possiblity of managing it ourselves. So, someone to do the foundations, then a bricky for the build etc, electrician..... I suppose the list is endless.
Has anyone done this? The main drive would be to save money, but if there is not a massive saving to be made, then I probably wouldn't give myself the hassle. We both work full time with young children. If we used a builder for all, it would mean pushing it back a year.
Thanks.

Would you have the capability of managing how all the different trades relate to each other and understanding what needs doing when? Do you have contacts for the different trades - a builder doing it all will know who he likes to work with. You would probably also be responsible for setting things out. Generally I would advise against, particularly if you do not have much time.

I don’t think you’d save as much as you think once you account for all the missteps that might/will occur in terms of dovetailing exactly when each person needs to do their bit etc. Also I think you might get a better finish if the builder works with those he knows and likes as they’ll be trying to help each other out. I’ve just done a small project and used a builder and his mates for first fix and kitchen fitter separately, two people was enough to coordinate (with small kids and a job) I wouldn’t want to project manage each trade on a larger project.

We are at the end of a building project to build an extension and found it better to have builder project managing the whole lot as he has the contacts with all the other trades and coordinated the whole process of who did what and when. They then liaise with us
We were recommended this builder by the architect who drew up the plans and liaised with planning dept for us. We had about 12 builders altogether who
came to discuss the work and what they could offer us - we had a set of questions that we asked all of them, some we learnt as we went along. One question was about if they'd have access to other trades people and how they would manage the whole process.

When it comes down to they know trades people more than you or I would ever do - it's not our sphere of knowledge. This way will be less stressful and save you time and money.
We got about 10 quotes and went for the builder we trusted and liked the
most as ultimately you have to get on with them as they're in your house for the next 6 months or so.

Sometimes if you have several different teams working independently on the same project, it can be difficult to get anybody to take responsibility for any problems that arise later. So if, for example, a cracking appears in the extension wall and you call the builders back to sort it out, the builders may blame the person who did the foundations, and the foundations person will tell you he was only following the structural engineer's plans, and so on...

If you're going to project manage it yourself, you've got a lot of responsibility, even with a small domestic extension;

• Finding builders for each trade
• Negotiating a price with each builder
• Coordinating each builder to be on site at the right time e.g. having the electrical and plumber doing their pipe work/cabling before the plasterers line and skim walls, then getting them back to do radiators, faceplates etc
• Sorting it out if someone is late/gets it wrong/etc
• Paying them all individually
• Being available to fix problems/discuss things/etc when it needs done

Yes, you'll pay more for a 'one stop shop' builder, but personally, I think the additional cost outweighs the hassle. Especially as a full time worker with, I assume, no experience of construction.

You won't take your own appendix out if you weren't a surgeon, so you probably shouldn't project manage your own build unless you know exactly what you're doing 🙂

We managed our own for a refurbishment but my mum manages projects and knew what order things should be happening in, that's the only reason I went ahead.

I think materials are a major consideration if you want to manage it yourself. Are you buying your own or will each trade bring their own? Are you prepared to coordinate deliveries of materials for each trade? If something is late for the plumber it will delay the plasterer etc and then plumber will be ticked off as he has lost a day's work. If you are on site you can probably coordinate this but if you are both working I think it will be a challenge and may be worth just getting the builder to oversee it all.