Design & Build

[pdf27]

Has anybody used the design & build route for their project, or does anybody know of anybody who has?

 

We had a builder come over yesterday to discuss our project and get a second opinion on a few things, mostly relating to costing and feasibility. One of the interesting things to come out of the discussion was that he prefers to go down the design & build route if given the choice - i.e. they tender to deliver the whole project once we've obtained planning permission and provided a reasonably detailed spec. They then take responsibility for the detailed design and deliver something close to a turn-key build. This builder seems reasonably clued up, is fairly local and has delivered a number of similar buildings before including at least one certified Passivhaus, and several of his points resonate pretty well with my own experience at work (I'm a mechanical engineer).

 

Doing this is obviously in their interests - it locks in the project management for them, for instance - but at the same time may suit us quite well. We've taken a while to get to the starting point here so my wife is a bit fed up with the whole process, and project managing it ourselves isn't on the cards due to other commitments (jobs and young kids). While we're happy that our architect will do a good job and deliver the design we want, their initial cost estimate included not far short of £100k in double-counted costs (they took a QS report from another one of their other projects then added in a load of costs that were already included but they'd assumed weren't without checking - so e.g. 10kW of PV got counted twice) so I would not feel very confident relying on them to supervise the build. Technically I'm happy that it would be fine, but I suspect the cost control would have issues. It should also be noted that we aren't very fussed about finishes, etc. - a few things we want are a step up from a standard developer level of finish, but we have young kids and are assuming that anything really nice will get destroyed by them so are working on the assumption that kitchen, bathrooms, etc. will be replaced in 10-15 years time.

 

The thinking is that we'll take it to getting planning permission with the current architect, who will also do PHPP, etc. for us. At that stage we'll have a full QS report as well as the planning drawings and so have something to compare a design & build tender to and see if it really is cost-effective. If we did go this route we'd probably also insist on it being a certified Passivhaus - that's up for grabs at the moment, and I think with this type of contract the additional quality control aspects would be particularly valuable.

 

Comments?

[nod]

Reading the above D&B route would be a good option for you 

(One point of contact )

While the tendering system can push the price down

It would be worth spending on a independent professional to compare the quotes As very often the lower quotes  have items missing 

[Gus Potter]

14 hours ago, pdf27 said:

Has anybody used the design & build route for their project, or does anybody know of anybody who has?

 

We had a builder come over yesterday to discuss our project and get a second opinion on a few things, mostly relating to costing and feasibility. One of the interesting things to come out of the discussion was that he prefers to go down the design & build route if given the choice - i.e. they tender to deliver the whole project once we've obtained planning permission and provided a reasonably detailed spec. They then take responsibility for the detailed design and deliver something close to a turn-key build. This builder seems reasonably clued up, is fairly local and has delivered a number of similar buildings before including at least one certified Passivhaus, and several of his points resonate pretty well with my own experience at work (I'm a mechanical engineer).

 

Doing this is obviously in their interests - it locks in the project management for them, for instance - but at the same time may suit us quite well. We've taken a while to get to the starting point here so my wife is a bit fed up with the whole process, and project managing it ourselves isn't on the cards due to other commitments (jobs and young kids). While we're happy that our architect will do a good job and deliver the design we want, their initial cost estimate included not far short of £100k in double-counted costs (they took a QS report from another one of their other projects then added in a load of costs that were already included but they'd assumed weren't without checking - so e.g. 10kW of PV got counted twice) so I would not feel very confident relying on them to supervise the build. Technically I'm happy that it would be fine, but I suspect the cost control would have issues. It should also be noted that we aren't very fussed about finishes, etc. - a few things we want are a step up from a standard developer level of finish, but we have young kids and are assuming that anything really nice will get destroyed by them so are working on the assumption that kitchen, bathrooms, etc. will be replaced in 10-15 years time.

 

The thinking is that we'll take it to getting planning permission with the current architect, who will also do PHPP, etc. for us. At that stage we'll have a full QS report as well as the planning drawings and so have something to compare a design & build tender to and see if it really is cost-effective. If we did go this route we'd probably also insist on it being a certified Passivhaus - that's up for grabs at the moment, and I think with this type of contract the additional quality control aspects would be particularly valuable.

 

Comments?

Float the idea to the builder that you may engage the same QS to maintain a watching brief on the "design and build" contract they offer you. I have seen this many times before and the contract offered is often not fair, equitable and reasonable unless they are at least sticking to a recognised standard contract adopted by the industry.  Make no mistake a good experienced QS or other professional is worth their weight in gold. A few well chosen words of advice can save you later... They may (QS) even give this advice for free. I do if able!

[Conor]

D&B is a good option, it's the default for big infrastructure projects. You do however need to have a very detailed and robust spec. There is an incentive for the D&B contractor to cut the spec and corners that the client won't notice. Therefore, independent inspection and signoff for stages is critical. If you don't know what type of plasterboard should be going in or what type of insualtion, then get somebody to check that for you. And make sure all parties know the spec inside out before singing and you'll get on grand.

Edited February 28, 2021 by Conor

[the_r_sole]

Hmmm... wouldn't d&b my own house.

A contractor will be doing the day to day project management no matter what procurement route you are heading down.

I've never seen a house where changes haven't been made made after the contractor is on site and that's difficult in d and b.

The advantage of d and b is being able to start early and with some cost certainty (as long as your requirements are clear enough), the thing where it always fails is quality, look at any public project where they've found major

 defects and generally they'll be procured through d and b. 

If you are leaving the contractor to detailed design make sure they do post completion testing and assume all responsibility for regs/completion. I'd also want someone doing independent inspections very regularly. 

For one off houses I'd always want a traditional contract with either the architect or a qs doing the contract administration (nothing to do with project management) with a very detailed set of drawings and specifications forming the agreed contract...