Steve has been involved with the building industry for over 35 years. We have compiled a list of the questions he gets asked most often by clients and prospects. These questions come from both returning clients and clients who are embarking on their first development project.
The answer to this is that you should discuss this with your construction partner, however this question really should be "should I consider supplying fixtures and fittings?" Depending how involved in the project you want to be, then this could be an option for you. While on the surface, due to percieved savings this looks attractive, in practice it can be a recepie for stress, more stress, disaster, then added stress. Most fixtures have specific requirements in relation to fitment. That means that as well as sourcing the item, you will have to make sure that these requirements are passed to your construction partner, and it is your responsibility to ensure that these requirements are met pior to install. You may also find that the supplier needs to undertake a survey prior to manufacture, your builder has to be available and have completed the required works prior to his visit. You will have to make all of the arrangements, and be responsible for any repeat visits if required. If your builder is not made aware of these requirements and is constructing according to plan, then any issues that turn up at the time of pre-installation survey, or installation itself then there may be additional cost and certainly time that now needs to be added into the project to accommodate. Manufacturing timescales, delivery, acceptance of delivery etc. and if delivery also includes installation also needs to be taken into account. If you are sourcing the item, then all of these now become your problem (as do any warranty issues) rather than your builder.
Most construction partners will be happy to work with you around this question, some will be happy to delegate the responsibility, and pass the purchasing to you, others will be less comfortable with this arrangement because they know that the responsibility for issues / remediation / warranties will become a major issue in the event of problems, as will the any remediation as this may impact his project plan. If you want to go down this route, then by all means discuss this with your partner, however you should be aware of exactly what you are getting into.