As designers we aren't always comfortable on the site, observing what’s going on.
But there are good reasons to do it anyway.
First: Most clients like the idea of having their representative looking after the construction work.
Second: We have had the experience of being blamed for screw-ups that the contractor created. Being involved protects your reputation.
Third: If the contractor is shoddy, your being involved could avert some unfortunate results. This is good PR.
Fourth: You make more money on every project by including CA.
CA is poorly compensated in most contracts and fee structures. So up front set a limit on the time that is included in your fee. Keep the client aware of how that allowance stands, and alert them when you have to start billing hourly. I lost money on every job until I hit on this solution. I had one client in 15 years balk, but even he begrudgingly went along because he saw the value.
The Construction Administration Phase usually starts when the contractor or construction manager receives a signed contract or a Notice To Proceed [NTP]. No two projects are the same, however the main tasks during this phase are:
This three-part article below gives you a more detailed overview and some additional resources.
Construction Administration Overview