Bathroom Reno and Low pressure to sink

My wife and I are currently renovating a main bathroom on our 2nd floor.

We installed a new tub, and a new faucet set. My Dad did the plumbing for us which was simply positioning the new faucet set, and adding copper pipe to the hot and cold where needed, solderng it in place, and adjusting the tub spout and shower spout and soldering them in place. No problem...

However we are noticing that the water pressure in the sink in that bathroom is extremely low. The tub seems ok, as does our other bathroom off the main bedroom is more or less ok (my wife thinks that the pressure in the sink there is less too. I think it's ok..)

So what could cause the sink in the main bathroom to loose such pressure. Any thoughts?

First, take off the aerator and make sure it's not clogged with debris.
If that's not the problem, look for kinked supply lines. Next, take the supply lines off the "stops" and make sure the flow through the stops is adequate.

Thanks Steve

Someone on another site mentioned that when running hot and cold into a single faucet unit with a single handle, that you may need a pressure boost to the system. I was wondering if this is true, and how that would be done. Because that is exactly what our new bathroom tub/shower is using, instead of the older two knob system.

Thanks for your help

Older faucets were not flow restricted...nearly all of the new ones are. Just like showerheads, faucets are now limited in their flow which would appear to be low pressure (which, in a manner is). When the faucet is closed, the pressure is the same as everywhere else in the house, but think of it like a hose where you only open the faucet a little. If you cap off the end of the hose, the pressure is high, but then let things go, and you only get a limited flow. This is true for a faucet whether it is a single handle or double.

Thanks for the advice guys. It actually was the Aerator...

I took it apart and on the faucet that was really bad, there was a fair size piece of a wood shaving in there. I took it out, and found some very tiny tiny bits of solder that must have come loose. I cleaned it up, and it works fine now. Thanks again for all your help

You're welcome! It's amazing how much debris gets into the water supply system when work is being done to it.