I'm a developer and i'm working on a particular php project.
As a contractor, Is it inappropriate to bill for meeting time? Meetings that consist of clarifying scope and intent of work?
Or is it not an issue at all? If so why is this?
Meetings are part of the job - part of working.
Part of your job is to clarify scope and intent of work - you wouldn't be very effective if you didn't do this.
Of course you invoice for meetings - you wouldn't have them if you were not working.
Don't confuse the end product of your work with how you get there - for example - as a developer, your job is not to crank out code. It is to solve problems - if you don't know what problems to solve, any amount of code you write is worthless to your client. Going to meetings in order to find out what the right thing to write is a much better use of your time than writing code that nobody will use.
If its a normal pre-sale meeting, your expenses are considered as part of the cost of doing business so don't bill them for it. Well, that's unless you don't really want the job or they were literally begging you to take it and you told them that you would in advance.
Any meetings AFTER you have signed the sales contract would be billable if your contract has provisions that allow you to treat any meeting/travelling/etc time as billable. If your contract doesn't have such provisions, it would be wise to consult with the client and get it clarified before you do. The last thing you want to do is to assume you can just because it "feels right"
Those meetings sounds like they are an important part of your job, and you should have no bad feelings for getting paid for those.
If you are lucky you the project owner understand the importance of the meetings and paying for them is no issue at all, but it could be that the project owner would like to "save" money by trying to have as little meeting activity as possible, thereby making your job more difficult as you probably will start with unclear scope etc.
If that is the case you might for instance want to charge less for meeting time as opposed to programming time so that the project owner gets the feeling that it is cheaper to talk with you to clear things out than you trying to figure out things by yourself.
The simple answer is that you should charge for meetings. You can't do your job without some meetings. These could be in person, or by phone/Skype...
The longer answer is to check your contract.
Sometimes the contract specifically mentions meetings you must support/attend. The contract could also specify if you can charge for travel time and expense (subway fare, tolls...).
There is also the chance that the contract doesn't allow you to charge for some meetings, but those should be specified in the contract. They may only allow you to charge at meetings they specifically ask you to attend.