How long does an architect take to draw up plans?

I am having a two storey extension on my house and got an architect to measure up and agree to draw plans. Six weeks ago.
Haven't heard a thing so far. Do I hassle and what do I say?
Answers:
Hi. Architects can take a long time, depending on the work needing doing. For a two storey extension it shouldn't take too long though. I'd give it until 2 months are up, and then ask them, but politely.

My suggested wording would be along the lines of:

"Dear [name]

I was wondering what the current status is with the design of the extension to my house. I have no idea how long these things normally take, but am starting to get anxious having not heard from you for two months. I do apologise if I am expecting things far too soon, due to my limited knowledge of the construction industry, but it would ease my mind to know what progress has been made.

Many thanks."

PS Having read someone else's comments: I wouldn't have a go at doing it yourself. The architect won't just be deciding what it looks like, but putting in services (i.e. plumbing, electricity), and getting a structural engineer (like me) to check that it won't fall down!
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It depends of if they can spell as well as you can.
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just mention it to him. "hey, i was just wondering if you have completed the plans yet"
It should not take six weeks to hear back from him, call him and ask how the plans are going, it takes a lot of work but six weeks with no word is a long time.
An architect can take anything from a day, a week or even a month. It depends on your foundations, they have to give some idea of calculations using pythagoras' theroum etc. The drawings then have to go through an engineer to be checked that the calculations are right, they are then generally passed on to yourself, or the workers.
I would be calling them. It has been long enough for them to have some type of plans drawn up for you to review.
There was a report commisioned by the UK government concerning all the parties within the building industry. I read the report, can't remember who compiled it (two researchers) but I was shocked and still am, 8 years on. The language they wrote in, concerning architects, was as close to verbal abuse as could be put in a report! They described them as living in the middle ages, withholding their professionalism so only selected recruits would be proficient enough. It said architects caused a lot of trouble all round because of their own self-interest.

Have a go at drawing yourself, I prefer TurboCAD to AutoCAD. Building work needs only simple drawings and you can do these with a bit of practice. I'd do them for you maybe but I don't put email details on this site.

Sorry - I didn't read that it was for something as critical as a two storey extension. I would still have a go though, at least for planning approval. As for deciding on foundations though, you can still get the design without the drawings, and do them yourself. Go straight to a surveyor or structural engineer. What they reccommend, draw and take to the building control as well as the planning department.
Soooooooo, the architect did come out and measure and agreed to do the plans. Six weeks ago is long enough. Just give him a call and say "Hello (his name) just doing a follow up to see how you are coming along with the plans". Then the ball is in his court. If you have paid him some in advance, then that may require a little more "hassle".
How long? about £20,000 i think..
Yes, Hassle or find another architect - it should only take four or five days actual time on the job so he's either too busy or dosn't really want to do the job for you