Look at how you use your home now, what are your frustrations and what you do and dont like about your home, how you want to use your home and determine what your total budget will be. Then come up with a list of must haves and nice to haves, along with an idea's book so that you architect/designer know where you're aesthetics are leaning.
Think about bouncing off your architect any products your keen to have used (such as double glazing, solar panels etc) as they may impact on the design too.
I'd always go for an architect - they spend 7+ years learning how to manipulate space, light and the environment to get a great building and have an arsenal of tricks to turn negative spaces/features into positives.
A good designer will be able to offer suggestions and ideas that you may not have thought of. You should be able to organize a consultation with a designer early and get really good advise. A good designer is just as capable as a good architect. Some designers spend 6 years at uni learning a very similar trade as an architect. You really just want to find someone with a good reputation and track record of happy customers.
A good Interior Designer will be able to proved you layout options and scale drawings that you can consider before deciding on a final layout. They may also be able to do a 3D scale model so you can see what the new extension would feel like.
Interior Designers can also do Floorplan Layout Changes and are able to give you some very original ideas that you may not have considered before.
I recently was asked by a client to help with an architect drawing because it wasn't quite what they wanted. I was able to come up with options that worked better for them. Also an interior designer will be able to come up with a design including finishes, fixtures and fittings that will provide you with a complete list of finishes to give to your builder for pricing.
Either way the best thing to do is to create a design first as this may take some time to get right.
georgi02
User
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