Massively. I will tell you that I stupidly tried to plan a home extension on the hoof when I was younger. It cost me about five figures in repairs and restoration after the job was a mess. I also recommend that you hire extension builders in Sunbury who have lots of experience.
An inexperienced builder will make the mistake of just agreeing to what you say. This can lead to problems with the plan that do not match up with what can actually be created. For that reason alone, I recommend you take your time to get the extension planned out with a local professional. This is vital because they can give you an idea of where you might need to change your plans and what could potentially go wrong if you just hope for the best.
Planning, then, is a non-negotiable step!
