make sure you discuss the aspects of planning requirements fully with your chosen installer prior to starting any work.
If you want to know more about the benefits of replacement windows here is a guide: Double Glazing Vs Triple Glazing? – The Pros & Cons
spend the time to source for the best resources, you will be able to find a few good deals.
Before you purchase from any contractor, you may want to find out more about the products that they are offering at www.localconservatoryprices.co.uk/lean-conservatory