Home improvements such as adding a conservatory can cost thousands of pounds, so it makes sense to know a bit more about the installer before you award them the job.
To know that the installer has been pre-vetted by an independent 3rd party for financial stability, skills & track record is one way of lowering your exposure to dealing with a poorly rated company.
The main stream double glazing trade associations provide a good guide and measure of an individual company competence, whilst also offering good levels of industry specific consumer protection benefits.
whilst not a complete list, the ones shown below are considered to be amongst the most recognised in the double glazing industry, thier website links are given below & you can visit them to find out the specifics of their membership criteria.
There are also several other trade associations linked to the home improvement trade, each one with its own merits. Always ask your installer which trade association they belong to and how long they have been members.
A sure sign of a good company is if their previous customers are happy to recommend them. Any reputable company will be more than happy to provide references and in most cases they will be happy to put you in contact with them.
Unhappy customers can also be a good guide, especially where the installer has hit a snag (most will at some time or another), and the customer was dealt with promptly and to their satisfaction.
This can sometimes say more about the installer, in that they are prepared to look after their clients after the inital building work has finished.