My advice would be if you are thinking of using these people dont be missled by the name, they are just another conservatory company and from my experience not a very good one at that.

I contacted the NRWAS last October to have a conservatory built. We agreed to go ahead in November and made the first payment. A building survey was supposed to take place but after a number of calls to Steve Elsworth ( Elsworth construction and installation) to arrange it, he decided it wouldnt be necessary. The project manager ( Stuart Handley) said that would be fine. Building work started in January 2008. We had been told that the installers selected ( we were only given 1 to choose from) employed all of their own staff and didnt sub contract, the builders were all subcontracted. As a result of not having done a building survey the builders had no plans to work from. The first mistake they made was to pour the concrete slab over the air bricks of the house instead of installing conduit as we had requested. When informed of this they cut 2 channels in the floor to install conduit and then filled the channels in. They also had to remove the bricks surounding the air bricks to enable this to be done. We were left with 2 large holes which were letting rain and snow under the floor of the house. I informed Steve Elsworth of this problem and requested that it be fixed. Shortly afterwards the glasing was installed, then plasterers came to plaster the walls but the holes had not been filled. I gave the plasterers some bricks and morter and they agreed to fill the holes so that they could do the plastering.
I asked to have the floor properly levelled so that I could lay laminate flooring, 2 attempt were made at this but the floor was so uneven that the joints in the laminate floor broke appart. A third attemt has now been made but there are still raised patches.
As a result of not performing a building survey one of the conservatory door does not open fully as it its against the main part of the house.
Through all of these complaints the NRWAS have acted on the side of the builders and not the consumer as they claim is their role. They claim that all of their installers are members of registered trade organisations. I asked about Elsworth construction and installation and they told me they are members of the glass and glazing federation. The glass and glazing federation deny this.
We ar approaching 1 year since this process was started and we still cannot use the conservatory. The only thing in our favour is that we dont have to make the final payment until we are completely happy with the conservatory.