I am an architect in private practise, and have undertaken hundreds of projects since my first commission in 1966. I first met Ian Thompson of Prodek Ltd in January 2003, and after discussion appointed Prodek to lay a single ply membrane on the flat roof of an extension to a hotel in central London. Both my client and I were very pleased with the result, and the efficiency and speed in which the work was carried out. Since then, I have abandoned the use of three-ply felt and asphalt and use Prodek for all the flat roofs in my projects. None of these roofs have ever leaked, and accidental damage to the membrane is easily and cheaply repaired. A 20 year guarantee is given for all work, and the price is often much lower than asphalt with its requirement for floating fillets and lead cover flashings, which are not necessary with the Prodek system.