To choose the type of roof covering can be hard. You will find looking at surrounding properties will help. If you live in a terraced house, or one of similar age, a slate roof will usually be what was on originally and probably still will be. If it is a modern property then it may have tiles on the roof. Sometimes your budget wont stretch to replace your roof like for like. Plain tiles for example. So you may have to choose a cheaper option.
When you are looking to pick your roof covering, take your time, as there are plenty styles, colours and manufacturers to choose from. (Links below).
For slate, speak to your roofing contractor and discuss budgets. Or contact your local roofing stockist and check what specific slates they offer.
If you are choosing slates, be aware, cheap slates are a false economy. The old method for extracting slates was to use a chisel to split the slate with the grain. Modern methods usually cut as many as possible from a piece, regardless of grain. The majority are imported from China, Spain, Brazil, and many should of been left in the ground another million years or so. As they break and split with ease.
To get slates imported into the UK they have to meet certain criteria. Unfortunately, to get around poor quality slates, they grade the slates and give them a life expectancy, the least being 20 years. So the criterion needed to meet this level is very low. The grades range from D (poor) to A+ (best), the problem being, a very poor slate, to a very good slate, will look virtually the same.
It is only when the roofer attempts to lay them to when you find out how bad they actually are.
Many clients will not realise there is such a huge difference in quality and price of slates. For instance a 24 X 12 (600mm X 300m) slate can vary from around £1.20 up to £8 per slate, with little difference in the actual appearance when new.
It is only 8-12 months down the line, when you look up and have missing slates, and many have faded different shades of grey that you will know how poor they are.
That is why it is imperative that you choose the right slate, as leaving it up to the contractor can cause future problems.
Also, many contractors will only see profit margins, so you may get a low grade slate without having a choice.
When slates arrive, the only way to identify them is the pallet / crate they arrive in. Once laid bare, there are no identifying marks.
To give you a heads up, and probably give you more information than many roof contractors, builders or roofing stockist have themselves. Here is natural slate classification chart compiled by SIG group.
My overall advice would be to spend some time and do your research. On average, a new roof usually costs from 2 - 5% of the total value of your home, so it is a big investment. You may not care as long as it does its job, or you may want the best you can afford. But remember, be certain, as once its on, you have to live with it.
If you would like any specific information, please do get in contact.
Please find below links to the major UK roof tile manufacturers - all products are viewable on their respective websites