There's no two ways about it; if the roof needs replacing or repairing, it has to be done. There are no other options and unless you have extensive experience in this kind of work, don't even think about trying to tackle a job like this. Not unless you want to be living in a hotel for months on end. No, it's best you discuss your job with experienced roofers in West Wickham.
To find out if the West Wickham roofers are the right ones for the job, ask them to come and give you a quote. You would expect they would thoroughly inspect both the exterior and interior of your home for leaks or potential problem areas that may turn into leaks. They will check for rotting boards, areas of mold or weakened supports. If the roof needs repairing, they'd let you know and show you where it needs to be done and what needs to be done.
If you just have some minor leaks, you may be able to get by with caulking, but the professional roofers in West Wickham will be able to let you know what you need. If your roof needs replacing, then this is definitely a job for experiences roofers. Asphalt roofing needs to be done approximately every 15 years and wooden roofs usually every 30 years.