Yes, it can happen often, unfortunately. We highly recommend you get them replaced though as this will prevent further damage to the roof structure.
Your first instance should be to call a roofing company such as King Roofing, so that they may survey your roof and recommend the correct course of action.

We would not recommend it at all. We see roofs being damaged far too often because of how strong the jet is.
King Roofing can clean your roof and gutters so please ask us about this service.

Treatment of rot is a fairly simple process, however, if the timber is damaged and needs replaced this is something we can certainly do.

We find most well-built roofs can last for approx. 20 years. It all depends on the materials used, for example, Slate tiles are known to last longer.
Of course, many factors dictate the length of time a roof maintains its integrity, such as the weather, which materials were used, how well they were installed initially and how well they have been maintained over the years. This is why you should always discuss the warranty of the manufacturers’ products.

We would strongly advise against it. Not only could it be incredibly dangerous for you resulting in inury, but you could also damage your roof further.

Generally not, we often complete roof repair service for our clients. Water can gain access from sections that have come loose or damaged by weather etc. There are occasions when the roof was installed poorly, this can cause the entire structure to be dangerous and would need to be replaced.

It doesn’t happen often but there are occasions where it would be best to leave the property for a period of time, usually due to the elements and or safety.

Well from our experience it’s not possible to give you an exact time line, if we look at a semi-detached property then we could say something like that could take up to 3 weeks to do the roof.