1. Your home's roof should be inspected at least twice a year, both from the outside and inside the loft. If you can see daylight in the loft, there's probably something missing on the outside. Roof tiles or slates that have broken, slipped out of place, or been blown off are a common occurrence. If they're not replaced, rainwater will get into the loft and cause damage there and then the rooms below. Water staining in the loft is an early warning sign of a problem with the roof covering, so get it looked at by a reputable roofer straightaway.
2. Other parts of the roof can cause leaks and damp, including the flashing, guttering and chimney stacks and pots. You may be able to spot these problems yourself, but you will usually need a roofer to put them right. If you don't know when the roof was last maintained and you're not sure what to look for, or you can't see the roof properly from the ground, it's a good idea to get a roofer to check it over.
3. Perhaps surprisingly, most thatched roofs need little maintenance and, apart from having the ridge redone, can last up to 70 years. While thatch is idyllic, it's also expensive and carries the danger of fire. There are ways to reduce the risk of a fire, including having any working chimneys swept regularly (at least twice a year) and lined; making sure the chimney stacks are in good condition, especially in the loft; and having the wiring throughout checked by a qualified electrician every five years.
4. Flat roofs also have a bad reputation, but for leaks rather than fires. They're prone to leaks because they should have a gradient, but the gradient often isn't steep enough. If the roof is too flat or doesn't have an adequate structure or materials under the roof covering, it will sag, allowing rainwater to pool and eventually enter the room below. The roof covering can also get damaged, so it's something to keep an eye on.
5. Green roofs are covered in plants (with other layers underneath), instead of traditional roof coverings. They have lots of benefits, including absorbing rainwater, encouraging wildlife, and reducing pollution, sound transfer and heating and cooling costs. Green roofs can last around 50 years (both flat and sloping roofs are suitable), but installation costs are high.