Never assume that a gaping hole in the centre of your home's roof or a huge water leak inside the home are the only signs that the roof itself needs repair or replacement. Very often a roof will suffer damage that is not as severe as a huge hole in its middle, but which can still result in water leaks inside the home and in letting out your heating and cooling throughout the year. Note a few signs that your home's roof is in need of repair so you can ensure it's always in good condition and that your home is protected from water damage, mould and the like.
If you notice areas or patches of very dark shingles on your home's roof, this often means that those shingles are absorbing water rather than letting it run down the roof. This can cause those shingles to crack or even come away from the roof; this also holds water next to the roofing materials, which can then allow mould to grow or allow the roofing material to rot and decay. If you notice any such areas of dark shingles on your home's roof, inspect those shingles carefully for water damage or swelling, and then replace them with new roofing supplies, along with any damaged building materials under them, as needed.
Stains on interior walls
A plumbing leak can cause your home's interior walls to absorb water and then become stained, but if a roof has holes and is allowing water to seep into the home's framework, this can also cause those stains to appear. If you've ruled out leaking pipes behind your walls as the cause of these stains, have the home's roof checked for holes or other such damage.
Lots of debris on the roof
You may be surprised to learn that tree branches scraping up against a home's roof can actually cause damage to the shingles, even loosening them so that they blow away in a strong wind. This is why it's good to keep tree branches trimmed so that they're not hanging over the roof. Also, check the roof and the gutters for debris that may signal that tree branches are too close to the roof because the debris itself can cause damage to roof shingles and tiles. If you notice lots of leaves, twigs, acorns and seeds sitting on the roof, stuck between shingles or in the home's gutters, this can signal potential damage to the roof itself. Have the roof inspected and then repaired as needed if you notice this build-up of debris.