Your roof is what keeps the temperature inside the house leveled. It protects the house from being rained into or having sun come in and even keeps animals and noise out. It is important to take care of it just like any other part of your house. Roof maintenance will help regulate your roof and keep it lasting for longer.
Roof maintenance is when a contractor will go up on your roof and check for sagging spots, rot spots, missing shingles, puddles and other things like that. If you have sagging spots it could be from the heavy weight of the snow. This is not good because it means that your entire roof could cave in. When the sagging occurs that means that the whole roof area surrounding it is weak and could even be rotting. This could be due to missing shingles or just melting snow after a heavy fall. Your house can take some weight but it is best to have it checked on after a snow fall or before the rainy months start.
If the roofers find something wrong such as loose shingles that are letting moisture into the house they will replace those shingles and the surrounding shingles to make sure that everything is back to normal. If it seems to be a bigger problem than that, they are going to have to take out the affected area and rebuild your roof.
You CAN however avoid all of this by putting a protective waterproof shield over the roof as you put it in and then renew it every so often when it starts to wear off. This will seal the roof and allow you to feel confident that no water will be able to get into your roofing and rot away at your roof.
There are many more maintenance tips you can learn from talking to your local contractor. It will save you a lot of money in the long run to simply have your roof checked once a year. It may be an initial lump sum of cost but in the long run it will be better for you to avoid major spending and time consuming hassle.