How do I know if I really need a whole new roof or can I just get away with adding another layer of shingles? That is a question that gets asked daily in certain parts of the United States.
Why only certain parts of the country?
Well a big factor in the equation is the weather. In the southern, warmer less humid, parts of the country, Southern Utah, Nevada and Arizona for example the weather is so dry that there is no real fear of humidity causing rot to the roof in normal situations.
If you live in an area with high humidity then there is an increased chance that your roof will have at least some moss on it , this is a sign of damp and high water levels. This can also be accompanied by areas of rot in the roof. The bad news is that often the only way to find out if you have rot in plywood layer of your roof is to rip of all the shingles and then look.
When most people consider roof repair they think along the lines of the old saying “Out of sight out of mind”. Just putting on another layer of shingles may seem easier and quicker but if you are just covering up some rotten roofing boards then that problem will grow. If you leave rotten wood untreated then the next problem you have will be a collapsed roof rather than just replacing shingles.
The main factor with many home repairs is “How much?” that is the first and last thing that many people think about and it is a mistake. Putting a new layer of shingles on your roof without taking the old ones off first will save you some money, you don’t have to pay for the labor or the removal of the waste. However if you are just covering up rotten wood then that will collapse eventually and then the costs could be immense.