A residential roof has many potential weak points. The chimney is definitely one of them. This is particularly true on pitched roofs. Along the top side of the chimney, the angle of the pitched, where it meets the chimney, can create a situation where standing water is inevitable. Obviously, this vital joint will be built with metal flashing to help fight against moisture damage, but it can still be a potential weak point on your roof. In fact, if you do have a leak coming through your roof near the chimney, there is a good chance that this is the source of the problem. This article explains how to perform chimney inspections and repair it if necessary.
Getting Up on the Roof to Have a Look
Unfortunately, you can't really check your chimney unless you get up on the roof and look at it up close. Obviously, if you have fragile clay or terra-cotta tiles, you need to be very careful when walking on your roof. In fact, you should be careful walking on any pitched roof. If there is a problem with your flashing, you can often tell as soon as you look at it. But, with some hard tiles, the flashing underneath might be damaged, even though the tiles seem to be in perfect condition. You might need to light a lift up the tiles and then use a flashlight to look at the flashing to see if it is still firmly attached the roof deck and not peeling up along the edges. If not, it will need to be repaired, and you will need to remove some of the tile.
Calling a Roofing Specialist
If you don't have the skills or tools to do this, you should just call a roofing specialist. Let them know what your problem is so they can come and make the repairs without having to waste their time and money on an assessment visit. If your chimney is leaking, but it doesn't seem like the flashing is the source of your problem, then there could be something wrong inside the actual chimney flue. Similarly, this is a project that will be very hard to fix yourself if you don't have experience working on chimneys.
You will certainly want to fix any water leaks new chimney as soon as possible. Roofing repair is usually affordable, but it gets costly and there is water damage to the deck of the roof. That is, since the roofing material needs to be removed before the deck can be properly repaired, the projects can become very expensive.