The average cost of a new roof in Los Angeles is $8,000 to $30,000. This is a big range of pricing, and your cost could be higher or lower depending on several variables. The first thing to consider is counter-intuitive: roof replacement costs on a larger house will often be less than on a smaller house.

The cost for roof replacement can be less when you have an overlay. With an overlay, new shingles are installed on top of existing ones. So you'll save on labor costs and disposal. That might be a good idea if the layers underneath are in good condition, including metalwork, flashing, and decking (sheathing).

If any are worn, curled, slipped or missing tiles, it's a sign your roof may need replacing. At the very least you should look to repair broken and missing tiles as soon as possible. Also, check the ridge of your roof. This should be completely straight.

So how often should you replace your roof in California? The answer depends on a few factors, such as the type of roofing material, the climate, and how well the roof has been maintained. In general, however, most roofs will need to be replaced every 20-30 years.