If your existing asphalt roof is damaged, you can either tear it up and replace the whole roof or install new asphalt shingles over the existing ones. This latter process is known as an overlay, and it has several advantages over full replacement. Here are three examples of these advantages:

It Is Less Risky

An overlay is less risky for everyone involved, from the roofers to homeowners. For example, you don't have to worry about heavy dumpsters damaging your lawn since there are fewer materials to cart to the landfill. The fewer materials are removed from a roof, the lower the risk of accidental damage (for example to your car) or injuries (to your household members including pets). Of course a roofing company will have insurance for such purposes, but it is much better for everybody involved if there is no accident at all.

It Is Cheaper

Many people who choose an overlay over replacement go down that route because it is cheaper, As long as the rest of the roof structures are still sound, you can save as much as 25% of a new roof by choosing an overlay. Here are some of the reasons an overlay doesn't cost as much as a replacement:

  • Less roofing material; for example, you won't have to install a new decking if the existing one is still sound.
  • Reduced labor; for example, the cost of demolition is lower since you don't have to tear down the whole roof.
  • Fewer materials to dispose of; disposal fees and transport costs are lower since you don't have many materials to dispose of.

It Saves Time

Lastly, an overlay will also save you time since you don't have to go through all the process of installing a new roof.  Other time-conscious scenarios in which an overlay can save you include an impending sale, vacation or inclement weather (such as the storm season) where you need the new roof to be up as soon as possible. 

An overlay is beneficial and should be considered if you haven't been as keen as you should be with your roof maintenance, and you have just realized that it's damaged beyond small repairs. 

Not all roofs can benefit from an overlay; some must just be torn up and replaced. For example, it may not be suitable for roofs that have underlying issues or have previous overlays; there are a maximum number of times (a maximum of two is advisable) you can refresh your roof via an overlay.