A “roof over” is considered to be O.K. in certain areas of the US. In this form of re-roofing a crew simply nails a new layer of shingles over an existing layer or layers of shingles. However, in a “roof over” situation there is no way of telling whether the decking has damage or needs to be replaced, plus the additional weight it adds to potentially compromised decking. You also have to consider the probability that the roofing material already has aged and broken down. The felt material breaks down over time and becomes inefficient. Overlaying shingles can also cause a ripple effect on your roof that would be very unappealing to look at. Make sure you know all of the facts about overlayment before considering paying a roofer to do a job that may cost you more in the long run.
Roof restoration can extend the life of your existing roof before your roof deteriorates through general ˜wear and tear or basic neglect. Restoration is largely appropriate for tiled roofs. Tiled roof restoration is commonly performed on tiled roofs that require re-bedding and re-pointing, have broken and chipped tiles or have discoloured or faded tiles.