Recently a large 6' x 4' section of shingles slide down the south side of the roof exposing the felt paper below. The original roofer is long gone. We called out another well known roofer in the area to inspect/repair the section that fell.
His immediate reaction was that the roof wasn't nailed correctly. He threw down a section of shingles and showed us how the nail heads had pulled right through the shingles. He explained that there is a nail strip where you are supposed to nail into the shingle. These were nailed several inches above the area where he said was the proper place.
Only the south side has been effected so far and to be safe and sure we are going to have the entire roof replaced again.
The question I have is about the underlying wood and kind of shingles we can use. The roofer who came out and told us about the nail strip suggested that if we want to use an architectural shingle again that we re-sheet the entire roof with new wood. He says that the nail strip on an architectural shingle is too narrow and would need new wood. The nail area on a 3-tab is much larger and would not require new wood to nail on.
Another roofer says that's BS and if he did encounter any spots that were questionable, he would only re-sheet that area. The difference is about $2000 to have it re-sheeted or not.
Any other opinions? We'd really like to keep the architectural shingle look but are not sure whether or not we need to re-sheet the entire roof as the first roofer suggested. As I said above the wood is in good shape and there are no soft spots anywhere.
Todd