Posted on: 8 July 2018
Replacing your old roof is often a better choice than adding a new layer of shingles. If your home already has two shingle layers, then replacing the roof is usually necessary due to the added weight of an additional roofing layer. Even if your roof only has one layer of shingles, replacing it could be a better decision than adding a second layer. Here's why.
Old Materials Are Stripped Off
Removing all old shingles and the felt down to the deck has its advantages. It gives the roofer the chance to examine the deck thoroughly for damage. It's better to find and repair damage than it is to just cover it up because that increases the risk of your roof leaking in the future with you being unaware.
Also, you may want the roofer to pull out the old nails and put in new ones that have improved anchoring ability. If your roof is old, roofing techniques and building codes may have changed that require the use of different decking nails that hold roofs more secure in high winds. Talk to your roofer if this is an option you want to consider.
New Underlayment Is Applied
When you have your roof replaced, new underlayment is put on too. This layer of felt plays an important role, so it should be in good shape. It acts as a barrier between the shingles and the deck so it can help control leaking. It also helps shingles to lay flat against the deck when the felt is smooth and in good condition. In addition, the underlayment acts as a vapor barrier that protects the shingles, so they have a longer life.
If the felt is old and degraded and you apply a new layer of shingles on top of the old, the new shingles might have a shorter lifespan than you anticipate. By ripping off the old felt and putting on the new underlayment, you ensure your roof has the best chance at a long life, so you get a good return on your investment.
New Shingles Are Installed On A Flat Surface
Once the deck and underlayment are ready, the shingles can be applied. Putting shingles on a flat surface that's properly prepared ensures the roof has the best visual appeal and that it is durable and resists wind lift. The problem with old shingles is that they curl, have repaired areas, or have missing granules that make the surface of the roof uneven.
While a roofer shouldn't put on a new layer of roofing unless the old layer is suitable for it, if you take the old layer off, then you can eliminate the risk of problems it could pose with the new shingles.
Having your old roof replaced costs more than simply putting on a new layer of shingles, but the cost is usually well worth it. You might get a longer life out of the shingles which will save money in the years to come. For more information, contact a company like A&W Custom Carpentry and Roofing.Share