Trusted Concrete Repair, Replacement & Resurfacing Contractors in Rockville, MD

1. It places unnecessary strain on the roof structure. Roofing systems can only bear so much weight. By nailing a new layer of shingles over the old ones, you’ll be straining its weight-bearing capacity to the limit, which can cause the entire roofing system to bow or sag. 2. It makes your roof susceptible to wind damage. Because the new shingles don’t adhere to the roof quite like they should, they can be easily be blown off by high winds. 3. It compromises the attic ventilation. The additional load placed by the new layer of shingles can lead to poor airflow in the attic. When excess heat and moisture builds up in your attic space, it’s only a matter of time before mold and rot make an appearance. If left unchecked, these can weaken the structural integrity of your roofing system. It doesn’t end there; since the additional shingle layer tends to absorb more heat from the sun, the newer materials are at risk of wearing out faster. 4. It nullifies your shingles warranty. Most warranties dictate that the new roofing system is installed with proper ventilation. Nailing new shingles over old shingle tiles doesn’t make that happen. Instead, it compromises the way air is circulated throughout the roof. HF Roofing does NOT installs new shingles on top of old & damaged shingles. Before installing your new roofing shingles, we make sure to tear off the old roofing system completely. This way, the new shingles will last you exactly what the manufacturer warranty says...