My roof has several layers of asphalt shingles. Can an additional layer of shingles be added over top?
It is not uncommon to find several layers of asphalt composite shingles installed over one another. However, the number of layers should be limited to two.
Benefits of Removing Used Roofing Materials:
- Stripping used shingles allows your roofing contractor the opportunity to inspect the roof deck and if required, to repair damaged areas.
- Installing new asphalt shingles over older materials may reduce the life of the new shingles and depending on the manufacturer, may reduce or eliminate the product warranty (i.e. by trapping water between old and new shingles).
- The weight of a roof system will be reduced. For every 100 square feet of roof, several hundred pounds of roofing material per layer is required.
- The cost of labour to remove materials and the cost to dispose of the waste will likely increase in the future.
- Improving items, such as the eaves protection, flashings and ventilation system become easier.
Visit the home inspection experts at AmeriSpec of Canada for more tips and valuable home improvement information.