About Cedar Roofs
1. The term “cedar” can actually refer to wood from a dozen or more different trees, grown all over the globe. Although red cedar has traditionally been the variety most commonly used to build roofs, recently white cedar has grown in popularity, due to its lower price and the fact that it is cut from new-growth trees.
2. Depending on individual taste, cedar may be cut in the form of either shingles, sawn on both sides, or shakes, which are hand split and re-sawn to result in a more rough-hewn, rugged texture.
Why They’re Eco-Friendly
3. Sustainable cedar roofs are environmentally friendly. Look for certification of sustainability by the Forest Stewardship Council.
4. Cedar roofs are durable. Normally warrantied for 20-25 years, they will generally last as long as 50-60 years or more if properly installed, maintained, and restored.
5. The lifespan of a cedar roof can easily be extended by replacing individual shingles and shakes that have warped, worn, or cracked. This saves the financial and environmental cost of installing a new roof.
6. At the end of their life, discarded cedar shakes or shingles are recyclable as mulch.
7. Cedar roofs are naturally weather resistant, standing up to great variations in temperature and freeze-thaw cycles. They are also earthquake resilient.
8. A cedar roof offers thermal resistance (a natural insulating effect) many times higher than that of other roofing materials such as aluminum. This saves energy by reducing the necessity for heating and cooling.
9. Cedar contains natural oils which resist mildew or decay and repel bugs. (Remember Grandma’s mothproof cedar chest?)
10. Cedar roofs are naturally beautiful, in a wide range of subtly varied colors and textures. They will acquire a distinctive silvery gray patina as they weather, allowing them to blend into their natural surroundings and look lovely on traditional or modern style homes, country cottages, or beach houses.
11. A cedar shake or shingle roof costs more than roofs made from many synthetic materials.
12. Because the wood needs to “breathe,” cedar roof installation must include a substrate that will permit air circulation.
13. Cedar roofs must be treated to make them fire retardant, using only products specifically okayed for cedar. There are green treatments on the market, though.
14. A cedar roof can be damaged by heavy snowfall and inadequate ventilation. It may be a good idea to use snow guards and a ridge venting system, depending on the specifications of your local building code.
15. You’ll need to be careful if you climb up on your roof to paint or perform other DIY tasks; the cedar is slippery when wet.
16. If you install a cedar roof, be prepared to provide ongoing maintenance. Fallen leaves and other debris should be removed twice a year, in spring and fall. This is not just for esthetic reasons — an excessive amount of debris will obstruct rain and melted snow from draining off your roof.
17. Cedar is a natural material, which provides a hospitable environment for growth of funguses, algae, and moss. Careful, gentle pressure washing approximately every 4 years will remove this growth without the use of harsh chemicals. About once in 15 years, restoration, including patching and replacement of the ridge cap, will be necessary.
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