Take a trip to your attic. Can you see light coming in from the outside? Are there signs of water damage? Look for spots where the roof deck might be sagging. If you have a slate roof, look for signs of powdering.
Refrain from walking on your roof, especially those with a steep slope or if it is made with tile or slate. Simply hop up on a ladder to check it out. Make sure to also view your entire roof from a distance – if there is a lot of damage to single area, it is likely an architectural problem, not a roofing one.
High time for a roof replacement | @ iStockphoto.com / Mediaonela
When to Replace an Asphalt Roof?
- after 15 - 20 years, depending on the type
The main thing to look for with asphalt roofing is granule loss. Loose or missing shingles, curling edges or rot are also clear signs that roof replacement is near. Moss growth will shorten the lifespan of your roof, but it doesn’t necessarily indicate roof replacement. Clean it off to assess the shingles beneath. Algae growth, although unsightly, does not damage your roofing as it does not have a root system like moss.
When to Replace a Wooden Roof?
- after 15 - 30 years
Wood roofing is highly variable due to the type of wood used, the thickness of cut and your climate. A few broken or missing shingles can likely be repaired, but you should look for more serious signs such as cracks developing on the edges of shingles, signs of rot or mold, graying colors indicating micro-fungal growth, damage from pests, and moss or plant life.
When to Replace a Tile Roof?
- after 50 - 100 years
Clay tile roofing is very durable, yet also very fragile and likely to break if walked on. Poorly installed tiles are susceptible to slippage. As with wooden or asphalt shingles, singular tiles can be repaired by a qualified contractor. However, if 10 – 20% of your tiles are cracked or broken, it might be time for a do over.
Curling shingles on asphalt roofing | @ iStockphoto.com / mgvAn
When to Replace a Fiberglass Roof?
- after 30 years
Over time, UV rays will degrade the material, leaving it looking dull and susceptible to cracking. A hail storm can leave pockmarks, and a feisty round of fireworks on Independence Day landing on your roof can also reduce its lifetime.
When to Replace a Metal Roof?
- after 30 - 100 years, depending on the material
The rust proof coating can degrade over time on metal roofing, and should be maintained. Extensive rust damage can indicate roof replacement, as well as holes, tears and cracks.
When to Replace a Slate Roof?
- after 45 - 75 years
Slate roofing is rarely subject to an entire roof replacement. An annual inspection is prudent, as repairing small defects such as broken tiles or loose fastenings will ensure a long lasting roof. Two major signs of imminent roofing replacement are powdering on the underside and major delamination or flaking. Try the “knuckle test”: tap the slate at several different places. It should emit a clear, solid sound. If you hear a dull thud, roof replacement is in order.
When to Replace a Rubber Roof?
- after 30 years
As with other flexible flat top roofing systems such as bitumen, the main problem with rubber roofing is trapped moisture, often from loose flashing or cracks. This is most easily seen in the summertime, as the water will heat up and create bubbles on your roof.
Contact a Qualified Roofer
If your roof is nearing the end of its life, contact a qualified contractor sooner rather than later. When you are literally dealing with the roof over your head, it is better to catch the problems before you have a swimming pool in your living room.