On occasion, a client will call EKAN to only inspect the roof on their property. This limited inspection provides an estimate of the remaining service life that can be expected.
Roofs are expensive to replace and homeowners should use all available resources to make a judgement when replacement is necessary. Obviously a leaky roof with water stains on ceilings and walls are obvious give-away signs that the roof is in distress. But what about a roof that has been trouble-free to date on an older house?
ROOF MATERIAL LIFE EXPECTANCY
As a start, consider the following average service life for various roofing material:
- 15-20 years for 3-tab shingles
- 15-20 years modified bitumen (torch-on)
- 15-30 years EPDM (rubber)
- 20-30 years for architectural (laminate, layered type) shingles
- 25-30 years for wood shingles
- 30-40 years for wood shakes
- 30-40 years for metal roofs
- 40-50 years for concrete tiles
- 50+ years for slate, copper, tile
FACTORS INFLUENCING ROOF LIFE
The actual life expectancy is typically less due to site conditions. Organic growth, tree branches touching the surface, dark roof colours, roof orientation to sun, expansion and contraction due to weather extremes, low slope, poor attic insulation, inadequate attic ventilation, wind uplift, product quality, installation workmanship… all factor into remaining roof life.
Now back to our client’s inspection call for an opinion. In their case their roof type was a 3-tab shingle. The roof was original to the house, which was built almost 30 years ago. An inspection of the roof identified all the usual suspects of old age: tile shrinkage, warping and loss of the protective granular cover. The granules protect the asphalt and fibreglass base material from UV degradation.
An inspection of the attic determined that there was no evidence of leakage, except for one location. At that location there was substantial discoloration of the sheathing. However it was suspiciously directly above the exhaust vent from the kitchen. The kitchen range hood may have been vented directly into the attic, and at some point in the past, the vent could have been extended through the exterior gable end wall. In any event, the sheathing tested dry with a moisture meter. Not surprising with our drought conditions. The only way to determine if there is an active roof leak will be to return during our fall rains and test again for leakage… and we agreed to do this.
In conclusion, the inspection results were that the roof had well exceeded its life expectancy. With the exception of one suspect location, the roof was still performing well. Other than a follow-up inspection during the rainy season, no immediate action was recommended. However the client was informed that they should budget for a new roof within the next 2 years and to make use of that time to search, short-list qualified contractors and receive competitive quotes.
A most important consideration in comparing bids will be to review the contractors’ warranty periods as they may vary considerably from 2 to 10 years.