But basically if its not causing a problem dont do anything depending on what roofing material is on the roof.
Roof felt lifespan.
A built up roof bur is a layered roof that is created by alternating layers of roofing felt and waterproof materials such as fiberglass and hot tar bitumen.
When it comes to a felt flat roof s lifespan the majority of guarantees will only last for ten years.
It typically has a lifespan of 40 to 50 years although most manufacturer warranties only guarantee a lifespan of 10 to 15 years.
Thermoplastic olefin membrane is another flat roof option made.
Metal 30 to 45 years.
Below you ll find the average of each of the most commonly used materials.
Gereral recomendation is to replace the underfelt every 20 25yrs.
Normally used on roofs that are flat or with a very slight pitch bur roofit is fire resistant and inexpensive but the roofing is messy and smelly to install.
Felt is a traditionally used material on many flat roofs.
Although your shingles are your roof s first line of defense against the elements having a backup layer of weather protection underneath helps extend the life of your roof deck.
A lack of maintenance.
Despite no authoritative answer on the life of the system there are many spf roofing systems that when coated and maintained properly have lasted 50 years giving spf the longest roofing system lifespan of all common roofing materials.
If well installed and maintained roofing felt could last longer but it will require time and money to keep it in a decent state.
Asphalt shingles architectural.
And in the event of a major weather event that breaks your shingles loose the roofing felt guards your wood deck against rain and water until the shingles can be.
The most obvious factor that affects the lifespan of an asphalt roof is a lack of regular maintenance and upkeep.
A high pitched roof can more easily allow water and debris to run off which typically means the roof will dry out much more quickly.
More importantly the lifespan of a shingle roof is greatly affected by the overall materials used.
Asphalt shingles 3 tab.
15 to 18 years.
Concrete is a much more durable roofing material with a life expectancy of 35 50 years.
Slate depending on the quaility 35 100 yrs.
24 to 30 years.