Sometimes homeowners will choose to save a few dollars on their roof by simply leaving the existing shingles on the roof and adding more over them. Don’t be that guy.
When trusses or rafters are engineered, they are specifically constructed for “x” amount of pounds per square foot, usually referred to as “Snow Load”. Here on the Northern Front Range of Colorado, the snow load is about 20 psf, pounds per square foot. (In the mountains the psf is much higher and calculated based on case studies.) This may seem low, however multiple layers of shingles add up really quick. A bundle of shingles is around 85 lbs and covers about 33 sqft. So that’s 2.5 pounds per foot, not including the sheathing (~2-3 lbs/sqft) or any other roofing material, vents and maybe even a swamp cooler too. Right off the bat that’s about 5 lbs per square foot, now add just 1″ of rain or ice to the roof at 5lbs per square foot and the roof has met the 10 psf. So by adding additional layers to the roof, the strength and reliability of the roof will be jeopardized putting the occupants inside in great danger.
So if a homeowner is in a situation where the roof needs replacing, Easton Homes LLC would highly recommend that it is stripped down to the sheathing and assessed before it is re-roofed. During the assessment, the quality of the sheathing will be evaluated and replaced if needed. This is a crucial step in the re-roofing process because homeowners rarely replace a roof because they don’t like the color. There is usually an issue with water damage/leaks or maybe wind damage. If something like that is covered up, then it is much more dangerous for the homeowners. Now there’s added weight on compromised materials, which can be a recipe for disaster.