Q & A - Should I Tear My Roof Off?

Is it better to roof over my existing roof or tear the roof off?

It’s that time of year again when re-roofing is on the mind of many people. When thinking about doing an asphalt roof job, some people think they can save a few bucks by roofing over the old roof vs tearing the roof off.

In some areas, two roofs are acceptable, with some limits of roof types. Is it a good or bad thing to do? Should I tear my roof off? What about the extra weight on the roof? The roof, if left on and covered over with a new roof, will never have the sheathing exposed and any unseen dry rot could go un-repaired for another roof life. I think this is the main reason I advise removing a roof, now an inspection can be made and the dry rot can be fixed. Dry rot can be repaired much easier with a torn-off roof than if the old roof is left on.

The cost of removing a roof is not as much as you may think.

Having the roof left on and then repairing the dry rot later is very time-consuming and means costly dollars spent later. As seen in this photo, the dry rotten barge rafters and overhang boards can be replaced while the roof is off much easier than with a roof on. Some will say, I can just remove the roofing in the bad areas I can see from underneath the roof sheathing. This is true, but you will never see all of the damaged wood or the early stages of mold, mildew and dry rotting wood fibers from looking at the bottom side of the roof sheathing. It is just a better job in the long run to do a tear-off.

Here repairs are made on damaged plywood that seem to occur in transition areas like this. Having the roof removed and doing both a low slope roof and a steep slope roof at the same time gives you the best results.

Have a question? AskARoofer.

Find your local roofing contractor in the RoofersCoffeeShop® Contractor Directory.