Quarve Contracting
Thursday 19 May 2016

Common Question: Tear the Old Roof Off or Keep It On?

Posted by at 9:00 AM

As many homeowners in the Minneapolis area make the switch from conventional asphalt shingles to durable metal roofing, one questions repeatedly rises: “Should I tear the old roof off – or keep it on?”

09sep25h9a14That's a great question, but there is not a straight yes or no answer one way or the other.

Every roof must be inspected individually before coming to a final decision. That being said, it is very common to install a metal roof over an existing asphalt shingle roof, provided the integrity of the roof structure remains intact.  In fact, it's our recommended installation protocol whenever possible.

Here are some of the points that Quarve considers when determining whether to tear off or roof over the existing.

  • First of all, the roof must be in good condition, with no more than two layers of roofing installed previously. The best way to ensure “good condition” is to have a licensed roofing contractor get up on your roof and check for soft spots indicating a rotting or otherwise compromised roof structure. If your contractor has any question regarding the roofs integrity it should be torn off prior re-roofing.
  • Keep in mind that adding a layer of roofing will increase the total roof depth, which could interfere with things such as skylights and roof-top HVAC equipment. To avoid complications, you’ll want to discuss these aspects with your contractor before finalizing your decision.
  • Lastly, installing metal roofing on top of shingles requires that screws are long enough to extend through the roofing material and into the roof decking. If the installer in unable to verify a secure screw attachment due to shingle thickness, the removal of old roofing may be necessary.

If your roof meets the qualifications listed above, then roofing over the old material may be an excellent option for you. It’s a wise choice both monetarily and environmentally; you’ll avoid the expenses of roof tear off and disposal as well as lessening the load on landfills.

Quarve Contracting has been installing metal roofs here in the Twin Cities for over 30 years, and we have the experience necessary to provide you with a roof that will last you for decades to come. Contact us today for a free, no-obligation estimate.