Flat roof-rubber rolled vs hot tar

I am having a neroof installed and want to get an opinion on which method is best and how they compare cost wise. The roof is flat and about 20 years old. I have been told it can be roofed over. I plan to move in the next 2 or 3 years so why do a tear off. Some have suggested a rolled rubber roof and others say that the old hot asphalt roof is still the better method. I live in the Chicago area and we have cold winters and hot summers. Thanks for any suggestions. Also is one method more expensive then the other.

both are good if done right. Some situations will favor one over the other. If you have a BUR now they can somtimes scratch it and then apply another hot roof right over it.


If your reason for not tearing off the roof is to screw the person you sell your house to. That is a bad reason.

It depends on the condition of the existing roof if you can roof over.

if its not leaking then clean it off and coat it.

otherwise tear it off.
put a good torchdown or hot tar bur.

good luck.


are you in the city or the burbs???

Personally, I’m always of the opinion that it’s a 'best practice" to go to bare wood / deck surface so a thorough inspection can be done.

I also agree with Ed; if your primary reason for doing a cover over without tear-off is because you intend to unload the property in the next 2 to 3 years, that’s 100% NOT the reason to pass on doing a tear-off with re-roof (aka a roof over only).

If anything, it may cost you MORE or hinder your ability to sell the property because a good roof inspector (whether real estate ‘generalist’ or knowledgeable roofer) might spot a 2 layer job & advise to NOT purchase based on:

  1. The potential for hidden damage beneath the un removed layer
  2. The potential for damage due to a 2nd layer roof which adds extra weight
  3. The potential for extra costs should the new owner desire to affect repairs or do a full re-roofing.

& That’s my take on it.


Roofboss is asking because there are laws in place for the type of roofs you can use in Chicago.

You must reach a certian reflectivity level. To counter the “Heat Island Effect”.