Modified Bitumen v. EPDM Roof
Does anyone know the difference between a modified bitumen roof to a EPDM roof? I need to replace or maybe put a new layer on a brownstone in Carroll Gardens where I will be putting 2 HVAC package units on the roof. I have received one proposal for a modified bitumen roof, but an architect…
Does anyone know the difference between a modified bitumen roof to a EPDM roof? I need to replace or maybe put a new layer on a brownstone in Carroll Gardens where I will be putting 2 HVAC package units on the roof. I have received one proposal for a modified bitumen roof, but an architect is recommending an EPDM roof, but I don’t really know why. If the EPDM is better, does anyone recommend a contractor?
Go Kemper roofing. You’ll sleep better at night. I do.
Call Arek Kwapinski from City Skyline Inc. at 917.681.3255 He’ll give you a very frank assessment about what materials are good, better, best and he is very prompt as well.
EPDM is also generally though to last longer, which contributes to the green and cost factors. Properly installed, EPDM is better, IMO. EPDM is the roof of choice under wood decks, because repairing/replacing the roof requires removing the deck.
If you want to do rainwater harvesting, EPDM is way more better, as bitumen leaches petroleum products into the water, which isn’t great for plants.
You can’t lay the EPDM over the existing roof, so if you are interested in pursuing the option understand the cost may be a multiple of adding a layer of bitumen–ie. remove existing roofing, install a new smooth and properly sloped substrate (insulation can also be added at this point) and then the EPDM with all new flashings and connections to masonry.
I can’t recommend an installer–but you can find with through a manufacturer. I did the roof under my deck myself with some tips from the supply yard three years ago. That stuff is alot heavier than you would think.
exactly what arch66 said, but i will add that epdm roofing systems are generally more expensive. more installation / labor costs, and bc it’s a greener product.
A modified bitumen roof is a modern cousin of an old-fashioned tar roof. Plies of roofing material are set in a tar-like substance to create a membrane.
An EPDM roof is a single thermoplastic membrane adhered to roof substrates. If you get an EPDM membrane, it needs to be carefully installed, preferably by a manufacturer-certified installer, since an improper installation will leak. Remember, it is a single membrane. Modified bitumen membranes tend to be more durable and forgiving, since there are multiple plies. The bitumen itself also keeps water out.
Some people do not like to specify modified bitumen because it is a petroleum based product, and they think that you have to apply the bitumen using a 500 degree kettle. That used to be the case, (and it was really stinky, too, not to mention hazardous to keep a burning flame on the roof) but it isn’t the case anymore. There are modified bitumen formulations that are suitable for use on wood framed structures.
Some people also like EPDM because you can get it as a white membrane – and it is true – you should get a light colored roof because it will save energy, particularly if you are air conditioning your top floor.
Even though you didn’t ask, I recommend a modified bitumen roof. While it may be yucky to use petroleum products, a modified bitumen roof will do a better job of preventing water damage to your building than EPDM over the long term, and you can get a light colored cap sheet as well, to save energy.