Low Slope Roof - Conflict

I had someone come out and take a look at my porch roof which I intended to replace in a couple weeks. My gut is telling me what is being proposed will not last. The contractor proposed a 2 ply gaf system whereas my dad is saying torch down. I want to bring others out to provide more estimates but wanted to seek out unbiased professional guidance as to the proper way to fix it.

I have researched Flintlastic Base 20T and GTA as a possible solution, Polyglass’s Polyflex G as a back up, and IB Roofing Systems which is my least favorite option because of the overall look. Picture is included below and thank you in advance.

The IB PVC will last the longest and you should be able to get it with a shingle pattern on it.

This will be the best and likely the most expensive option.

I don’t like the self adhered modifieds for several reasons but a couple are that they lose their granules very quickly and they are extremely expensive for what they are and compared to better solutions.

My experience with Polyglass SA Reflex resulted in a warranty claim within 2yrs of application. Every granule on the roof was in piles at the drains. I think they discontinued it, but I’m not a fan.

Ok thank you both. If I understand, the granules while they look appealing are not worth the hassle or added expense.

Axiom - do you mind sharing what better solutions you believe will be more suitable? Thx

EPDM (rubber), Torch applied APP modified bitumen, PVC, are all much better than self adhered modified.

Granuels are for UV protection.

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I understand granules have a purpose other than appearance (appearance was the main reason why I was considering them so they could match the roof) but if trade professionals with more experience than I will ever have in 20 lifetimes say that eventually the granules fall off (less than 3 years in 1 case) it’s a lose/lose situation and poor investment on my part - at least I think. Maybe I need to consider colored caps without granules but appreciate the feedback.

I would use flintastic base or yossemity base, one ply of sta smooth torch applied, set a metal flange on top of the smooth in roof cement along the wall and mechanically fasten, set peremiter edge in cement and mechanically fasten, prime all metal, and finish with a layer of GTA.

There should be no roofing cement on the roof at all
When you break out your torch.
Roofing cement catches fire the second the torch hits it and the two materials do not mix/ cure together.

You dont cement the perimeter before you install the metal drip edge.
You install a starter strip using the same material turned upside down.
If installing 2 layers, the starter strip is not necessary.

I wouldnt suggest 2 plys of torch on such a steep roof,
There is really no need for it.

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Thank you. Is there a 2 layer torch app modified bitumen that I should gravitate towards other than the flintlastic?

We use all certainteed, torch down is all in the details and a quality install. Everyone does things a little different, but installed properly and with good slope we have 3 ply modified roofs out there well over 30yrs old.

Much appreciated - thx again

Why single ply system at all, composition roof go’s down to 2/12 pitch.

My understanding there is nothing to nail into. I believe it’s a tin or some other type of metal roofing