[phxphun]

I'm getting estimates to replace the underlayment on my 3100sf clay tile roof. One roofer is planning on using 2-Ply SBS TU43. Another roofer has quoted a single layer of Fontana G-40 underlayment.

Are these two products comparable in quality and performance? Is one of these options better for the extreme Arizona heat?

 

[AndyWRS]

The two ply sbs TU43 would be my choice over a single layer of G40.

 

[stombaugh85]

I Is one of these options better for the extreme Arizona heat?

Why not go synthetic? or self adhering mod-bit sheets?

If you can only choose between the two felts then go with the 2-ply.

 

[phxphun]

Why not go synthetic? or self adhering mod-bit sheets?

Thanks for the opinion on the two options, stombaugh85.

I hadn't considered anything other than what the contractors had proposed, but I will look into the functional aspects of the products you mention.

Generally speaking, would the price difference between the 2-Ply SBS option and the synthetic or modified bituman sheets be significant?

 

[stombaugh85]

Thanks for the opinion on the two options, stombaugh85.

I hadn't considered anything other than what the contractors had proposed, but I will look into the functional aspects of the products you mention.

Generally speaking, would the price difference between the 2-Ply SBS option and the synthetic or modified bituman sheets be significant?

Ask your contractor. Prices vary upon regions. A good synthetic here is cheaper than a quality 2- ply felt.

 

[dDubya]

I'm not familiar with either product but I know that SBS commonly refers to modified bitumen. I install a self-adhered base sheet and cap sheet, which is SBS modified bitumen. Is that the two ply he is referring to? If so, it spanks the hell out of one layer of g40.

 

[tombeck]

We must be talking about a less than 4/12 pitch?