Roofing recommendation

[Robert Jones]

Ok guy's, so we have an offer in on a home that has a low slope roof with rolled roofing installed. No gravel, just sheets of comp. Have any of you owned a home with a flat roof and used a different(better) product? Thinking either pvc or tpo...I went up on the roof and in the area of the water runoff/downspouts, the granules are just falling off like crazy. Also, how about a decent way to protect the downspouts on a low slope roof? Pine needles are the main issue for blockage in my area.

Thanks

[hausdok]

I propose a little thingy that looks like a micro masceration grinder and fits in the downspout inlet. Water runs through it; no problem but when a solid object enters it starts spinning and grinds the material up into pancake flour. Viola! No more clogged downspouts.

Seriously, I think you'll just need to climb up on that roof at least once a month and clear 'em.

Are you sure it's mineral surfaced roll roofing and isn't a modbit membrane with a coating of stone granules?

ONE TEAM - ONE FIGHT!!!

Mike

[kurt]

There's probably more low slope in Chicago than pitched. No reason for problems with flat roofing.

I'm a huge fan of APP mod bit. Any of the systems will work, but APP allows one a little more "freedom" in making repairs or alterations. For one thing, you don't need a hot air welder; a simple torch works fine. It's also a heck of a lot cheaper than TPO or PVC.

I'm with Mike; are you sure it's not granulated mod bit?

[John Kogel]

Roll roofing = exposed nails sometimes gooped with tar

Mod Bit (torch-on) = no nails and at least 15 years no trouble.

Mike is right about the needles.

Screens don't work, or they work too well.

My neighbors on three side have old growth Sitka Spruce trees that shed needles like a XXX sheds XXX. On my low slope, 2 in 12 roof, I got rid of the needle catchers and ran my downspouts into a buried 4" drain pipe that runs out to the ditch along the road. Goodbye needles.

[Robert Jones]

You know guys, I think it is granulated mod bit. No exposed nails, so has to be torched at the seams.

[hausdok]

You know guys, I think it is granulated mod bit. No exposed nails, so has to be torched at the seams.

Then,

Assuming they properly detailed it where the downspouts are connected to the gutters (If it has built-in gutters) and there are proper cant strips and copings and flashings with care you should be able to get at least 15 years from installation. You'll still need to get up there to remove all of the needles a couple of times a month.

ONE TEAM - ONE FIGHT!!!

Mike

[Tom Raymond]

15 years seems like an awfully short service life for such a large and expensive building component. Factor in the material price volatility and it would be a major consideration for me.

[Steven Hockstein]

Flat roofs usually = more maintenance and more chance of leaks. Is it a modern house that includes a low pitched roof as part of the design? Would it make sense to alter the roof lines the next time you need a roof so you can install shingles? Any photos?

[kurt]

I don't know fellas.....

Granulated mod bit around here is 25 or 30 years, easy. I don't know where people are getting the 15 year thing. I look at thousands; it's hard to mess them up. You want .032 or 28 gauge steel; aluminum doesn't work.

Do that, it lasts.

[Jim Katen]

I don't know fellas.....

Granulated mod bit around here is 25 or 30 years, easy. I don't know where people are getting the 15 year thing. I look at thousands; it's hard to mess them up. You want .032 or 28 gauge steel; aluminum doesn't work.

Do that, it lasts.

In my area, the thing that gets granule-covered mod bit is decaying fir needles. If the thing stays clean, yes, 25 or 30 years shouldn't be a problem. But if it gets covered with a matt of decaying needles, the decay process seems to just eat up the bitumen as if someone poured acid on it.

[hausdok]

I don't know fellas.....

Granulated mod bit around here is 25 or 30 years, easy. I don't know where people are getting the 15 year thing. I look at thousands; it's hard to mess them up. You want .032 or 28 gauge steel; aluminum doesn't work.

Do that, it lasts.

In my area, the thing that gets granule-covered mod bit is decaying fir needles. If the thing stays clean, yes, 25 or 30 years shouldn't be a problem. But if it gets covered with a matt of decaying needles, the decay process seems to just eat up the bitumen as if someone poured acid on it.

Hi,

Yeah, it is acid - tannic acid to be exact. Wet tree debris is full of the stuff and it causes the bitumen to start hardening and makes the granules slough off - that's why I give 'em about fifteen years around here.

Robert will probably go up there and get all of that crud off the roof on a regular basis but the average homeowner around here doesn't seem to go up on the roof to clear that stuff until the downspouts are so packed with needles that when they freeze they split the downspouts wide open or when the built-in gutters start overflowing onto the face of the fascia and cascading down on the main entry or deck. Then they suddenly get interested.

Down in the city where there are very few trees tall enough to dump a ton of needles on top of those flat roofs, no problem, they seem to look new after ten to fifteen years.

ONE TEAM - ONE FIGHT!!!

Mike

[John Kogel]

Robert, good luck with your purchase. I'd rather have a low-slope roof than one that's too steep to climb.

[Robert Jones]

Thanks for the input guys. The people we are trying to purchase the home from haven't stayed on top of the exterior of the home in some time. It is a short sale so I think they mentally checked out a while back. The entire interior of the home was taken to stud in 2007-08, re-wired, re-plumbed etc... Since we put the offer in, I have gone over there twice(vacant) to clear the downspouts. I pulled out the "cage" type apparatus they had in the openings to try and let it drain a bit better. What about increasing the size of the downspout to say a 3"? Worth the hassle?

[Bill Kibbel]

My last house had one of the additions under some mature cedar trees. I put a "funnel" downspout outlet on the gutter and it never clogged again.