Roofing ?: rubber vs metal

country_wife · #1 03/27/07, 10:01 PM

Our roof is flat on one part, and has a low pitch on the rest. We are shopping for a new roof right now. We've had 7 roofers here and none of them agree on anything!

Some say standing seam (metal) would be a good choice; others say it will leak. One said classic rib metal would work once he installs a small pitch to the flat part. Rubber was suggested by most of the roofers, but none of them can give me a straight answer as to how long it will last. One said 'forever'

(do I look like I was born yesterday??); a couple have said rubber will last 50+ years; one said it will only last 12 if we are lucky.

The pitched part of our roof is less than the ideal 3/12 pitch. We can't change the pitch of the whole roof without excessive construction due to the unique shape of our home.

Does anyone here have a flat roof? A rubber roof? A metal roof on a low pitch? Please share with me your experience: Does it leak? Is it difficult to maintain? Do guineas prance on your rubber roof? lol..they'd be all over ours!

sellis · #2 03/27/07, 10:12 PM

the house i bought had the same situation very little slop and yes it leaked like a cow peeing on a flat rock , it went everywhere . i did the roof in rubber and still am happy of course the ex has it know and is exstatic with it ...

rambler · #3 03/27/07, 10:17 PM

I really like metal roof on my buildings.

I have no experience with rubber roofs.

I think I'd look over the rubber roof real carefully, & lean to that for your specific needs.....

--->Paul

zukgod · #4 03/28/07, 01:50 AM

if your roof has little to no slope, rubber or torch down roof is the only option. Everything else Will leak.

foxtrapper · #5 03/28/07, 05:50 AM

The rubber like material used in roofing (it's generally not real rubber) varies tremendously. In quality, thickness, and exact material. Some last but a few years, some last for decades and perhaps centuries. It also varies with what you're doing on the roof. If you throw dance parties up there, it's not going to last as long as if it just sits there unmolested.

Metal roofs leak once the standing water goes over the nails and seams. You can play games with sealants, but it's all stop-gap measures. Metal's don't like being kept under standing water, and start to rust and corrode much more quickly than if the water simply runs off. Just look at the bottom of galvanized buckets to see what I mean.

Were it my roof, I'd be quite inclined to go with a membrane.

widfam · #6 03/28/07, 07:28 AM

I would recommend you look into a roof system by "Stevens". It is a rubber like product that you "heat weld" the seams together. It comes in white to help reflect the sun. Only certified contractors can install the product so you would have to find a contractor. You can look for one on www.stevensroofing.com. It is NOT a torch down system and I wouldn't recommend you use a torch down unless you find a roofer with a lot of insurance and a lot of experience. The stevens roof system will be more money but it will last much longer and be backed by the manufacturer because of using their contractors. It is used mostly in commercial buildings and a very tough product and when the seams are welded it makes one continuous membrane. I was a roofer in Pennsylvania for years and I would put this product on my own home. Good luck and remember price wether high or low doesn't make for quality work.....check references.

Weedologist · #7 03/28/07, 08:39 AM

Builders of underground houses have used rubber on flat roofs with great success. If your roof structure is strong enough you could even make it a green roof. Your guineas would love that!

Ford8N · #8 03/28/07, 08:44 AM

For a flat or slightly sloped roof go with rubber. As another poster stated, there are different grades and types. Silvercoat will make it last a lot longer and will cut your cooling costs a bit by reflecting heat. The coating will need to be done about every 5 years but the roof should last 20-30 years or more.

If the roof was pitched I would recommend metal.

Ohiogal · #9 03/28/07, 09:08 AM

If you can, change the angle of the roof. Its better in the long run and you can then install shingle or metal roofing. You may be able to do it by building a series of rafters with at least a 12/4 pitch over the existing roof. No more leaks.

country_wife · #10 03/28/07, 09:55 AM

I should also add that we live IN THE WOODS. There are critters on the roof on a regular basis..in addition to the guineas. Sticks, twigs, acorns, pinecones, leaves...all on the roof.

From what I'm hearing about rubber (we're looking at the .060 rubber), it can be torn fairly easily.

Does anyone actually HAVE a flat roof or low slope roof? What do you have on it??

The only pitch that we will be changing will be the flat part, but it will only be pitched enough to cause the water to run off.

country_wife · #11 03/28/07, 10:20 AM

Quote:

Originally Posted by rambler

I really like metal roof on my buildings.

I have no experience with rubber roofs.

I think I'd look over the rubber roof real carefully, & lean to that for your specific needs.....

--->Paul

What kind of slope do your buildings have (the ones with metal roofing)? Do they ever leak? Is snow an issue? Thanks!

The Paw · #12 03/28/07, 11:43 AM

Attached to my house is the town's old general store, which I use a shop. Ithas a very low-slope roof. It slopes about 2 feet over its lenght of about 45 feet. The previous owner used low-slope shingles and glued them down with asphalt cement. It has some leaks where water pools.

In my situation, I would look first at the standing seam metal roof, because I think with any pitch at all, that would work fine. It has been suggested to me that I should get it done in hot tar and gravel. I think that makes it a little less prone to damage than a rubber membrance.

If you are changing the pitch, I would think metal would be good.

vicker · #13 03/28/07, 01:38 PM

A standing seam metal roof will last longer then you and your children will live. A rubber roof won't, and if improperly installed will give you a very large headache (picture you roof with a large layer of rubber on in and one large air bubble between the rubber and the roof). If I had the option, I would not even think about it! A standing seam roof is the best there is and there ain't no better.

Highground · #14 03/28/07, 03:03 PM

We have a 12 x 16 covered patio with a rubber roof. It's the type used on travel trailers. Looks good, doesn't leak, should last many years.
Would I use it in your situation? NO-No-No

All those falling branches, cones, and birds will knock holes in it.

Wolf mom · #15 03/28/07, 03:53 PM

How about a foam roof?? It's sprayed on and during the spraying the sprayer can change the pitch. This happened to me in Phoenix with a flat roof so the roof would drain better.
After spraying on the foam, they spray an elastomeric type coating with sand particles in it. (I believe so birds don't peck at the foam.) It does need to be recoated periodically as straight foam does disintrgrate in the sunlight.
Many many roofs are done this way and have lasted for many years. Fireproof too.

Previously I had a heat-sealed rubber roof and the seam split. What a mess! Can only be walked on sporadically in socks as the rubber can puncture & void the warranty.

country_wife · #16 03/28/07, 10:53 PM

Does anyone know from experience how standing seam compares to classic ribbed metal?

vicker · #17 03/28/07, 11:27 PM

Yes, a ribbed metal roof is two pieces of metal that have ribs. When layed, the ribs overlap. Water could get through. In a standing seam roof, the joints are double or triple folded and soldered. With the finshed product you basically have a solid metal roof.

rambler · #18 03/28/07, 11:44 PM

Quote:

Originally Posted by country_wife

What kind of slope do your buildings have (the ones with metal roofing)? Do they ever leak? Is snow an issue? Thanks!

I have a flat porch roof that is a walk-out (can walk out the upstairs onto it). As well the top of the square house has a flat top 10x10 foot metal area. These are soldered metal roof. It is original to the 1926 house. They have held up well. Yes we have lots of snow, all winter here. As well we have 30+ inches of rain over sumer.

I would not expect today's metal & solder to hold up. Too flimsy & poor a materials in todays world.

The rest of the buildings are quite sloped, and are either metal or will be metal as the shingles peel off. Many of these buildings will have gone from wood to asphalt to now metal roof. One is used aluminum, the rest galvanised. One is original standing seam from the early 1920's.

Typical family farm here on the rolling hills/ prairie of southern Minnesota.

Anyhow, I think in today's world, a good membrane roof would be the way to go for a flat or near flat house roof.

Regular metal will have issues with the nail gaskets over time, more so with the flatness.

Standing seam needs the water to run off, if you have a flat roof & the snow piles over it & melts it can leak on the seams.

I don't think they do a 'seamless' metal roof with the lead & real good metal any more - don't have the materials.

That leaves a membrane. I haven't used one, but hear good things about them. Buy quality, skimping will cost you dearly. Don't waste your time & money on a cheap deal. You are starting with a big disadvantage - a flat roof. Someone skimped to start with. You got to anti up now to make up for it.

--->Paul

foxtrapper · #19 03/29/07, 06:33 AM

Living in the woods with critters on the roof does change things. Doesn't mean a rubber roof is unsuitable, but a cheap thin one is. Remember, pond installers use rubber liners meant to survive sharp rocks and claws without damage. Roof accordingly.

I have a flat roof over the large dormer a previous owner built on the house. Covered with rolled roofing, sealed with care by yours truly. Includes two raised skylites, home built. Roofing material is rolled up on the side of them, and carefully sealed. It's a urethane type sealer I used on the seams. It's worked well... so long as I stay active on the maintenance. Rolled roofing on a flat roof is not a recommended way to go.

I've had standing seam and the newer corregated type metal roofing. Standing seam is overblown, mostly from owners, who have to justify the expense. It's labor intensive to install, any coating is fractured on the seams when bent. You tack down tabs, roll the metal roofings edges up in those tabs, and that's all that holds it in place. When standing water gets up to the top of the seams, it leaks. Snow does a dandy job of helping this. When wind gets under a standing seam roof, it all peels off and blows away. Every severe storm has some barn with a standing seam roof around here newly roofless.

Corregated steel is much easier to install, essentially a DIY job. When the water gets up to the nails, it leaks. Because you're driving nails in to the top of the rib, the rib flexes under the nail, and it cannot seal perfectly. These roofs are prone to wiggling the nails up as the panel flexes and vibrates in the wind. These are the metal roofs that have individual sections ripped off in wind storms. Plenty of this damage around here as well.

Of the two, I prefer standing seam.

Junkmanme · #20 03/29/07, 07:38 AM

Having grown up in a "flat-roofed" building, and seeing it repaired almost yearly (with very short term effectiveness, I must add), I am TOTALLY against flat roofs!

I would spend the extra money required to put some more and then some more "slope" to the roof BEFORE I WOULD EVER ATTEMPT TO REPAIR IT!

Get some slope...then...fix the roof!

Flat Roofs LEAK !!!

just my (experienced) opinion and total conviction!
Bruce