I think there may be better options for almost flat roofs.

my parents had an 'almost-flat' roof for many years - I know roofing products have changed much of the years - if you are going to have an 'almost flat roof', then make certain your roofing materials are the best you can afford THAT WILL KEEP THE WATER OUT OF YOUR HOME.

I have this - essentially:

http://www.mbci.com/products/insulated-metal-panels/insulated-roof-panels/cfr/

which this company also has this:

http://www.mbci.com/products/roof/exposed-fastening-roof-panels/pbr/

Rated down as low as 1/2:12 slope. We have 1:12. Single slope / shed roof. NO ISSUES and I would bet we have significantly more rainfall than you do.

I think the keys to using this type of material are:

1. A simple design
2. A commercial installer

Our panels / materials costs were expensive - and honestly - I can't see a quality installation on this overall type of roofing being any less than a more traditional residential standing seam. In order to do it, you need a good commercial product and one that requires a lot of detail and "accessories" installing it. Flashing, finishing, hiding the edge - it's kinda an art to do this well - labor intensive.

But - it also works and is designed to work at these low pitches.

just_janni,

The second product you linked is what I have been looking at. Specs wise it looks like a great match. I see pics with standing seam roofs, but it is hard to find pics of homes using PBR. As you said, we do not get a lot of rain. My roof should be pretty simple, basically two shed roofs perpendicular to each other with one elevated over the other.

I am wondering how I might find a good manufacturer or installer in southern California. Googling gives me a bunch of links, but I do not know how good they might be. Metal roofs do not seem to be popular around here. When I mentioned metal roof to my architect and GC, they are only familiar with standing seam, so I am doing the leg work myself as standing seam is not in the budget. Thanks for your insight!

I was fortunate that a friend of a friend owned a commercial roofing company and did an amazing job for us. I would call around and get references - smaller, locally owned commercial companies might be the best - or - at least people who have worked specifically with the product and then go see the installations. Also - it will be interesting if they will do a smaller, residential job. And - do ask for VERY detailed drawings on how they will finish - I can try to find mine and post. Again - the detailing required to finish this off nicely is extensive.

If "PBR" stands for Pabst Blue Ribbon, you're in trouble.

Mark, perhaps I do not quite understand your humor. As far as I know, PBR is a standard type of metal roof panel. Lots of manufacturers make it. I am just trying to find a good manufacturer and installer.

You are asking for trouble once you get into the 1's range of pitch unless you are going with a mechanical standing seam.

With a flat roof, the classic 3- or 4-ply built up roof will work perfectly and save you a ton of money compared to a metal roof and the special installation techniques which will be required. Forget metal if your pitch is less than 4 in 12.

We put metal on flat roofs all the time. Almost nobody in our are does BUR because of the fire hazards and lack of qualified personnel to work on them. In areas like Florida and California, they may be more popular and you might still see tar kettles around, but not around these parts.

Combine that with the fact that metal, when done right, is basically permanent (in addition to being more efficient and environmentally friendly), its a better option for some folks.

And what would you say is the cost comparison between a built-up roof and a metal one for a flat roof?

Given the fact that BUR is almost non-existent here, metal is more cost effective on the initial cost and therefore much less costly when you figure the life cycle costs.

Where is the "dodge"? I guess you missed the statement above where I said: "metal is more cost effective on the initial".

That would effectively establish a cost comparison that metal is, in most cases around here, LESS than BUR.

Most of the flat roofs around here are single ply membrane systems vs. anything on the BUR side of things. Easier to do, last as long when done right, and don't require heat or flammables.

It's a very simple thing to simply give the installation costs of built-up roofing, single ply roofing and metal roofing. Since you're in the business of selling metal windows, why don't you share with us the installation cost of metal roofing with other commonly installed roofing systems for flat roofs. Don't hide behind "cost effective" mumbo jumbo. What are the comparable installation costs?

Look...I don't care what sort of roofing the OP decides to install. But, I do think it's fair to point out the cost disparity among the various roofing systems for flat roofs.

For the OP, Google "roofing systems for flat roofs", scroll down through all the advertising and so-called "reference posts" from who know whom, and go to the Wiki posting. Read and decide.

Actually, it is anything but simple to post a price about something without it being potentially undependable information. You do understand the very basic concept that the cost of doing business (labor, overhead, legal, etc.) is different from region to region. That would be like asking what a 3 bedroom rambler costs. If someone commented on that without a bunch more information at hand, it would be...in a word...idiotic.

How much does that 3 bedroom rambler cost in Central Oklahoma vs. San Francisco.

You asked and I have long since answered that in our marketplace, there is little to zero BUR and most folks are larger commercial applications are running single ply membranes. Very few folks use anything that requires open flames (torch modified) or a tar kettle. As a matter or observation, I don't know when the last time I saw a tar kettle up here. That said, I was down in Florida to see some family a few months back and DID see a tar kettle so I fully acknowledge that it is still used as a roofing system in this application. BUR is also a fantastic option in many cases because of its adaptability and re-coat option. It just isn't popular up here.

If you want to keep answering price questions from halfway across the country with zero background on the region of the specifics, by all means, go ahead. The internet is full of "experts". For our region, the spread between single ply and other flat roofing systems, and metal, is little to none depending on who is quoting it.

Hope that the OP didn't get lost in all of our back and forth.

I would only put a metal roof at the minimum slope required by manufacturer on a simple shaped roof: no valleys, dormers, funny transitions, etc. I was not aware that any exposed fastener roof was offered to go as low as 1.5/12. If you go that route, have the roofer install a substantial underlayment. Many roofs here are installed with a full peel and stick underlayment, partly due to ice and snow issues (which you don't have) and partly to have a waterproof secondary membrane under the metal roof, should there be leaks or condensation.

Just so the record is clear, I did not recommend an exposed fastener roof on anything at that low a pitch. You can, however, easily run a mechanical standing seam at those type (i.e. low) pitches very easily.

Virgil, I am not sure how the wiki page helps me. I have already read about the different flat roof systems. Bascially, I am looking either at membrane or metal roof. I would prefer metal. Of the metal options, I would like to use PBR. My question deals with PBR which is designed for a nearly flat roof. I am trying to find out if people have had any experiences with PBR to share.

LC, as long as you have fully investigated the applicability and cost implications you are in a good position to make an informed decision. Good luck!