Well, I put a metal roof on my place... I put a skylight in the roof, too, so it's quite easy for me to inspect the roof and check out the heat or cold any time I want.

What I have found is that even on a cold winter day, there is a useful amount of heat on the face of the roof that is toward the sun. I do wish that I had put PEX under the roof for harvesting heat energy... it would have been easy and cheap and hidden from view and also hidden from environmental ravages.

Care would need to be taken to avoid nailing through the PEX, but it can be done.

The heat would be too low in temp to use directly for house heating, but it would be useful for DHW preheat.

Metal roofs have a much longer life than comp. This kind of plan would not make sense with comp, due to nails when a new comp roof goes over the old one.

-AC

For those of you with metal roofs, what's the sound like when it rains? It's obviously not irritating to any of you seeing as though you seem to love them. Is it loud when it rains compared to an asphalt roof?

Also, what about rain water collection? I've heard some people don't use gutters because they have metal roofs, but what if I want to keep collecting rain water?

I've heard that it is noisier but I'm not to worried about that as I like the sound of rain.. And I do plan on doing rain water collection when I get the roof finished

I am a musician and sound is quite important to me...

The rain-sound is going to depend on the type of metal you use and the gauge of metal and whether any sound damping material is placed under it.

I have light gauge aluminum roofing, with no serious damping material under it, over a cathedral ceiling. The sound is definitely louder than with comp. The sound is less like a pitter-patter of rain and more like a tink-tink-tink of rain... in that the sound of each individual drop is there to be heard.

Over the years, I have had comp, cedar shingles and now aluminum. As far as rainy day sound quality, my favorite by far is cedar. However, for durability purposes, I would not have a cedar roof again unless I could get old growth heart wood.

I have a metal roof and I have gutters to control moisture incursion into the cellar. Metal roofs are probably the best possible roofs for collecting rain water. Not to worry...

-AC

My new house has a metal roof. I don't notice any difference in the sound of rain, but that could have something to do with the 3 feet of insulation in the attic. The R-value is off the supplier's charts, but calculates to R-96.

We have R-50 of cellulose in the attic - so we get very little sound when it rains. If the windows are closed, I have to look outside to be sure that is raining for anything short of a downpour.

Metal roofs are great for water catchment. Virtually all the rain runs to the gutters and metal roofs are generally non-reactive to rainwater, so with minimal filtering / treatment the water is potable.

FWIW,
Tim

If you are in a hurricane zone, you can't have too many hold-down clips...

And you can do rain water collection with a metal roof, too. And/or laminated PV sheets as well.

My shop has a metal roof and I have many fir tree's. Gutters fill up fast.
Think about that. Sun dries the needle quickly and they slidedown the smooth roof. Not a problem just something to consider.
Snow is not bad in the Seattle area but I have been blocked in when all the snow slides off at once. :D

Years ago in a Yahoo group someone posted a message to see if there was a steel roofing profile that was friendly to being used in solar collectors. I replied that in Ontario Canada there is one steel roofing manufacture that has a profile that was almost perfect for solar collectors. Ideal Roofing has a profile called Security Rib that as 5/8 ribs that you put the screws in. The ribs are about 7" apart with the outside ones about an inch in from the edge. My only complaint about using it for both roofing and solar collectors is if it had double the number of ribs it could be put up as roofing at first putting screws in every second rib and then slowly converted over to solar collectors by lifting the panel and putting the pipes under the ribs not used with the screws and the glazing added over time. If it was going to be used for solar from the start the screws could always be put in the low part of the profile.

Having started my life in construction, taught Ind. Arts.-Voc-tech for 20+, & now a general contractor, done my own roofs, hse. etc.....one word of advise. On a 5/12 or greater pitch roof, even with sneaks, be very careful. I don't care how many guys are on the roof, each panel NEEDS 3-4 guys. DON'T get panels any longer than 18-20'. Even with all those guys you'll kink that metal, & ya' got nada. Don't forget the DOUBLE sealant, either, or you will not have a warranty.