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Because most metal roofs have some real thickness or depth to them, you will want a skylight that sits up on a curb of at least 6". In many cases, the flashing kits provided with the skylights can work with metal roofing. Obviously, uphill flashings stay on top of downhill flashings. On the sides of the skylight, some products will be butted against the flashing and sealed (with a hidden water barrier flahing beneath it all) while other metal roofing products can actually be locked into the flashing. Consult with the manufacturer of the metal roofing product you choose in order to get detailed instructions. Todd Miller
Todd Miller
Isaiah Industries, Inc.

6/10/2001
does anyone have any written information about use of plastic-disk headed tarpaper nails under galvalume roofing???
Guest User

6/28/2001
In April 1999, we had a metal roof installed. Our original roof was stripped down to its 10"w plank boards. We absolutely love it. Last fall, we developed a large leak and several small leaks. The contractor appeared to repair the large leak until we had a very windy thunderstorm last week. Rain water poured down an outside wall. He has not returned our call yet. He also could not find were the locations were for the small leaks. I have heard a rubber sheath should be placed on the roof boards prior to metal panel installation, is this so? Would that stop the leaks? Thank you
Guest User

7/19/2001
Our house was built 10 years ago and at first the leaking was minimal. Now it is pretty bad and no one seems to know the answer. It is worse during the windy rainstorms. Also, I wanted to add about skylights on metal roofing. The ones we had originally installed were 6" above and came down the second year with the snow, since snow really slides fast off metal. We had to have them specially altered to be flat, and they leak a little most of the time. If I had it to do over again, I would not use a metal roof. If anyone has any answers to these problems, it would certainly be appreciated.
Guest User

7/19/2001
Unfortunately Chris you have not provided enough information to offer an opinion. One needs to know 1)the type of material installed 2)the type of fastening method 3)Roof slope and length of rafters 4)Roof configuration (Valleys, gables, hips etc) 5)number and type of roof penetrations Common types of problems are a long steep roof intersecting with a low pitched roof such as a dormer. Here the water picks up speed coming off the long roof and can run up under the otherat a valley if a "W" valley metal was not used. An ice and water membrane installed under the valley will protect in this case. Please email the details directly and I will attempt to provide an answer.
Guest User

7/20/2001
I can appreciate your frustration as a leak is the last thing anyone expects in a new roof especially in a new home. It is impossible to get water to leak through a sheet of steel so the first place to look is to ensure that all the joints in the sheets are laid tight. As the leak seems to have slowly matured it is probably at flashing location and probably related to a sealant failure. It takes a new wood framed home about 3 years to dry out and settle in and depending on the style of the home you may have a differential movement as between a fist floor roof and a second floor wall or a brick chimney especially two floors. I would look here first. As to installing skylights,in a house with a metal roof in snow areas, it is best to use a curb mounted light. The self flashed lights meant for asphalt shingle installation will fail in haevy snows. Additionally one should keep the light as high up the roof as possible and install a snow defector just above it which could easily be installed in you situation. If you would provide more information on the roof configuration I would be pleased to discuss your problems in more detail.
Guest User

7/20/2001
Provided you have a properly constructed and ventilated roof assembly, installing the vertical rib steel direct to the deck is acceptable provided the deck is in good condition. Most building codes require a minimum 30 lb underlayment which will help stop any telegraphing through the steel. Furring the roof however does have some additional benefits. It will allow you to level the roof out if required, provide a proper substrate to anchor the roof for wind uplift and reduce heat transfer to the attic.
Guest User

7/20/2001
I would like to install a metal roof on my house even though i am not a pro i have installed many asphalt roofs. Is a metal roof installation something that requires special skills to install? would you consider it a DIY project?
Guest User

7/21/2001
I am unaware of any studies into the use of plastic cap nails beneath galvalume. However, I have seen these nails used extensively beneath various metal roofs and I have never known of any problems. Generally, the steel nail drives in deeply enough that it doesn't contact the underside of the metal roof panel. With some thinner metals, though, there is some risk that, by walking on the metal panel on top of the plastic disk, it might imprint the metal a bit. If you have any specific concerns you'd like us to research, let us know. Todd Miller
Todd Miller
Isaiah Industries, Inc.

7/21/2001
As you've seen on the MRA website, metal roofing is available in many styles. Some styles require greater installation skill than others. Also, a lot depends upon the complexity of the roof being covered. Some metal roofing panels are available to the public through lumberyards and home centers. Some metal roofs, however, are available only through experienced installers. I'd suggest using the MRA website to choose the type of metal roof you're interested in and then contacting the manufacturer(s) of that type of product and inquiring as to what distribution channels they have. Todd Miller
Todd Miller
Isaiah Industries, Inc.

7/21/2001
I am searching for proper installation procedures for metal/steel roofing. I recently completed contruction of log home w/steel roofing. Recently I was told that it appeared that the contractor installed roofing system incorrectly. Where do I get information re: installation procedures.
Guest User

8/6/2001
If at all possible, try to track down the manufacturer of the product that is installed on your home. Different metal roofing profiles have various nuances in installation and the product manufacturer should be consulted as the leading authority on proper installation. If you cannot track down the manufacturer, please provide us with as much information as possible as to the roofing profile, product name, etc. and we will help the best we can. Todd Miller
Todd Miller
Isaiah Industries, Inc.

8/6/2001
Hi I live in Northern N.J (Flanders) Could you provide me with the name and location of the nearest supplier of metal roofing. Question #2. I have 2 skylights on the roof is their special - flashing kit to dress these for metal roof. Thank You very much
Guest User

8/8/2001
We have a double wide modular home. It only has the one shingled roof which is leaking. We would like to put a metal roof over the shingles. We were told to put tar paper down first, then the metal. Is this correct? Also, we would like so instructions on how to put the roof on. Thank You, Brenda Bess
Guest User

9/23/2001
You should probably check the pitch of your roof as that might somewhat dictate what type of metal roofing you choose. Pitch is referred to in the relationship of rise over run. For example, a 3:12 pitch refers to a roof that rises at least 3' for every 12' you go back horizontally. This is the minimum pitch for many of the horizontally-run shingle, shake and tile profile products. If your roof pitch is less than that, you need to look at a vertically run metal roof panels that are suitable for lower pithes. Most metal roofs do specify new underlayment. Even when going over an old roof, underlayment helps provide a better work surface as well as additional protection during the installation process. It also helps to protect against the occasional condensation that might form on the back of metal roofing during certain wewather conditions. Some metal roofs that lay very close to the roof deck will require the use of a "slip sheet" on top of the underlayment, such as red rosin paper. There are also some polyethylene underlayment products that serve this purpose. Basically, the slip sheet ensures that oils from the standard roofing felt underlayment do not cause the underlayment to stick to the back of the metal. If this happens, expansion and contraction of the metal panels will tear the underlayment. As for installation instructions ... every metal roof is different. I strongly advise choosing a metal roof and then obtaining installation details from your supplier and the manufacturer. Depending upon what type of roof you choose, professional installation may also be suggested. If you choose a metal roof and cannot obtain installation details, please re-contact us with information as to the type and style of roof you've chosen and we'll do our best to provide installation details. Todd Miller
Todd Miller
Isaiah Industries, Inc.

9/25/2001
Can install 28g non-corrugated galvinized metal using strapping? It's for a gambrel roof and parts are 3/12 pitch. If so, how close does the strapping have to be?
Guest User

11/8/2001
advise house insulated garage unheated both shingled no leaks should they be stripped with 1x3s before installing metal? shingles on house drying out from not enough ventilation in attic any advise would be appreciated.we have mild winters in kentucky tnx Don Travis
Guest User

11/13/2001
advise house insulated garage unheated both shingled no leaks should they be stripped with 1x3s before installing metal? shingles on house drying out from not enough ventilation in attic any advise would be appreciated.we have mild winters in kentucky tnx Don Travis
Guest User

11/13/2001
We are having a home built by a large contractor. The drawings call for a very low pitch metal roof over an exterior porch. The dimensions are approx 11' wide x 7' deep. The trusses are pre fabricated and decked over with 1/2" OSB board. The underside of the porch is finished with painted MDO board. There are no vents. I would think that at a minimum the installer should place a 15# felt before securing the metal sections. The contractors specifications do not call for any underlayment. Will condensation on the back side of the metal cause pre mature failure of the OSB decking?
Guest User

12/18/2001
You have a valid point. Most building codes in North America call for an underlayment under all roofing products unless the product has been tested for use without one. This practice is generally to protect against severe weather situations such as wind driven rain or ice daming. Condensation is another form of moisture that is created whenever you get a temperature differance between surfaces and one surface crosses the dew point. Ventilation of enclosed spaces in a roof assembly is a good way to minimize the temperature differances and the resulting number of dew point crossings. Additionally, ventilation will allow the moisture to exhaust to the outside. The underlayment is referred to a moisture barrier in that it should allow air to pass through while trapping the moisture on its surface. If you were using a sheet steel roofing material laying directly on the deck, I would recommend either two layers of #15 or one #30 as the heat will eventually break down the felts. Most important though is to allow for some form of ventilation especially if you consider using a peel and stick type ice and water shield as an underlayment as it does not allow air to pass through. The entire roof structure will last longer if it can breath. Look at the old wood barns that have protected from the weather exposed to the elements for years. They are exposed both sides and can breath.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/19/2001