In this guide you will learn how to install a standing seam metal roofing system.
Image Inspiration Credits: John McManus & Group 3
For most homeowners and DIY enthusiasts, a standing seam metal roof installation is not a do it yourself project. But for those few who dare, let this serve as an introductory educational guide on how to install metal roofing on a small shed or a free standing garage.
if nothing else, you can still benefit from the basic conceptual understanding of the metal roofing installation process provided in this guide.
Materials and Tools you will need
* Sheet metal hand seamer aka folder or crimping tool.
* Wood cutting: For minor wood repairs, a cordless reciprocating saw.
* Hammer, rubber mullet, tool belt, metal snips/shears, tape measure.
* Safety rope, anchor and harness, and knowledge/experience using it, work safety plan, and first aid kit.
* Safe to use and adequate Ladder.
* Tear off/roof stripping tools, heavy duty contractor bags, and a dumpster to dispose of old shingles.
* Pre-measured and pre-cut Standing Seam Metal panels at work site.
* System specific screws and flashing details for your roof.
* Roofing Underlayment, Ice and Water, nails with colored caps.
Step 1 – Measuring Your Roof and Sketching a Diagram
Take multiple pictures of your roof from different angles, then measure your roof and draw a diagram that you can take with you to a roofing supply warehouse where you can order metal roofing materials for the job.
You will need to take precise/accurate measurements of your roof deck, and come up with an accurate/readable sketch/diagram of your roof; Ridge length, gables lengths (all sides), eaves lengths (all sides), valleys, dormers, chimneys, and skylights.
Although in theory, you can install standing seam metal roof over your existing asphalt shingle roof, I would advice you to tear off the old roof before installing standing seam due to a common effect of telegraphing of lines of asphalt shingles underneath the standing seam metal roof roof.
Note: You can get away with telegraphing of the shingles underneath, if you choose to install a metal shingles roofing system, instead of a standing seam metal roof.
Step 2 – Ordering Panels
You can order metal roofing panels called standing seam metal roof at your local roofing supply warehouse. They will ask you about the length of panels you need, type of profile you would like, and a color of your metal roofing system.
Hand over your roof diagram with all the details and roof dimensions, and show them pictures of your roof. Based on the information you provide, roofing supply shop will order the panels and flashing for your job. Here you can also buy all the necessary tools, and safety equipment.
In addition you will need to buy a roll or two of roofing underlayment for the job. I recommend that you spend a little extra, and go for a breathable synthetic roofing underlayment that will be installed underneath your new metal roof.
Step 3 – Preparing Roof Deck for Installation
Once you have all the necessary tools, and materials on site, You will need to prepare your roof deck for the installation of a new metal roof.
It is generally recommended that you perform a complete tear off of your old/existing roof so that you can get an opportunity to replace any rotten wood or plywood underneath the asphalt.
Step 4 Installing Ice-and-Water and Underlayment
Install synthetic breathable roof underlayment in a horizontal fashion, with sufficient tension in the underlayment from one side of the roof to the other. You will want to start at the eaves with a slight overlap of the roof deck, and nail down the first row of underlayment.
(If you live in a northern climate, then install one layer of Ice-and-Water right underneath your roof underlayment, adhering it (Ice-and-Water) straight to the roof’s deck with a half an inch of overlap past the eave’s edge.) You will also need to install ice and water in the valley/valleys of your roof.
You will then continue installing the underlayment in an upward fashion with a six inch overlap over the previous layer until you reach the ridge of the roof.
Step 5 – Installing Metal Trim, Drip Edge, and Gable Flashing
Now it is time to install metal flashing at the eaves. The flashing being installed over the edge of your roof’s eaves is called starter trim.
You will have to follow manufactures recommendations, but generally you would install your starter flashing leaving 1/4 of an inch of space from the eave, and securing it in place with system specific screws (that you should order along with materials) every 12 inches on center. Then, follow the same steps to install your gable flashing.
Watch the Video Below:
Step 6 – Installing Metal Panels
Once all the necessary metal trim/flashing is installed, you can begin installing your first metal roofing panel. You will have to cut, and bend about an inch of the panel underneath (forming a hook) so that we can hook it onto the starter trim/drip edge.
Then, the metal roofing panel will be secured by the special screws at the top. After that, you can secure the panel by installing special holding brackets/metal clips, and secure them with the screws to the roof deck.
You will find that metal clips will have two holes, one will be closer to the metal roofing panel, while the other will be farther away.
I recommend that you only use one screw to secure the metal clip through the farther/outside hole that is away from the panel. This will help prevent dents in the panel due to thermal expansion and contraction of the panels.
If your home is located in hurricane zone, you would want to put two screws into each clip. Never put two screws if you have solid boards underneath instead of plywood.
Both screws can easily split the board, which will compromise security of panel attachment to your roof deck. (The holding brackets attach to the panel on a side every 12 inches or so.)
The follow-on panel will be installed in a similar fashion. You have to lock the follow on panel into previous panel using the locking mechanism called the seam (Snap-Lock standing seam panel mechanism).
Use a rubber mallet, or a rubber handle of your hammer to snap the seams of the roofing panels together.
You can also snap the follow on panel with the palm of our hand starting at the ridge/top of the panel and working your way down until the entire panel is connected/attached via the snap-lock method. Then repeat the whole process again until you reach the gables/ends on both sides.
Watch the Standing Seam Metal Roofing Installation Video Below:
Step 7 – Installing Z – Bar Flashing
Note: If you are using a combination of ridge and soffit vent system on your roof, then make sure that your roof has sufficient pitch to prevent any wind driven water from getting inside your attic through a perforated z-closure.
Cut your z-bar so that it is the same width as one of the panels to which it will be fitted. Make sure that it fits well, but not too tight as to scratch the locks of the panel.
Normally, you will want to go about a 1/4 inch less than the nominal width of the panel. This gives you enough room for a snap lock of the next panel to fit in. You will also end up with only minimum gaps between the edges.
Cut a small piece of ridge cap (about two inches wide), align it so that it is in the center of the ridge, laying perpendicular with the locks. Mark the outer edges on the top of each rib. You will align your z-bars and the ridge cap to these.
Use your first piece as a template, then cut enough z-bars to accommodate every panel on your roof (have enough z-bars for both sides of the roof).
Using double-sided peel-n-stick foam, or some type of the exterior grade caulking sealant, caulk the connection area between the panel and the z-bar. I recommend that you use a clear (or color matching) Solar Seal 900. It works great. Attach the z-bar with three screws, and caulk the side gaps so that any wind driven water will not get in.
Once all of your z-bars are up and sealed, take a section of the ridge cap, and cut a 2-inch line down the center bend, at the end of the cap. At the same end, cut off 2 inches of the lock and bend down the two flaps. This will be your end-piece.
Align the flaps you have just made with the gable trim, and hook in one side of the ridge cap into the z-bar. If your z-bar is spaced too widely or narrowly, you can bend it in or out so that it fits your ridge cap.
Hook the second (unlocked) lock into the opposite z-bars all along the length of the cap. Once it is completely clipped in, use your hands to close the opened lock (lip) on one side of the cap, and then using the hand-seamer crimp down both sides of the cap.
* I recommend that you first practice installing metal roofing on a small structure such as shed, or a free standing garage before taking on your home’s roof. It would also be helpful if you can get another person who has experience with home improvements to help you out with your DIY project, and make sure that things go smoothly.
* Doing any type of work on your roof is inherently dangerous. There is always some inherent hazard of falling off the roof or from an improperly placed or poorly-secured ladder. You will want to wear special shoes with rubber soles, use a properly-secured ladder, and know how to properly use your safety equipment including rope, anchor, along with a properly-worn safety harness.