This article will give you step-by-step instructions on how to install a standing seam metal roof. Most DIY’ers and homeowners may not think of installing a standing seam metal roof project as impossible. However, that’s not the case, so this guide is for those who would like to give it a go! Even if you don’t ever take on a project like this, this information will help you understand the installation process for metal roofing.
Do not try this for the first time on a more massive structure, like your home. Practice installing a metal roof on a smaller structure, like a small shed or garage. You might also consider having someone with experience help you with your project to ensure things run smoothly.
A Word of Caution
It is, by nature, dangerous to work on a roof. There is a risk of falling from the roof or an unstable or poorly placed ladder. Be sure to take safety precautions and learn to properly use safety equipment to keep you safe, such as wearing non-skid shoes, safety harnesses, and ropes, etc.
From various angles, take multiple pictures of your roof. Measure your roof and draw precise diagrams—you will take this to the roofing supply store and order the job materials.
Your sketches and diagrams not only need to be legible but they need to include exact measurements of your roof deck—it should include the length of the ridge, gables, and eaves of all sides, valleys, chimneys, skylights, and dormers.
Tip: You could, in theory, install a standing seam roofing system on top of your existing asphalt shingle roofing system, but it is always better to remove the old roof first because of the effect of telegraphing of asphalt shingle lines under the metal roof. If you want to get around the telegraphing of shingles, you could instead choose to install metal shingles rather than a standing seam metal roofing system.
Standing seam metal roofing panels are available to purchase at your local roofing supply store. You will only need to know the panel lengths, profile type, and the color.
This is where your diagrams and pictures will come in handy because it will have all the details of your roof, including dimensions as well as the pictures you took of your roof.
The roofing supply company will be able to order the flashing and panels you need based on the information you provide them. They should also be able to order any other tools and equipment needed to complete the job.
Don’t forget to buy the underlayment for your roof—it comes in rolls and is installed under your metal roof. Although it may cost a little more, you should consider buying a breathable synthetic underlayment for your roof.
Begin preparing your roof deck after you have ordered and received the tools and supplies for your new metal roof.
At this point, you should consider completely removing the old roofing system. This will enable you to not only work from a fresh starting point but also give you the opportunity to make any repairs to the wood on your roof.
Be sure to take safety precautions while preparing your roof.
Note: Those who live in cold climates may want to install a layer of ice-and-water below the underlayment—it should adhere directly to the deck of the roof (overlap the eaves by ½ inch). Don’t forget to add the ice-and-water to the roof valleys.
Begin installing the underlayment horizontally with plenty of tension. Start from one side of the roof. Slightly overlap the roof decks at the eaves and nail down the first underlayment row.
Working your way up the roof to the ridge, continue the installation of the underlayment, overlapping each layer by six inches.
At this time, you will install the starter trim, which is the metal flashing that goes over you’re the edge of the eaves.
Always follow the manufacturer’s instructions, but as a rule, leave a ¼ inch from the eave when you install your starter flashing.
Every 12 inches, secure the starter flashing in place with the screws you ordered specifically for your flashing.
To install the gable flashing, follow the same steps as you did with the starter flashing.
You can start installing the metal roofing panels after you have installed all the trim and flashing. Form a hook by cutting and bending approximately one inch of the panel to hook it to the starter trim below the edge.
Then, use special screws at the top to secure the metal roofing panel. Install special metal clips or holding brackets with the screws to secure the panel on the roof deck.
The metal clips should have two holes–one that is close to the metal roofing panel and one that is further away.
To help prevent thermal expansion and panel contraction dents, it is recommended to use just one screw through the outside hole, furthest from the panel.
Only use both holes if you live in a hurricane-prone part of the country. If you do not have plywood under the panels, never use two screws.
Doing so will split the board, compromising the attachment of the panel to your roof deck.
You will install the follow-on panel in a similar way. Using the seam, or locking mechanism, lock the follow-on panel into the previous panel.
Snap the seams of the roofing panel together using a rubber mallet (or with a rubber handle of a hammer).
Alternatively, using the palm of your hand, snap the follow-on panel by working your way from the ridge of the panel to the bottom—using the snap-lock method, make sure the panel is connected from top to bottom.
Do this until you get to the gables on both sides.
You will cut the z-bar to the same length as the panel it will be fitted to. Make sure it fits securely but not too tight, because it could scratch the panel locks.
Cut the z-bar about a ¼ inch smaller than the panel width so there is enough room for the next panel’s snap lock to fit inside. You want the smallest possible gaps between the edges.
When using a combination of soffit and ridge vent roofing system, be sure your roof has enough pitch to keep wind-driven water away from a perforated z-closure, which could get into your attic.
Cut a piece of ridge cap to about two inches wide and line it up to the ridge’s center so that it’s perpendicular to the locks. Your ridge cap and z-bars will be in alignment with these.
Using the first piece as a guide, cut the number of z-bars you need for each panel of your roof (on both sides).
Caulk the connection space between the Z-bar and the panel with exterior-grade sealant or double sided peel-n-stick foam. It is best to use Solar Seal 900 either in the same color or clear. Using three screws, attach the z-bar. To prevent water from the wind from getting inside, caulk the side gaps.
After you have placed and sealed all of the z-bars, create your end piece by cutting a two-inch line down the center of a section of the ridge cap. Then cut two inches off the lock at the same end and bend the flaps down.
Line up these flaps with the gable trim, hooking in one side of the ridge cap into the z-bar. Bend it accordingly so that it fits the ridge cap.
The unlocked lock should now be hooked into the opposite z-bars on the cap. Using your hands to close the open lock after it is completely clipped in. Then, use the hand-seamer clip to crimp down the sides of the cap.