Metal roof installation, materials, prices and manufacturers

Standing Seam Metal Roof Installation

This installation guide is based on FABRAL nailing-strip standing seam metal roof, with 1″ ribs. Before you take steps to order materials and install the roof, we recommend that you thoroughly read this article and also check out other guides linked within, such as the roof deck preparation guide and roofing panels measuring guide.

When installing a standing seam metal roof, it is recommended that all asphalt shingles be removed from the roof to prevent / avoid the “telegraphing effect” where horizontally installed shingles punch through vertical metal roofing panels, creating ugly dents which cannot be fixed / removed. Also, since most standing seam metal roofs installed are steel, the granular surface of asphalt shingles will rub against underside of metal roofing panels and will scratch through the paint and galvanizing layer, which will cause metal panels to rust. Read the roof preparation guide to learn about roof tear-off, wood repair and installing roofing underlayment.

Another important thing to keep in mind is the metal roof itself. When ordering metal roofing materials, it is important to correctly measure the length of your panels, so that you don’t end up with panels that are too short and are unusable.

In a nutshell, measure the vertical run from the eave of the roof, all the way up to the ridge line, and order your panel at least 2 inches LONGER than the length of your gable / roof run. These two extra inches will be used for drip-edge hem. Not that typical standing seam metal roofing drip edge extends 1 inch beyond the eave, and then you need to make a reverse hem to lock the panel into the eave starter. There, go your two inches. You can use this standing seam metal roof panels calculator to estimate the number of panels you will need for your roof and the length of each panel. Note, that this calculator currently works of gable roofs ONLY. If you have a hip roof, DO NOT use the numbers from that calculator to order metal roof panels for HIP roofs.

Steel or aluminum?

In my opinion, aluminum is a much better choice of metal than steel, when it comes to standing seam metal roofs. Aluminum will not rust, and is the safest option to install in coastal areas. While most architectural steel standing seam roofs are made with high quality galvanized metal (usually Galvalume or G-90 steel), there is still that chance that you may place a few deep scratches onto the panels and it will eventually rust. While aluminum is more expensive than steel, I think the price difference is well worth it. Learn more about metal roofing prices for steel and aluminum standing seam roofs, as well as other types of metal roofing materials.

Installation Video:

Before you begin installing a standing seam metal roof, watch the video above a few times so that you have a very clear picture of what is involved in the metal roof installation process, and if you are able to tackle this big project.

Note to homeowners and first-time installers of standing seam metal roofing

For do-it-yourself homeowners, we recommend installing standing seam metal roofs ONLY on simple gable roofs, with minimum roof penetrations. If you have chimneys, skylights, dormers and/or valleys on your roof, we recommend you leave this task to professional metal roofing contractors, as the chance to improperly install roof flashing and other details is too high, and the cost of roof repair / installation of new roof will far outweigh the savings you will get by installing a metal roof yourself.

Installation Process:

image of standing seam metal roof installation

Eave trim / starter strip installation

The first flashing focused on is the WEF-1 eave trim, which is to be installed prior to the roofing under limit.

The WEF-1 is intended to be used on roof pitches up to six twelve. For roof pitches greater than six twelve, a two piece eave trim of WEF-2 and WEF-3 can be used. Within this video the WEF-1 will be used.

Place the top of the WEF-1 trim in line with the substrate and fasten to the decking eighteen inches on center with roofing nails. The eave trim will be fastened along the fascia with number fourteen screws spaced sixteen inches on center.

The next segment will show how to flash two eave trims that meet at a valley and a hip. Note the use of graphite pencils on painted steel will corrode it over time. Cut the trim as shown or needed and attach as described previously with roofing nails and screws.

Take note of the angles cut to allow for the trims to overlap. Sealant should be used between any trims that overlap.

Roofing underlayment

Now that all the eave trim has been fasted, the underlayment can be attached. Cover the entire roof with thirty-pound felt paper or titanium underlayment. Ice and water shield should be used at all valleys, chimneys and skylights. In cold climates ice and water should to be used at the eaves and extend twenty four inches past the exterior walls.

The installation of the underlayment is started at the eave at a gable end and rolled out parallel to the eave line.

Allow each consecutive course to overlap the previous by four to six inches.

Overlap the end of minimum of six inches when starting a new roll of underlayment. Areas that have been torn or cut should be replaced or repaired prior to installation of the climate guard panel. At side wall and end wall conditions continue the underlayment a minimum of six inches up the wall and fasten.

To prepare for installation of the first panel apply a bead of beetle sealant on the eave trim.

Details on cutting and hemming a panel

Make a mark one inch from the end of the panel and cut along the base of each rib with snips. Use the bending tool to form a hem under the pan.

Cut off the under lap rib completely. Remove leg and rib top from overlap rib with tin snips. Then tab around rib and cut flush.

Place an alignment line along the gable end, one half inch from the edge and square with the eave line. This is where the first panel will be started.

Set butyl sealant tape along the eave trim. Place the first panel with overlap leg along the alignment line. In cold weather, slide the panels tight again eave flashing, and in warm weather allow a gap for expansion. Fasten panel side with number ten pancake head screws and the top of the panel with three number fourteen mill points.

The second panel is installed in the same fashion. Place sealant over underlap rib before sliding hem over eave trim. Snap first two to three inches of panel together, and slide the panel tight against the eave trim, or with the gap depending on the temperature. Snap the panels together and fasten along the opposite side and top of the panel.

The eave hem can be tightened by crimping with duck bill Wise-grips or flanging tool after installation is complete.

Attaching gable trim over the panel.

To finish off the end, cut along the bends and fold top plane down ninety degrees towards eave trim and cut other flaps flush. To view other options on finishing off the gable review the clima-guard installation manual.

Install a bead of sealant tape along rib a panel, lay gable trim in place. Fasten along fascia board every twenty-four inches on center with number ten wood fastener or number fourteen mill points screws.

Installing ridge cap

The installation video above shows a vented ridge cap with RX10 Versavent material that is pre-attached before shipping.

Place the ridge cap over the panel and fasten with number twelve stitch screws through each rib. Overlap the next ridge caps six inches with sealant between the laps.

Optionally, you can install solid or vented Z-bar flashing between the ribs, and fasten them down with roofing screws. Use polyurethane sealant between the z-bar flashing and the metal roofing panel. Also, seal the opening between z-bar flashing and ribs, on each end of the z-bar. Apply sealant to the back side of the closure near the ribs and over the flanges to seal gaps.

Valley installation

image of Standing seam metal roof valley flashing

Focusing on the valley area, the first step is to place ice and water shield center down the valley. Cut the valley flashing to the angle and length needed to secure over the ice and water shield. Apply roofing underlayment on top of valley flashing.

In the installation video you can see the next flashing to be installed, is the WVC-1 valley cleat. You can optionally use a valley flashing with built-in reverse lock, which eliminate the need for valley cleat.

First apply a bead of beetle sealant tape to the bottom side of the valley cleat. Position the valley cleat six inches away from the center of the valley. Fasten with number ten pancake head screws at twelve inch spacing. Now that the valley cleat is installed we’re ready to start cutting and hemming panels for the valley.

Before installing the panels place a bead of butyl sealant tape along the eave flashing and on top of the valley cleat as shown. This is a shot of what the panel will look like and how it will be placed on the roof when finished.

Cut the climate guard panel at the appropriate angle in length to allow for a one-inch hem at both the eave and valley cleat. This is done by cutting along the rib so the bending tool can be used to complete the hem.

To finish off the overlap rib, cut the metal to allow the inside flap to fold over the opening where it can be cut flush with the edges.

Installing the panel can be done by placing sealant over the underlap rib and aligning the panel before snapping the panels together.

Once aligned, snap the panels together working from the eave up the run of the panel. Secure the top of the panel with number fourteen mill point screws. To finish off a panel at the gable end or side wall, first determine the width of the panel needed.

Many panels will not end as a full sheet and need to be cut and bent to make one inch high flange as shown in this picture.

Using the bending tool, bend the one-inch flange down the length of the panel. Partial bends may need to be performed along the length of the panel for longer runs till the desired bend is achieved.

If the panel is used for a gable end, attach sealant along the one inch high flange, and secure with the WGF-4 gable trim as previously described.

image of Standing seam metal roof sidewall

For demonstration purposes in the installation video, the panel is used as a side-wall condition with the double WSW-4 flashing. Place a bead of sealant over the one-inch flange and set the flashing in place and fasten with number ten pancake head screws every twelve inches on center.

Installing hip-cap, using the hip cap enclosures

image of Standing seam metal roofing - installation of hip cap

The method shown will use a J-trim and an asphalt impregnated sealer strip to close off the void created between the hip cap and the flat portion of the panel.

First place butyl sealant tape in the pan of the panel where J-trim will go. Cut J-trim to the desire shape and position the trim in the pan of the panel over the sealant. Screw fastened trim to the panel with number ten pancakes screws or number fourteen mill point screws.

Use one part polyurethane sealant up the back side of the closure near the ribs and over the flanges to seal gaps. If using asphalt impregnated sealer strip as shown in the top left panel, lay the strip across the panel and apply beetle sealant on top and bottom. When the top of the panel meets a wall, it is finished off by using a closure strip with beetle around the perimeter and set in place on the panel.

Place a line of sealant across the tops of the J-trim and closure strip before attaching the hip closure.

Place the hip cap down and fasten with number twelve stitch screws at every rib. Note the bottom of the hip cap was bent down to give a finished appearance.

Returning back to our end wall condition, place the WEW-2 flashing over the closure and screw through the main ribs with number twelve stitch screws.

The end…

This was a quick run-through the most common standing seam metal roof installation techniques and details. In the next series of metal roofing installation articles, we will go over each detail in-depth. We will also cover measuring a roof, installing roofing underlayment and roof-top safety procedures, as well as go over metal roof installation tools.

If you will be installing a standing seam metal roof yourself, it is best to buy materials from a local metal roofing manufacturer / supplier, as most of them make standing seam metal panels right on the job-site, and this way you can avoid paying high shipping costs, and often not pay any sales tax :).

Written by Leo - roofer with a vision. Follow Leo on Google+

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Written by admin

Posted on November 1st, 2012 at 4:31 pm

Posted in Metal Roofing Installation

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