If you realize that your galvanized metal roof is leaking – find out where it’s coming from and fix it now! If you don’t manage to fix the problem right away, you’re going to end up with permanently damaged walls, flooring, windows… and a whole host of other problems. Get up there and figure out where the leak is coming from – and wherever possible, try to work from a ladder for your own safety.
Hopefully, all you’ll need to do is patch a small seam. However, if you find that you need to replace an entire section of your galvanized metal roof, things will be a little more difficult. Keeping safety in mind and working with a partner, here are the steps you need to take to replace an entire section of your metal roof.
Step 1: Assess the Damage
1) At the location where you find the damage, you’ll want to use a power screwdriver to loosen the J-rail. This will remove the screws along the rail on both sides of the roof where new material needs to be placed down. Although it’s not necessary to remove the J-rail entirely, it needs to be loose enough that the new metal sheet can fully and safely slide underneath.
2) Using a high-powered flashlight, look underneath your roof at the interior to assess the damaged area. Get rid of standing water and replace any damaged insulation. You may also need to replace or repair damaged rafters or roof trusses, and then allow the area to dry out before continuing to overlay the roof. While you don’t necessarily need to remove the damaged piece of metal, you may have to use tin snips to cut away the damaged area to gain access to your attic or other part of the roof that needs repair.
Step 2: Prepare Your Materials
3) Cut a new sheet of galvanized metal roofing to the same length as the piece that was damaged, but make it just slightly longer than your roof’s width. It should be around a foot wider on either side of the damaged metal area as well.
4) Along the edge of the new galvanized metal sheet, place 2” butyl tape across the long, bottom edges. Don’t bother taping under the short edges, as they will simply slide underneath the J-rail and should not be visible.
5) Place the new galvanized metal sheet overtop the damaged metal sheet, being very careful, and make sure the piece is long enough that it can fit underneath the J-rail on either side – DO NOT attempt this process yourself. You should both be wearing heavy-duty gloves, arm and neck protection. Severe injuries from galvanized metal sheets are far more common than they should be and may require hospitalization. The sheets can cut extremely deep, so be careful and take all available precautions. Do not rush this step for any reason whatsoever.
Step 3: Attach and Seal
6) After the new sheet has been slid underneath the loosened J-rail, place butyl tape along the edge of the roof where it won’t be seen when the J-rail is reattached. New screws can then be placed all the way through the J-rail and tape, new metal, and into the side of the house. This should be done on both roof sides.
7) Moving up to the top of the roof, insert screws through everything but the roof rafters – the screws should go through the new sheet of galvanized metal, the tape, and the old damaged sheet. Space the screws two inches apart, keeping in mind that if the metal still isn’t sitting flat to the roof afterward, you can go back and add another screw every inch.
8) Use a high-quality metal coating to seal the edges of all four sides, as well as the seams. Allow this to set, and you’ve completed a galvanized roofing repair.
See Also: Metal Roof Maintenance