Can you install shingles over metal roofing?


Sheet metal is the alternative to the asphalt shingle that is used today to cover sloping roofs. If we tend to book the corrugated iron for a shed, a garage or other shelter, it would be wrong to dismiss this type of roof for his house.

The next time you pass heritage architecture, take the time to stop to observe the roof. The ancestral technique of installing a sheet metal roof is far from being forgotten.

But can you install shingles over the top of metal roofing? It’s not a good idea to try and install shingles over metal roof panels. While it’s perfectly fine to install corrugated metal roofing over asphalt shingles, it wouldn’t be a good idea to install shingles over corrugated metal.

If you want to install a metal roof, here are some tips to help you do it.

How to Remove Old Shingles to Install a Metal Roof

If you plan to install a metal roof on your home or garage, you will most likely need to remove old shingles first. If you leave the old shingles in place, the supporting structure of the roof cannot withstand the weight of the shingles and the metal roof. Your new metal roof must have a flat surface. If the shingles are not flat, they must come loose. This task requires a considerable amount of skill, it is only physically demanding, depending on how big the roof is.

  1.  Order a waste bin large enough to hold the old shingles. A single layer of lightweight shingles could weigh 225 pounds per 100 square feet of surface. Plan when the dumpster arrives, so you can get right where you want it. Set up the container so that you can drop the old shingles directly from the roof.
  2. Cover the shrubs under the eaves with plastic sheets while you work. This facilitates cleaning and protects the plants. Place plywood panels against windows and other fragile items to protect them from shingles that might fall from the roof.
  3. Loosen the chimneys around chimneys, drainpipes and other roof structures with a crowbar. If necessary, pry up the nails with the claw of a hammer.
  4. Slide the front edge of a shingle excavator under the lower edge of the upper row of shingles. If you do not have a shaving scraper, use a flat shovel to get under the shingles. Pull up the scraper or shovel as you push it to the top of the roof. This pulls up the shingles and their nails.
  5. Work your way through the top row of shingles, loosen and pull them up as you go. Go to the next row and loosen it. Also, pull up those shingles. Dump dumped shingles into a dumpster or other container so you can dispose of them properly. Continue this process until you tear off all the big shingles from the roof.
  6. Examine the roof skin for remaining nails. Pull up nails with a crowbar or the claw of a hammer. If you cannot get the nail out of the shell, hit the nail flush with the surface with a hammer.
  7. Use a spatula to scrape off roof tiles that could stay around the ventilation slots or wherever the roof was laid.
  8. Sweep the floor around the house with a broom magnet. This device picks up any nails that have fallen from the roof.
  • Things that you need
  • Trashcan
  • Plastic sheeting
  • plywood boards
  • crowbar
  • hammer
  • Shingle scraper
  • Garden shovel with flat blade
  • spatula
  • broom magnet

Tips

  • Plan this project for a time when there is no rain in the weather forecast. Have a few tarpaulins ready to cover the roof, just in case of unexpected rain.
  • If you remove shingles from a large roof, you will get some help. The sooner you tear off the old shingles, the faster you can install the new metal roof.
  • The new metal roof will cover all the nail holes that are in the roof of the shingles .

Warnings

  • When working on the roof extreme caution is required. Wear safety ropes and straps to protect you from falling. Wear shoes with non-slip soles. Only work on the roof when the surface is dry.
  • Do not neglect the magnetic sweep. Nails scattered around your house are dangerous when mowing or gardening. Landing in your driveway is a flat tire in your future.

How to prepare the surface to cover with sheet metal?

  • Measure the roof, anticipating the excess if you want the sheet to protrude from the edge of the roof, and dividing the roof width by three to find the number of panels needed;
  • Order your sheet steel panels by giving your roof measurements to the distributor;
  • Remove the old shingles by throwing them into a rented waste container and, by the same token, rent an industrial strength magnet to retrieve the nails that will fall from the roof;
  • Repair the structure by replacing or repairing damaged curbs and checking the strength of the structure;
  • Install a membrane to protect the roof from water infiltration, either tarred paper to nail or staple, or sticky sticker impossible to remove, to pose with a comrade;
  • Install the furs by screwing them around the pipes coming out of the roof, into the valleys, along the ridges and ridges, as well as on the rest of the roof;
  • Install the flashings on the fascia and on the gables, then install the valleys with nails;
  • Install a foam rubber membrane as needed to ensure a good seal.

Are you planning to renovate or install a sheet metal roof?

How to install the sheet on the roof?

The metal roofing is made of corrugated iron which is installed on the roof frame with roof screws. The metal roof screw pierces the metal panel to attach to the wood of the frame. The head of the screw is provided with a rubber ring that prevents water from seeping in.

The laying of the first ring is critical because they are two feet wide, but are often very long. You must measure and check the distance to be covered at the top and bottom of the panel to make sure the last piece of sheet metal is equal. The first sheet of sheet metal installed, you check the measurements and if everything is straight and even, you just have to lay the other sections of cover ensuring that the edge of the bottom of the roof is equal.

With the metal cover and trim installed, you use a protective sealant (sealant) to seal the joints between the “J” ledge and chimney and other items coming out of the house roof. Do not use tar on the surface as it will soil the finish of the coating with the flow of rain.

The corrugated form of the panels allows ventilation between the framing and the roof sections to prevent the formation of moisture and the appearance of mold on the materials. Their shape is made so that the sheet metal panel you install overlaps the previous one, while forming a joint that will not let the water through.

Note that there are pieces of sheet metal that fit into each other.

How to replace the existing roof with sheet metal?

According to Ecohabitation, it is possible to install a sheet metal liner without removing your asphalt shingles, unless you already have several layers of shingles. In this case, it is better to remove them to ensure proper installation of the sheet. The contractor will place a lattice on the asphalt shingles and put the sheet on the lath. Before that, we will make sure that there are no problems, water infiltration for example, that would have caused damage to the structure or insulation.

Does sheet metal withstand the northern climate?

Roofs coated with steel or copper should be inspected regularly to ensure that there are no cracks that will allow water to seep in. The temperature causes the metal to expand and contract. Thus, freezing and thawing cycles, as well as ice falls in winter use this material. Roofs with many skylights and valleys are more at risk. When the ice is detached from the roof, it can pierce the sheet by hitting the skylight or the edge of the roof. Galvanized sheet metal roofs must be repainted every five or seven years. Take this opportunity to inspect your roof and make the necessary repairs.

Offered in multiple colors, with a longer life and not absorbing moisture, many have often opted for sheet metal roofing. Here are four models that can be found:

  • Galvanized steel is a greyish white metal used in the form of sheets to cover a roof. This material is easy to work, it is very aesthetic, in addition to being resistant and waterproof;
  • The Canadian sheet is malleable and allows to marry the forms of roofs on slopes. The sheet metal overlaps diagonally on the roof, which minimizes the risk of water infiltration;
  • The baguette sheet is folded and stapled on a wooden stick. It is becoming more and more popular with new seamless laying techniques. These sheets are reputed to be very solid;
  • The sheet with pinched joints or standing joints can be recognized by its narrow joint and raised between the sheets. It has a similar appearance to the chopstick sheet, but its installation is faster and its tightness is foolproof.

Note that these sheet metal roofs used previously for homes and farms are ideal for your cottage or shed. You can even prune the roof to install a fan.

Ricky Kesler

Ricky Kesler has been an avid DIYer for years. Recently he's really taken to home security, but he has a lot of experience with all sorts of projects from Plumbing to Electrical and Framing to Tiling.

Recent Content