How to Insulate an Aluminum Roof
The aluminum roof is durable, low maintenance and easy to install. However, any metal roof risks a loss of heat and precipitation which directly affects its efficiency. For this reason, it is necessary to properly insulate it. There are a wide variety of insulation materials and solutions available in the market, but you can follow the steps below for the conventional insulation process.
Step 1 – Clean the Underside of the Roof
If your aluminum roof is already installed, clean the underside of the roofing before you begin. Use a light acid cleaner or water mixed with chlorine. There are many aluminum roof cleaning agents available in the market which you can use as well.
Step 2 – Fill in Gaps and Holes
An installed roof will have plywood support beams under it, and will have screws and nails set into it. It is important to seal those and any other holes in the roof to ensure that there are no leaks. If the roof is not properly sealed, there are chances of leaking and an inefficient insulation.
Step 3 – Install the Fiber Glass Bats
Once the roofing is properly sealed, attach the fiber glass bats at spaces (packing fiber glass bats close together reduces its insulation capacity). Use adhesive or duct tape to hold them in place. Avoid using nails as they can penetrate through the aluminum roof.
Step 4 – Install the Foam Insulation
Place the rigid foam insulation sheets adjacent to each other perpendicular to the plywood foundations. Use these to cover the under roof, cutting them up according to size . Hold them in place using nails or staples made of galvanized steel, which is is rustproof.
Step 5 – Taping the Edges
Seal the edges of the foam insulation with duct tape, going all around, properly sealing all open edges. You can also use a light mortar or plaster to cover up and fill out spaces.
Step 6 – Use Spray Foam for Inaccessible Areas
Some inaccessible areas such as corners in attics with slanting or vaulted ceilings are hard to reach. To insulate these areas you can use spray foam insulation. Spray foam insulation comes with a kit and a user manual; you can use it all over the roof as well, but it is advisable to spend some extra time and effort to do your own insulation. When insulating those hard to reach places with coverings you will need to use a drill machine to make an appropriate sized opening in the ply wood and spraying through that hole.
Step 7 – Finish Up
Finish up with a coat of paint covering the duct tape and the insulating foam. Rigid insulating foam sheet are also available in decorative designs and patterns at a higher cost. Use according to your needs, if the insulated roof is in the attic than you do not need fancy finishes.