Installing Metal Roofing Insulation

What You'll Need
Spray foam insulation
Foam insulation
Duct tape
Plywood sheathing
Roofing Nails
Industrial grade paper
Paint roller
Fiberglass batts
Roof coating

There are a number advantages to metal roofing, the most compelling being cost and durability. Metal will not rot as most materials will eventually, and it usually can be installed for far below the price of most other roofing. This is balanced out by the fact that this type of metal roofing needs insulation to resolve sound and temperature issues.

Sound Issues to Be Addressed

Many metal roofs actually amplify sounds like rain, wind or anything hitting the roof. Insulation can help minimize what can be a distracting problem.

Energy Efficiency

Metal absorbs heat and in the cold it can exacerbate damp chilly conditions. This can make cooling and heating costs climb. Insulation is the best defense for high energy bills.

Installing Metal Roof Insulation

Step 1: Making Initial Adjustments

Locate where the roof joints meet. Lay your plywood at right angles with the roof joints. Fix them into place using the roofing nails. The best nails for the job would be either galvanized or stainless steel.  

Step 2: Layering the Paper

Layer the industrial grade paper over the boards to keep moisture out and to prevent leaks. This is important because this is a bad place for mold to get a toehold into the rest of the home or office building. Overlap the sheets to get complete coverage and fasten them using either heavy staples or nails.

If there is already a layer of plywood roof panels, there is no need for steps 1 and 2. Make sure there is a layer of a tough grade of paper already layered and if not fulfill this part of step 2.  

Step 3: Attaching the Batts

Place the fiberglass batts into the gaps between the sheathing and panels. Do not pack these too tightly. There should be a little air flow.

Step 4: Covering the Paneling

Use the ridge foam insulation to cover the wider spans of the paneling. If these don’t fit, cut them down to the size you need. Use staples to hold them in place.

Step 5: Getting Your Spray Foam Kit

If the metal roof has slopes, rent or buy a spray foam kit and liquefied foam. These are available from almost any hardware shop.  

Step 6: Patching the Hole

Cut a hole in the ceiling allowing you access to the roof framing. Spray the foam insulation into the hole using the instructions that come with the can as your guide. Do this quickly. The foam expands as it fills will oxygen filling the roof structure. You can then patch the hole you made back up with some drywall.

If you want, you can also covering the metal roof with an elastomeric coating. Use your paint roller and do the job rapidly as it dries quickly. Used on the outside the white tint will also reflect the sun and keep the roof cooler during the hot days of summer.