Can TPO Roofing Be Installed Over Plywood? Answer Here 2023

TPO has gained popularity as a result of its durability, cost-effectiveness, UV and heat resistance, and energy efficiency. But, I think you are quite confused about can TPO roofing be installed over plywood.

Why take too much stress? We are here for you. And yes, you can install TPO roofing over plywood, but directly on top of the plywood is not a good idea.

So, for more information, stay with us.

Can TPO Roofing Be Installed Over Plywood?

If the nails of plywood pop out, it will be a disadvantage for the TPO roofing. So, before installing TPO roofing over plywood, you’ve to follow a guideline. And, here we’re with a guideline for you.

Why Can TPO Roofing Be Installed Over Plywood?

If you’re not that fond of OSB, you can use CDX plywood with a thickness of 4 plies. TPO can also stick directly to T&G. But for the greatest results, you can use ¼” plywood over T&G and then the TPO membrane.

How Can TPO Roofing Be Installed Over Plywood

Installation of TPO roofing over plywood can be divided into some steps and the steps are explained in the rest of the article.

Step 1:

Replace any damaged decking with new decking of the same thickness. Remove the old, rotten, and replace it with the new, fresh.

Step 2:

Then, install plywood over T&G. Be careful of the thickness of the plywood, and don’t forget to fasten it properly.

Step 3:

Throughout the whole substrate, Install a ½” thick cover board. If the roof isn’t heavily trafficked, 1” ISO will work. Remove and fix everything that is rotting. Covering up decaying wood is a bad idea.

Step 4:

Now, you can install the TPO in three different ways. The methods are fully adhered, mechanically attached, and ballasted.

The membranes are attached to the substrate using a particularly strong adhesive that produces a chemical link with the TPO when the TPO roof is fully adhered.

The term “mechanically attached roof” refers to the use of a particular screw-type fastener to secure the roof to the substrate. The sort of fastener you use will be determined by the type of substrate you have.

Adjacent TPO membrane sheets are overlapped, covering the fasteners and plates. And welded together with a minimum 40 mm (1-½”.) broad hot air weld in this method.

And, ballasted means the TPO is laid over the top of the roof, thoroughly sealed all around the perimeter and at all penetrations. Then, a ballast is placed on top of it to keep it in place.

Ballast is usually smooth, spherical river rock with a diameter of 2′′ to 3′′. The rock is spread out at a rate of 1,000 to 1,200 pounds per square foot of roof (100 sq. ft.). Concrete pavers, which weigh about 20 pounds per square foot, can also be used.