The roof decking is arguably the most crucial part of the roof. It supports the shingles and other

waterproofing materials and protects your home from fire. Because of this, it’s necessary to

choose nothing but the best materials when building or repairing a roof deck.

What materials can you use to build a roof deck? Can you use composite decking boards for

roofing? And what are the best materials that you can use?

Composite Decking Boards for Roofing

When building a roof decking, you want something strong and durable, since it will be

supporting a heavy load. You also want something weather and moisture-resistant, and easy to

install. Composite decking boards seem to fit all those things, leading people to believe that they

can be used for roof decking. But can you use them for roof decking?

Using wood boards is an excellent choice when building roof decking. However, Wood-plastic

composites (usually used in decking) are not ideal materials for a roof deck. You will not see

anyone building a roof deck with composite decking boards, for several good reasons.

Why should not you use composite decking boards for roof decking? First, composite decking

boards are meant for a different purpose, and that is to build patios and floors.
They are not 
designed to be used in the roof—the best stay in your garden or outdoor spaces. Second,

composite materials are quite expensive. More cost-efficient alternatives can do the job better.

And third, roof deckings should be able to support heavy loads. Since most composite decking

boards are heavy themselves, they are not quite suitable for the job. 

So next time that you are planning to build or repair your deck roofing, skip the composite

decking boards as an option. 

What Materials Should You Use For Roof Decking?

If composite decking boards are off the table, what materials can you use to build a reliable and

durable roof decking? Here are some of the best and most used materials for deck roofing.

1. Plywood – Plywood is one of the most preferred materials for residential roof decking.

It’s made up of veneered layers of thin wood in alternating grains. It’s the go-to material

for wood sheathing. It’s cheap, strong, durable and flexible. It comes in a standard 4-by-

8-foot sheet, covering a wide area. For roof decking, 5/8" CDX, 1/2 inch plywood is

often used.

2. Oriented Strand Board – Oriented Strand Boards (OSD) are the most common material

used in building roof decking. Like plywood, it is made up of intertwined layers of wood

strands in alternating grains. Similar to plywood, it comes in standard 4-by-8-foot sheets.

 

The only difference is that Oriented Strand Boards are cheaper than plywood, which

makes it a solid choice for people who want to save costs. However, many builders

believe that they are not as strong as plywood. Another problem with oriented strand

boards is they are more prone to moisture, moulds, and mildew. 

 

3. Concrete – In some cases, a more durable and stronger roof decking is necessary,

especially for non-residential buildings. For this, many builders consider concrete

decking. There are a lot of benefits to using concrete. First, they offer maximum

protection from fire. Second, they reduce the effects of wind damage. And lastly, they are

quite easy to clean and maintain. It’s also more eco-friendly than using plywood and

OSB. However, before using concrete, make sure that your house is strong enough to

support the weight of the concrete.

4. Steel Decking – Often used in commercial buildings, steel roof decking is one of the most

durable and strongest decking options. They are resistant to warping, moisture, weather,

and pest damage. While may not be as much as plywood, they’re considerably lighter

than concrete. On top of that, they are also excellent energy savers, as they can reflect

heat during hot days.

There are many other options for roof decking. To know which one is the best for you, feel free

to consult a professional roofer. They can help you explain which one is the best in more detail.