Those who aren’t familiar with house structure may not know what is decking on a roof. In fact, decking is an integral part of the roofing as a whole. To explain simply, the roof is constructed from trusses as the basic framework and joists as the baluster that supports and distributes the weight of the roof.
However, the space between the trusses and joists as the frame is empty. Roof decking is the extra layer attached to them, the flat surface that serves as protection between the roof and the home. It also contains weatherproofing features such as underlayment, shingles, and other attachments.
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What is Decking on a Roof?
What is decking on a roof exactly? The roof deck is the material that sits amongst the trusses and joists as the structural components and the weatherproofing and insulation layers such as coatings, roof materials, layers, etc.
Basically, the roof deck is a section where any other materials of the roofing are placed. The roof deck should be strong and durable enough to support the weight and cope with various conditions.
See Also : What is a Rake on a Roof
Roof Decking Thickness
Besides knowing what is decking on a roof, it is also important to know the typical thickness. The common thickness for roof decking is under ½ inch, or about 7/16 inch, to be exact. It is possible to find 3/8 inch plywood roof decking installed as this measurement once is considered adequate and acceptable. However, it won’t be as sufficient as the ½ inch ones.
Having a 3/8 inch roof decking layer is not a defect to the structure; however, you have to be aware of it as a homeowner. Some regions and states even have specific jurisdiction about being aware of the roof decking thickness from the constructor at the time being if the house is built using the old standards.
Types of Roof Decking
Now that you have learned about what is decking on a roof and its standard of thickness, it is time to dive further into the topic by understanding different roof decking types and what roof decking is made of. Several common materials are used for the deck, such as wood, concrete, cement, or steel.
It depends on the supported weight and affects the material that should be used. Other variables like rain, snow, and air conditioning weight might be added to the calculation.
For residential buildings
Plywood, groove wood, or tongue system is the most typical type used. Wood, in general, is strong enough to hold any roofing material weight, but it might need extra reinforcement for tile material.
For industrial or commercial buildings
Cement, concrete, or steel are more commonly found. The reason is that these buildings usually have larger structures, so they naturally need stronger structures to carry the equipment with more weight on the roof.
Whatever types of roof decking you are planning to use, keep in mind t the matter should be turned over to the professional expert in the roofing system. Having the installation done improperly might cause a dangerous impact in the future.
Roof Decking Boards
Moving on to the next part of the roof decking system, the following list below will help you understand what decking on a roof board, and several of its types are.
Tongue and groove
It is a board in 2×6 formation that consists of a “tongue” on one of the board’s edges that fits into the “groove” on the edge of a different board. The boards are slid together. It is common to be found in houses without ceilings, in which the boards add architectural elements to the joist.
It comprises planks and shingles that layered and placed in 1 ½ inch of distance between one another. It is most often found on old houses as it is an old decking solution.
This roof decking board also consists of distanced planks, but the boards are placed perpendicular to one another. It lets the airflow between the spaces under the shingles. The space between shingles installed may vary. It is used if you are installing cedar roofing shingles.
The boards are typically sized around 4×8 ft with plywood materials made from rigid, moisture-resistant, and mature trees. Having knots in the plywood may result in less uniformity.
OSB stands for oriented strand board. OSB decking is the most used roof decking type in modern buildings. The boards are about 16 ft or longer sometimes. The boards are made from interweaved and bonded wood strands created from rigid, moisture-resistant, and small trees.
You may need to learn about what is decking on a roof and its details if you want to replace your decking. Decking replacement doesn’t exactly equal replacing your whole roof. Discussed with professionals and experts in roofing systems to determine how much and what sections of your roof decking need to be refined.