Are you planning on resheathing your roof? If yes, you will need to use H-clips. This post will help you understand what H-clips are and how they can benefit your home and roof structure.
According to International Residential Code (IRC) 2006, builders must use H-clips in roof constructions. While all jurisdictions don’t comply with these regulations, one or two H-clips will allow your roof’s trusses and rafters to enjoy a longer life span.
H-clips provide a bit of cushioning and safety net to your sheathing during the expansion and contraction of the plywood sheets due to weather changes. Let us dive in a little bit deeper to understand why H-clips are important and how they can benefit your roof sheathing.

What Are H-clips Used For?
Roof sheathing is commonly known as roof decking. This is a process where you install a wooden board (mostly plywood) to form your roof’s foundation. The term foundation sounds appropriate because this roof sheathing will act as a base to rest your shingles and other roofing components.
You will require tiny metal clips called H-clips as you lay this foundation. They are called H-clips because they look like the letter “H.” The main purpose of H-clips is to hold two of your roof sheathing planks together.
This will help stabilize your roof decking while providing enough space between the wooden planks throughout your roof to expand due to weather conditions.
What If You Do Not Use H-clips?
Even if H-clips are not a requirement as per your area’s building code, using them to install planks or wood panels in your roof sheathing can prove beneficial. If you opt not to use H-clips, the wood planks or panels will join together and may buckle during expansion and contraction. This will cause bumps and waves on your roof, making it look ugly. Furthermore, it will also affect the integrity of the structure with the passage of time.
Other disadvantages of not using H-clips include leaks due to damage to the planks. Furthermore, the bumps between the planks can also lead to poor water drainage on your roof. At worst, this will make your plywood foundation weaker, and you’ll be living with the risk of your roof falling through.
Is H-clips Mandatory For Roof Sheathing By Code?
While using H-clips is not an automatic requirement, responsible roof installers use H-clips for roof sheathing.
According to International Residential Code (IRC), roof construction contractors must use H-clips for roof sheathing or wherever required. However, not every jurisdiction follows IRC regulations. So what if your home is an area that requires H-clips for roof sheathing, but it was built before the IRC code came into effect? In that case, your home is not in violation of the code.
½ inch nominal or 7/16 inch solid sheathing is the most common form of roof sheathing. In these trusses/rafters, you do not require any H-clips at all. However, using them will ensure the safety of your roof sheathing and help prolong your roof’s structural lifespan. A couple of H-clips between the trusses/rafters will do the job.
Remember, if you are looking for support for planks with maximum lengths, it is recommended to use H-clips. While you can use one clip per span for a nominal size, it is best to use two H-clips for spans that are 48 inches or more in length.
Why Are H-clips Required For Roof Sheathing?
H-clips can help provide adequate support to your roof’s panels and help them stay in place. If there are H-clips missing in your roof sheathing, you will be able to feel the discernible structure because of the slight flexing as you step on the edge of unsupported plywood.
Using H-clips for roof sheathing reduces any buckling of your roof’s edges over the years. So, even when it is not mandatory for you to use H-clips, using them is always a good idea. If the surface between the trusses of your roof surface is sagging, it’s due to the lack of H-clips.
Where to Place H-clips On Roof Sheathing?
You can use H-clips in the rafters, trusses, or joists of your roof’s foundation. You will require two equally spaced H-clips and should place them between supports.
Let’s suppose you have a span of 40 inches. In this case, you can place a single H-clip right in the middle of the installed plywood and then install the other sheet by fitting it within the H-clip’s hook. So, remember this rule of thumb. You can use 1 H-clip per bay in your rafter cavity.
You insert the H-clip over the edges of adjacent plywood panels. This will reduce the deflection of the edges between both panels.
Benefits of H-clips
There are numerous benefits of using H-clips in your roof sheathing process.
- Even if you do not require the use of H-clips, using them will increase the stiffness of the panels used for roof sheathing.
- The H-clips will enable equal weight distribution between two adjacent panels supported by the same clip.
- With H-clips, your panels are less likely to deflect when bearing a heavy load near their edges.
- When you use thinner panels for roof sheathing, H-clips can increase their stiffness and prevent any bowing/bending under heavy weight along the edges.
- Using H-clips will reduce your overall construction costs as you will require lesser material.
- As a builder, you may require fewer rafters when using H-clips. This has two benefits. First, it will allow you to create bigger rafter bays. This way, you can support longer panels using multiple H-clips. Secondly, you will be able to finish the project more quickly.
- You can use thinner sheathing to reduce the cost of the project. This is a great way for homeowners to save money. On the other hand, if you’re running a roofing company, you can use this advantage to offer solid quality roof sheathing at lower prices.
Conclusion
While H-clips will not prevent your wooden panels from breaking, cracking, or buckling, they will definitely hold them in place to ensure the structural integrity of your roof sheathing. Even when using H-clips is not mandatory in your jurisdiction, it can help you prevent issues of warping and buckling due to the wooden panels expanding.
Connecting your panels with H-clips in the middle leaves enough space for adjacent panels to expand without warping. Plus, the use of H-clips ensures the consistency of the gap between panels throughout your entire roof structure.
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