You’d be forgiven for thinking that roof rafters and trusses are the same things. After all, they look relatively similar and certainly serve a similar purpose. There are, however, a good number of differences between the two with their own sets of pros and cons. The good news is that they’re easily distinguished during a roof inspection.
We’re going to share specifically what each is, explore the pros and cons of each, and try and explain which you’ll need, rafters vs trusses. This should help you first be able to identify what your current structure is using, consider your options for a replacement or roof repair, and then make an informed decision on which to use.
What Is A Roof Rafter?
We’ll start with roof rafters. If you’ve ever looked up inside a traditional barn or older building and you’ve seen lots of diagonal pieces of wood connected together to form large triangles, you were looking at roof rafters. They’re often made of wood but can be other materials and extend upwards from the hip of the building. They can also be connected to wall plates or downslopes.
They are structured in a way that allows contractors to lay a roof rack onto them, then all other materials that make up the roof such as underlayment, shingles, etc.
You’ll regularly find them in older buildings as they are the traditional, old-fashioned way of creating a roof. Each piece of wood is measured carefully, then fixed to other pieces in a variety of ways. More modern rafters are bolted together with high-strength nuts and bolts, older varieties may be simply connected into joins or grooves.
The actual slope of the roof is made from wider timber than the supporting level structure, this spreads the surface area of the roof and strengthens the structure. Once the roof is watertight, and an attic space has been created, insulation is stuffed or sprayed between the rafters.
The Pros And Cons Of Rafters
There are some who will always want to use rafters out of a sense of tradition, but that’s not the only benefit of using them.
More Space Internally
Rafters function in a similar way to a skeleton leaving large empty spaces underneath them, creating a large (sometimes quite airy) attic space. Many people choose to use this space as either long-term storage, an office, or even a full conversion that has bedrooms and bathrooms within. If you’re not looking for extra floor space, but want the feeling of airiness, then opening up the ceiling to expose the height into the rafters is a great way to create space.
Applicable To All Locations
Almost all buildings can have a roof created from rafters, and because they’re often cut to measure on-site, they can be created and installed in almost any location on the planet.
Little Forward Planning Required
In a similar vein to the above, rafters don’t need much forward planning. The timber is ordered in larger lengths and is cut to measure. That means no long lead times, and no issues with receiving the wrong size material.
Rafters are, however, more expensive than other roofing options. They take considerably more labor, and the materials themselves tend to be more expensive. Many people on tighter budgets opt for trusses rather than rafters for this reason.
Longer Installation Times
Rafters are considerably more exposed to the elements when installing. That means you’ll need to build structures to protect the roof installation or tarp over the whole thing if the weather isn’t going your way.
What Is A Roof Truss?
Now that we’ve covered the rafters, we move on to the other main roofing option, trusses. Trusses look very similar to rafters but are slightly different. They’re still made from timber but they’re designed specifically to support roof structures. Contractors using trusses will measure the size of the roof and order a number of trusses so that they’re installed at regular intervals and then connected horizontally.
They still sound very similar to rafters, but the core difference is that trusses are constructed off site and delivered whole. Rather than where rafters are cut and installed onsite.
The Pros And Cons Of Trusses
As with rafters, there are some pros and some cons to using trusses. Weighing up the pros and cons is an important part of the decision-making process when deciding on the debate of rafters vs trusses.
Stronger And Greater Span
Trusses tend to be both stronger and offer a greater span than rafters. If you choose trusses you might achieve a span of up to 60ft, whereas rafters can only achieve around 30ft. This is mainly down to the webbing within trusses that provides exemplary strength.
Easier To Install
Trusses come already fabricated and ready to install. That makes them far easier to work with and less problematic than rafters. The best kits will come numbered and marked against a plan, almost like an IKEA piece of flat pack furniture, meaning they’re incredibly easy to install.
Cheaper Than Rafters
You’re saving massively on labor costs when using trusses because they don’t need to be cut, crafted and installed in the same way as rafters. You might be looking at savings of between 30-50% against rafters when it comes to labor.
High Degree Of Accuracy
The trusses are crafted offsite, to exact specifications in a factory. That means you know precisely what you’re getting when they arrive. There are no errors on cuts and measurements, meaning fewer issues during installation.
Weight And Size
They are incredibly heavy and awkward in shape. That means they can only be delivered to certain sites without the need for large-scale cranes and machinery. Plus the shipping costs for trusses can be impressively large.
Seeing as trusses are fabricated to precise plans they can’t be edited or manipulated onsite. Plus, once in place due to the webbing, you’re unlikely to be able to use the space in the attic for much other than storage.
The Verdict: Rafters Vs Trusses
It really comes down to personal preference, long-term plans for the property, and your budget. If you’re looking to use the space in your attic for something other than storage, the property is in an awkward location, or you simply want a high vaulted ceiling, then rafters are a great option. If, however, you want to maximize your budget, you only need your attic for storage, and your property is easily accessed, then trusses might work better for you.
If you find yourself leaning towards trusses then you’re certainly not alone, in fact, the majority of Americans use trusses over rafters in modern times.
Rafters vs trusses isn’t a debate that is going to be settled in one article. The uses and variables are too many per project. Instead, consider the various aspects of your own project and make a decision based on your situation.
There are both pros and cons to rafters and trusses.
Always consult a professional before launching a new roof project.
If you do want to talk with some roofing experts, look no further than Trenton Roofing, especially if you’re looking for roofers in Freehold, NJ.
Alex Valentino – Vice President
Leading the way for the company’s second generation of family and employee ownership, Alex’s mission is to create lasting relationships built on trust and respect by providing uncompromising workmanship and unparalleled customer service. With a focus on safety and consumer education, Trenton Roofing strives to set the bar for the advancement of the roofing industry and the betterment of our local communities. When he is not working, Alex can be found traveling with his fiancée, watching football or playing a relaxing round of golf with his friends.