Skillion Roof: Advantages and Disadvantages

Last Updated on October 10, 2021 by Kimberly Crawford

What is a skillion roof?

Skillion roof has defined modern and minimalist roofing styles. In contrast with standard roof types, skillion roofs do not have two sloped sides meeting at the ridge. It only has a single flat surface with a steeper and more standout pitch.

The two main types of skillion roof would be the oval-shaped and the butterfly design. But in modern designs, there is also the split skillion and the multiple skillion sections. Each of these offer a certain modern vibe. 

The butterfly skillion is more recent and is specifically designed to collect rainwater. It is made of two skillions angled to the center, creating two wing-like ensembles as it drapes down.

Skillion roofs do not require tight sealing and are made from standard roofing materials using metal or rubber finishes. Skillion roofs are also called pent roofs, shed roofs, lean-to roofs and mono-pitched roofs. 

Related: 25+ Parts Of A Roof And Their Functions (Explained and Pictures)

Skillion roof advantages

house plans with skillion roof

Before installing one, you must know the benefits that you would be getting from having a skillion roof for your home. 

  • Water drainage: Unlike most flat roofs, skillion roofs do not encourage water puddling. At a pitch of just 1:6, skillion roofs efficiently provide water runoff, and as such, inhibits water ponding and offers better water drainage. 
  • Easy to construct: Due to its uncomplicated construction, skillion roofs are also relatively more affordable than other roof types. The single, flat surface of the roof would not take on a lot of construction materials and the shingles would cover lesser areas. It also costs less in maintenance compared to standard flat roofs. 
  • Skylights: Needless to say, the right pitch and steepness of skillion roofs give you the chance to install solar panels or skylights in your attic room. These are cost-efficient and aesthetically valuable fixtures that are essential in daylight and overall energy saving. 
  • Privacy: With the right angling, you can easily block off the side that is closest to your neighbor’s block. From there, you can make your solar panels for more natural light. It is also extension-friendly so if you need extra cover for new structures in your home, you can go for a skillion roof. 
  • Modern vibe: The minimalism of skillion roofs is always their best benefit, visually speaking. It is neat, symmetrical but at best, unconventional. With these characteristics, you are given more liberty to think outside the box when it comes to beautification and landscaping styles. 

Skillion roof disadvantages

While clean and almost perfect, skillion roofs also have minimal disadvantages. So, here are the things you have to look out for before installing one. 

  • Compact attic space: One of the most noticeable drawbacks of skillion roofs is the lack of attic space or loft area. It has tighter angles compared to gambrel or gable. If you are one who would want to convert the attic into an added living space, you may want to rethink that decision. 
  • High wind vulnerability: Note that roofs with multiple slopes are more invulnerable to high wind damages compared to simple roofing and less slope roofs like skillion. If your decision is final and you still want to carry on with the skillion, you need a good contractor to weatherproof it. 

Types of skillion roof

As have been mentioned, there are different types of skillion roofs and in this section, we would briefly describe them. 

  • Butterfly skillion roof: It is also called the double skillion. For this, two straight sections sloping down on a side and running towards a center point is built. This creates two wings, hence, the name.
  • Oval skillion: This one is a curved skillion instead of the usual straight and steep slope. If you want a more organic look for your minimalist home, this is the skillion roof that you should try. This is also practical in creating more space for the indoor area. 
  • Split skillion: This one is the fusion of skillion and gable roof. 
  • Multiple skillion sections: This one is a skillion roofing at different heights. It adds more aesthetic appeal but at a cheaper rate compared to other roofing types. 
  • Reverse skillion: When the steep slope of a skillion roof falls to the back of the home or shed, it is called a reverse skillion roofing. 

Suggested roofing materials for a skillion roof

You can still use all types of roofing materials when it comes to a skillion roof but the following would be the recommended roofing materials for it. 

  • Standing seam metal roof: Aside from its longer lifespan, it is also considered as the best pair for skillion roofs. They also offer more minimalism to the overall look of the skillion. 
  • Wood shingles: This roofing material always gives a timeless look to any roofing type. But more than this, it is beneficial in adding insulation to the skillion. It is perfect in giving off a cooler vibe for the home plus, wood appeal is beautiful without contestation. 
  • Asphalt shingles: Aside from being a versatile material to any roof shape and type, it is also a more affordable option compared to wood. If you prefer this material more, know that you have a wide range of textures and colors to choose from. However, you may need a reputable contractor to install asphalt shingles on a skillion. 

Related: 19+ Different Types Of Roof Shingles (Materials, Brands, Pros, Cons, Cost)

How much does a skillion roof cost?

Because they are built directly on rafters, the estimated cost of skillion roofs is in between $6000-12000 because the construction materials are still vary per design type. Skillion shingling would typically cost less compared with metal covering. 

How to build a skillion roof

This roof is generally considered as a standalone roof meaning that they do not need to attach to any part of the roof system. Its primary construction components would be wood shingles, asphalt, and metal. It is then finished with a standing seam metal to reinforce its structural integrity. 

The main considerations when it comes to this type of roof design would be the pitch level, the rafters, and the thickness of the beam. While DIY skillion roofs are becoming a thing, it is still more commendable to have a contractor to do it. As for how to build a skillion roof, here is a step-by-step visual to refer to. 

Skillion roof house ideas

So, what can we expect out of skillion roofs? Here are some skillion roof house ideas that will surely inspire you to install a skillion roof for your home. 

Industrial look

1 industrial house with skillion roof

For a grid look home with lots of natural light sources, a skillion roof would be the best fit. Aside from the minimalist vibe, it is also captivatingly industrial overall. The monochrome of the home also brings out the modern out of that skillion roof.

Split skillion

2 split skillion roof plans

This type of skillion roofing is perfect for clerestory windows. This look evokes a contemporary zen thanks to the fine angles of the split skillion roofing. It is, however, softened by the warm lights and the horizontal clerestory windows are the perfect source of natural lights while maintaining the privacy of the home. 

Skillion roof garage shed

3 skillion roof garage shed

For a more unified look, you can extend the skillion roofing to the garage to create a shed like look. The single slope can be steeper by the garage to cover extra shade on the sides. It can look like this. 

Swanbuild

4 swanbuild skillion roof

This one features a flat roof on a skillion. It is cozy and chic which really gives a classy, homey vibe for this bungalow home. 

Skillion roof vs pitched roof

Pitched roofs are part of the more conventional roofing system and compared to skillion, they are more efficient in snow runoff. They are also a better choice when it comes to more headspace and ventilation in attic rooms. Structurally speaking, they are also sturdier and more dependable because they are attached to a roofing system and not just the rafters. 

On the other hand, skillion roofs are more economical not just in terms of construction but also in terms of maintenance. They are also less vulnerable to drainage problems compared to pitched roofs. It is also the perfect roof type for solar panel bases which makes the home not just modernly noticeable but also energy efficient. 

Gabled roofs vs skillion roofs

While skillion roofs are also called shed roofs sometimes, gabled roofs are the classic shed roofs that we see in barn style homes and farmhouses. The common claim is that skillion roofs are cheaper than gables. While it is true on more compact homes, gabled roofs are cheaper for larger covers compared to skillion. 

Structurally, gabled roofs form a triangular shape because of its two slopes intersecting at a ridge while skillion roofs are sloping downwards to one side. Gabled roofs are also evenly ventilated compared to skillion and give more headspace than that of skillion roofs. 

Related: Gambrel Roof: Advantages and Disadvantages

How to keep water from under shingles on a skillion roof

When it comes to the skillion roof, an extra layer of waterproofing element under the shingles could help in keeping the water off it. For this, you need roofing felt underlayment. One can use roofing felt paper or roof tar paper. Install it in between the deck and the shingles to keep water from under shingles on your skillion roof. 

How to beam skillion roof

For this process, you have to install the beams horizontally at a 90-degree angle relative to the rafters. The beam’s main function is to provide support for the rafters and create a steady roofing frame. Here is a visual of how to beam a skillion roof. 

What pitch is preferred on a skillion roof for a shed?

Whatever the roof type you will use for a shed, the recommended roof pitch for it would be 10-15 degrees and a secondary pitch of 5 degrees if necessary. For larger sheds, an increase of 0.25-inches per 12-inches of run is also advised. 

How to insulate a skillion roof

Skillion roofs with concealed or exposed rafters are insulated differently. For skillion roofs with concealed rafters, the insulating material should be at a 25mm gap relative to the rafters. For those with exposed rafters, installing the insulating material should be above the ceiling’s lining. Aside from the 25mm air gap between the insulating material and the rafters, an additional roofing underlay should also be in place. 

Here are other ventilation tips for skillion roof insulation: 

  • Install a fascia vent on top of a timber of metal fascia on the skillion roof. 
  • Install an appraised vented batten on top of the wood or metal purlin. 
  • Install an eaves comb filler to prevent bird nesting on your skillion roof. 
  • Install an apron vent under the skillion roof’s barge detail to allow good circulation of warm and moist air. 

Conclusion

skillion roof house plans advantages disadvantages

With all things considered, skillion roofs are here to stay. Aside from proving to be an economical choice especially for modern design homes, it is also easier to construct, versatile, and comes with more advantages than cons.