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Are All Decks Made to Support a Roof?

One of the best outdoor living spaces you can have in your home is a deck with a roof as it keeps you dry during wet weather and provides shade during summer. Besides its functionality, it can also increase the aesthetic appeal of your home making it a worthwhile investment. The best time to build a roof over your deck is when laying the foundation of the deck itself. However, safety concerns may arise in a situation where you add a roof over an existing deck. This article looks at whether all decks are meant to support a roof and what you need to consider before adding a roof to your deck.

Safety Concerns about Adding a Roof to an Existing Deck

A regular deck is designed to support a particular amount of weight per square foot. However, the added weight of a roof on a deck requires more support from the foundation to enhance its durability. Not all decks are meant to support a roof as the foundation of the structure may vary depending on the intended purpose of the deck. Some roofed decks may require large footings and even additional footings for extra support. Adding a roof onto an existing deck that was not designed to bear the weight of a roof can put everyone at risk as it can collapse at any time. If the deck was originally designed to support a future roof then you will not have a problem putting up a new roof over the existing structure.

How to Build a Roof over a Deck

The best way to build a new roof over your deck is to remove the original foundation and enlarge it so that it can accommodate the weight of the roof. The posts should not stack within the span of a beam but directly above a support post below. The deck floor frame should be at least as thick as the whole cross-section of the post located above and below. For instance, a 1.5-inch thick rim joist cannot support a 3.5-inch thick post above. It is important to install blocking adjacent to the rim joist.

Alternatively, the roof can be designed independently from the deck if you intend to replace the deck below the roof or you want to avoid modifications to the existing deck below. This means that new foundation piers can only be sized and installed with the roof in mind. No matter the situation, it is important to consider the weight of the roof to guarantee the safety of people who will be using the deck.

Factors to Consider Before Adding a Roof to Your Deck

  • The Structure’s Foundation

A deck’s foundation plays a significant role when installing a roof over the structure. It is not recommended to install a roof over your deck if the initial foundation was not designed to support a new roof. Some roof types may require an additional footing at the center of the side rim to transfer the rafter loads or truss to the footings. This is necessary because the roof’s framing is perpendicular to the framing of the floor.

  • Type of Deck Roof

Some types of roofs that can be installed over decks such as the shed, gable, and hip roof. A gable roof is the most common and blends well with various types of architecture. It projects along a ridge at the center forming a triangular shape that overhangs the enclosed space. It facilitates proper drainage of rainwater and snow, unlike flat roofs. A shed roof starts at the exterior wall of the house and ends at the support posts forming a single sloping surface. A hip roof slopes more gently with a solid compact appearance but requires a more complicated support system.

  • Material Costs

It is important to discuss the cost of materials associated with each type of roof as it can affect your preference over other designs. The costs may vary depending on the roofing material, the architectural design of the roof, and labor. You can always inquire about the estimates and overall impression of the selected design to settle on a deck that suits your style and preferences.

Not all decks are meant to support a roof as their foundations are laid out differently when during construction. Building a roof over an existing deck without considering the durability of its foundation can have a huge impact on the safety of the entire structure. If it is necessary to have a roof over a deck that was not originally designed for such weight then you should consider installing it independently to avoid modifications on the existing deck.