Transform your living space with a modern rooftop deck! Picture an outdoor kitchen, lounge, and entertainment areas layered with greenery—an oasis to escape city life. Building a new roof deck or expanding an existing terrace comes with some design and logistical considerations we’ll cover in this post.
Are you on the top floor of a loft building, or does your house have a flat roof? Do you want to take advantage of that area to increase your exterior living space? Then, you might want to consider adding a roof deck and penthouse above your existing living space. However, before you start laying the deck boards, several factors need to be considered to determine if your project is feasible. Moss assists with the design and architecture of the rooftop space, along with addressing the logistical challenges that come with it.
The roof and screen design concepts, along with the renderings below, were shared with a client who approached us looking to expand their living space.
Renderings for full rooftop entertainment and kitchen/lounge design
Modern Rooftop Deck Structural Support
Perhaps the most consequential factor in determining if you can build a roof deck or expand your terrace is not what you can see—it’s what you can’t see. Outdoor spaces like decks and terraces must meet the code minimum load requirement (a fancy term for how much weight they can handle), measured in PSF—pounds per square foot. Most existing roofs weren’t designed and built to support this load. That means you’ll either need to reinforce the structure below or add a supplement structural system to carry the weight. This has major design implications and needs to be investigated early in the planning process.
Decking Below and Roof Cover Above
After the main structure is built, the actual decking/walking surface must be designed. This can be constructed of a wood product, such as cedar, black locust, or ipe, or a paver-type system. The pavers are typically installed over a grid of pedestals so water can drain through and under the pavers. The most common pavers are made of concrete, which is heavier and more expensive but not subject to wind uplift loads. The other option is ceramic, a lighter, less expensive material but subject to uplift.
Most decks, balconies, and terraces would not be hospitable if they were left open to the elements like the sun beating down in the summer or rain falling from above. A roof, overhang, awning, or trellis are the best options for achieving some protection from the elements. These can be constructed like a typical roof (wood joists and roofing material) or be built from wood or even powder-coated steel or aluminum, which is the most resilient option that requires little or no maintenance.
Isometric sketches and construction progression for a rooftop deck spanning half of a flat roof area
Outdoor Kitchens
The only thing better than being able to comfortably have dinner outside is to cook outside as well. But some advance planning is required to make this happen. The first thing to consider is what you’re looking to accomplish. Just a BBQ grill? A smoker? Pizza oven? And how about the convenience of a sink or stovetop? Any of these options require utilities to be brought to the Kitchen area. And, if you are in a cold climate, you should think about how to shut down during winter.
Cabinets are also another consideration. We prefer stainless steel and often use Kalamazoo Kitchens, which fabricate custom cabinets and appliances. Lastly, countertop material is a key consideration for outside conditions. A solid stone, like Bluestone or Limestone, is relatively easy to work with and can be cut on-site, but it can be more porous than an engineered stone like Caesarstone or Dekton. Lastly, if you are considering a fireplace there are various manufacturers and models, but do ensure that the model you select is made for exterior conditions.
Project Examples:
West Loop Chicago – Enclosed rooftop penthouse with outdoor lounge spaces
We look at sun and shade paths, and prevailing winds for all of our projects to determine the most desirable site orientation.
Sketch and renderings created during the schematic design phase illustrating a rooftop penthouse design
Lincoln Park – Rooftop penthouse addition
Here’s an example of a rooftop penthouse addition we designed for a three-story townhome. The original rooftop had a tricky pop-up door that made access a hassle. We designed a stair extension and created an indoor lounge area so our clients can soak up some vitamin D sun rays and then step outdoors for total immersion into the exterior lounge space.
One of several sketches created during the initial design phase: construction progress, night views, and finished roof deck with an overhang to protect against sun and rain
How to Design A Modern Rooftop Deck and Outdoor Kitchen FAQs
How much does an outdoor kitchen cost?
Many variables exist, but stainless steel cabinets can range from $400 to $1,000 per linear foot. Appliances, grills, and smokers range from $2,000 to $5,000 per appliance. Pizza ovens can range from $1,000 for a tabletop model, such as Ooni, to $10,000 and up for a custom Napoli-style masonry wood-fired oven, like a Marra Forni or Forno Bravo model.
Can my existing roof support a rooftop deck?
Probably not. We would need to investigate if it is possible and what the reinforcement system would look like.
What are some quality materials I can use for a modern rooftop terrace?
The least expensive but least resilient are wood species made for exterior conditions, like cedar or ipe. Stainless steel, powder-coated aluminum, and stone are more expensive but more maintenance-free options.
Can I build a roof terrace above my loft condo or apartment?
Aside from the logistical and structural considerations, your building’s Homeowner’s Association may be the final decision maker on whether you can add a penthouse or roof deck. There might also be language in the condo bylaws that expressly prohibit or allow roof decks.
What are the code considerations for a roof deck or penthouse?
They are mainly Zoning Ordinance-related issues. The building’s underlying base zoning likely limits the allowable square footage and height limit. There are exceptions to those requirements if the penthouse and roof deck are located appropriately and are limited in size and height.