Dear PoP – Getting a Roof Deck

“Dear PoP,

It’s that time of year when it would be great to have a rooftop deck on which to spend some quality time. Luckily, my condo building is exploring the possibility of putting one in place. I was wondering if any readers have any experience working with local contractors to design and build a roof deck and what issues are important to consider when putting one in place. Any advice on selecting a contractor or on what would be a reasonable cost to build one would be much appreciated.”

Great timing! Another reader just wrote some tips about getting a roof deck:

“Dear PoP,

Roof Deck Instructions

1. Own your home or have condo permission to build

2. Contact an architect and tell them your thoughts, ideas and plans, they will draw up the deck, have it approved by a structural engineer and obtain the permits for you through DCRA

3. Your roof top probably will not hold the weight of a deck as is, so most decks are built from parapet wall to parapet wall. (brick walls) If you share any wall with a neighbor as most row houses do you will have to have written permission from the owner of that building for you to build on the wall. The engineer will pull a plat of your property to see who owns what.

Continues after the jump.

4. Depending on how DCRA Feels the day you apply for the permit they may also ask you to get permission from any other surrounding neighbors who may or may not have a concern about a roof top deck being added to the neighboring property.

5. Once the plans are complete and you have a permit from DCRA you hire a builder of choice, most any builder can build the deck, the details are in the engineer you used who did all of the legwork with the drawings and permit. When in doubt ask for suggestions from your engineer.

6. Consider how the contractor will get the wood up to your roof, consider having your roof covering updated when building the deck as it would be harder to do so later if the covering is getting near the replace date, consider where the contractors will park and where the lumber will be unloaded and stored. If you do not have roof access (i.e. a door to get out on your deck and stairs) then that will increase the cost obviously.

A good sized deck will run about 8,000 for a standard design construction including materials, the engineer will run about $1500 and the permits and plat fees are usually under $300

DC code says no gas grill with a propane tank can be located on any roof top deck, and must be 10 feet from any structure, you can however have a natural gas grill hooked into your home gas line (professionally done) or an electric grill.

Enjoy your deck!”

56 Comment

  • Am currently looking to do one (plus the access to get to the roof). Would be greatly appreciated if any good builders can be recommended.

  • Follow up question … does anyone belong to a condo association that has amended (or initially had) language re: the responsibility of an owner for a roof deck when it is their own deck and only they have access? For example, language related to what happens if the common roof needs repair, maintenance obligations by owner, and so on. If anyone has an example of standard condominium clauses on this topic, I would GREATLY appreciate seeing an example. Many thanks!!!

  • It is my understanding that virtually no roof decks actually get approved for installation by DCRA? Can builders and owners please share their experiences?

    • I’ve heard horror stories from friends about it taking forever to get the permits… Many of them simply gave up.

    • alternatively, can folks who built an illegal roof deck share their experiences?

      • Well, there is the house on 10th St NW. PoP posted a photo of a crane (I think) putting the 2-story spiral staircase into position. Several people commented on how the roof deck was on top of the neighbor’s chimney and how a 2-story spiral staircase was asking for trouble. A guy from DCRA posted, asking for info on where this was located, because it was in violation of several code provisions.

        A year, maybe two, later, that roof deck is still up, it’s still on top of the neighbor’s chimney, there’s still a 2-story spiral staircase–basically, nothing has changed. They certainly didn’t have to tear it down. I can’t say for sure they haven’t been fined, but it looks like the consequences have been pretty small.

    • I got a rooftop deck approaved.

  • We don’t have a roof deck, but there are two buildings within a stone throw of mine (in Adams Morgan) – one is a coop, I think the other is a condo – that have installed (legal) roof decks in the past five years, so I suspect what you have heard is inaccurate.

    Of course, I don’t know how long it took the Associations to get the paperwork through, but it does happen.

  • Oftentimes the access to the roof is more of an issue than the deck itself, especially if you’re in a historic district. Plus there are rather arcane zoning restrictions on rooftop structures that might affect the access point. Architects are often the best resource for navigating these issues, not builders and engineers.

    • My understanding for historic areas is that basically, as evident from the plans, the roof deck will not be visible when looking at the front of the building from across the street. Then again, in my historic neighborhood there are a number of roof decks visible from such pespective.

      • The sticky wicket is if you want anything higher than a roof hatch that’s flush with the roof. More elaborate structures may get torpedoed by either HPO or Zoning. And, as you said, sight lines and “viewsheds” are critical.

    • The access is something to think long a hard about. I saw a house in a historic neighborhood that had a roof deck, and while the deck itself was awesome the tradeoff was a very scary ladder installed in the upstairs hallway of the house. It was extremely awkward and ruined the flow of the space.

      • If it had a ladder, then I can’t imagine it meets code or was permitted *properly*.

        • I mean a ladder in the sense that it was nearly vertical and had slats instead of steps. I’m pretty sure it was legal…

  • That sounds amazingly high for the engineer’s plans. I had a structural steel beam put in my basement and it was less than $1k for the plans. At $150/hr who takes 10 hours to design a roof deck? It’s the same load and span tables you’d use for the interior floors. The only thing even remotely complicated is the stairs.

    2×10’s or 2×12’s 16″ o.c. Done. I’m amazed if that’s the going rate.

    • Well,

      Its not the same as an interior floor at all. Don’t see many interior floors designed for windshear or snowload.

      And it isn’t the time he is charging you for, its the PE Stamp on the plans. The PE is not only hard to get but makes the engineer civilly and in many cases criminally liable for something should it go wrong.

      • The weight of the wood plus ample tie downs is sufficient for wind. Snowload is just a calculator addition which means you go with the 2×12’s for any significant span. Go look at a standard deck and you never see a joist larger than 2×12 and it’s subject to the same snow loading conditions as a roof will be –snow falls down from the sky the same everywhere.

        It’s not 10 hours worth of work for a PE of any quality unless it’s your very first time. A structural PE is $150/hr.

        • Hehehe…yea, “OK” there ace. Whatever you say.

          And as I stated above, it isn’t the time he is charging you for, its the stamp.

          Frankly, back in the days before I had teams of engineers stamp things for me, I wouldn’t even get my stamp out of my desk drawer for less than $500 bucks (on top of the hours spent on the task. All the schooling, licensing and liability doesn’t come for free,but what am I thinking…you are the expert 🙂

          Signed – Structural PE

          • So you’ve been overcharging for 20 years. Good for you.

            My guy is a licensed PE, with a DC and VA stamp and his plans were approved by DCRA in one trip.

          • You’re on a roll recently. You need to get more sleep.

    • I disagree. As mentioned in the original post, in most cases you just can’t build a deck on top of the roof, you have to build a support structure calibrated to hold a much greater weight load than the average roof – which, obviously, was probably built with no plan of having more than one or two people occasionally standing on it at any one time.

      The specs will also have to meet whatever standards are set by the property’s insurers as well.

      A beam in a basement is not really a comparable job.

  • We got an estimate of $30,000 to $40,000 for a roof deck including the roofing beneath it. $8,000 seems crazy low, though I guess if you don’t use an architect or live in a historic district its possible.

    • $30k! You were getting taken unless you have a 4000 sq ft roof.

    • Let me guess: was that from Maggio?

      • no it was a construction cost estimate from my architect.

      • how does maggio make money? They made a wildly high quote for my roof replacement.

        • Because there are a lot of old fuddie duddies in Cleveland Park and Potomac with more money than brains who have no idea what things cost and think nothing of it to throw down 30K on a roof.

          With their prices, you only have to get a few fools a year to hire you.

    • I’ve never gotten estimates, but that was exactly my thought. If it only cost $8k, wouldn’t the entire city have roof decks?! I’d build one in a second at that price if I owned a rowhouse.

  • “DC code says no gas grill with a propane tank can be located on any roof top deck”

    So, I wonder how countless bars get away with those free standing heater towers on their rooftop decks? I know it’s not a gas grill per se, but it’s essentially the same thing: a big pot of combustible propane (or other explosive gas) with the wick lit.

    Not disputing your citing of the DC code, just wondering about what makes these things different (ie, somehow less dangerous) than a gas grill. Powerful bar/restaurant lobby, maybe?

    • Or we could go with a sprinkler system or some other fire prevention installation.

      • but then why allow one and not the other, is my question. (regardless of fire prevention system)

        • Oh, I agree completely that they’re probably indistinguishable in terms of risk unless there’s some additional safety feature designed into them.

          I was under the assumption that the no grill rule could be overcome with the addition of a fire control sprinkler.

    • it’s the ash that is dangerous. with gas grills, you don’t have to worry about that, at least. less of a problem in days when we had ash cans.

  • I am quite surprised at an $8K quote. I have gotten several quotes (at least 3) for a roofdeck for an average sized rowhouse in Dupont (in historic district), with lighting and water access, and built-in bar, in the $30k -$50K (including architect, engineering, and design fees). Now, this would be with all correct permits and by licensed and insured builders.

    Pretty much the rule of thumb is that you just should not be able to see it from the street. They do approve these things, as one is being put up on my street right now.

    Also, I have one correction to the “roof deck instructions” above. You do not actually need your neighbor’s approval to build on the joint retaining wall. You can only use half of it and you just need to notify them of the proposed project. They may be able to challenge it, but you do not need their approval.

  • Here are a couple of things I learned in the process of adding a 785 sq. ft. deck to our suburban manse:

    Start the process of getting engineering, drawings, permits, etc. over the Winter – that way you’ll (hopefully) have your contractor ready to go as soon as the weather gets OK for him to work.

    See if your GC will pass his contractor’s disount on lumber on to you, instead of marking up the lumber as a service to you. Ours negociated the price w/ his supplier, then we called them and put it on our credit card.

    Don’t forget the cost of lighting and furniture. Both are quite expensive for the good quality, durable stuff you will want if the deck will be shared among residents of the building.

  • I just got a permit for adding a roof deck. It took awhile, the city had some concerns, but my builder got it, probably took around three months, maybe a bit less. Basically, I had to provide a copy of a certified letter to neighbors explaining what I was doing, a certificate of occupancy for my building, and photos of neighboring buildings (which showed that many also had roof decks, and showed how you wouldn’t see my deck from the street). That plus the plans, and they eventually approved it.

    Now I am just trying to finalize revisions to my condo documents re: ownership, maintenance, repairs, and so on (see my comment above, any insight would be MUCH appreciated :)).

  • and additional friendly reminder or two…make sure the building does not have a conservation easement. if it does, you will have to have permission from the historical foundation/group that holds the easement. our neighbors did a roof deck last year for just under 30K. also there is a law that regulates the exterior living sqare footage to the lot. inspections will be done by the city as the deck is built. good luck.

    • I do not believe there is a law regulating exterior unroofed living square footage on a lot. There are FAR (floor area ratio) regulations but they apply to interior only.

  • Hey, you can see my house from the roof deck pictured. The deck is amazing, I watched it go up with envy. I have been curious about how to get this done legally, as well. The access point is the big question mark, because the city wont let me build stairs anywhere outside.

    • Hello neighbor : )

      To do it legally just get a permit from DCRA, to get a permit from DCRA, hire and architect so they can tell you what you need to do and they will make sure it is done by code. They will get the permit for you once you have met all the requirements.

  • Now that all of the questions are in, I will take a moment to answer them. I just went through this process so I speak from experience, not from my A#* : )

    When I first started my research for a roof deck there was no information anywhere, nobody could help on the blogs and nobody had recommendations. I wanted to offer my experience for others who ran into the same problem, I hope this helps some. (If you remember one thing, start with an Architect)

    1. This deck was done with a permit and with a good bit of quality, I did not want any trouble when I was done so I jumped through all the hoops to ensure it. I also supervised the construction process all the way through. (Construction background experience here, if it were a deck on the ground I would have done it myself, but on the roof, who wants to fight with getting it all up there?)

    2. I meant to say Architect where I said Engineer in step two, thanks for the correction. The architect will draw up your ideas, get structural approval from a structural engineer and they will work with DCRA to pull the permits for you, that is WELL worth 1,200 – 1,500 bucks, and as another user mentioned they are legally responsible for any issues that arise later if there are any issues such as a deck collapse etc. This span was 22′ across so beams had to be fabricated for the load / span.

    3. Consider where you live, a Deck in Eckington is not going to have the same issues / problems as a deck in Dupont for obvious reasons, think about it. Nobody cares in Eckington and parking is not a problem, in Dupont EVERYBODY fights everything and you have no parking for construction and lumber etc. I had the perfect situation, I am not in a historic district, I did not share any walls with any other building, I had direct roof access via an existing door and the location was built with a roof deck in mind. If you don’t have any of that, be sure to add funds to your deck savings account and headache to your permit process.

    4. Yes DCRA approves roof decks all the time, every single project is unique though so there is your answer. The more issues you have the harder a time you will have. I shared no walls but I still had to get written approval from neighbors before DCRA would issue a permit. DCRA will TELL YOU what DCRA can do, and you can cry and moan and never get a permit, or you can do what they ask and get your deck. Feed the dragon and the world becomes simple.

    5. Estimates. An estimate in Eckington will not be the same as an estimate in Dupont for obvious reasons. Any contractor who sees someone living in Dupont as someone who can and will pay more so expect your estimate to be higher just because of where you live. Do your math. Go to home depot after you get your drawings and price it yourself, knowledge is power. Most contractors are used to dealing with city people that know nothing of construction so you take what is offered. My deck was a single level 16 x 22 and the materials, wood and connectors were just under $3000. The special order balusters and post caps were about $800. Delivery was about $150 for two deliveries. The rest was labor and it came in at about 8,800 total. If you have a multi level deck, or decking design on a 45% angle or choose to use the PVC or TREX fabricated wood or add water and electricity and a hot tub etc then you must expect to pay more. Grab a big ole bucket of common sense while you are at Home Depot, it is on isle 7. : )

    6. Condo questions, If you are building for your own use, and the building is set such as to allow this (i.e. the access to that area is only through your unit) then you start with your Condo docs. The condo docs will say what must be done in order to make a change to the building. Those can include a vote, and proof that what you will do and that it will not harm the building in any way. Using an Architect and Structural Engineer would be the way to go here so they can present that information. Then you have to do whatever your docs say, i.e. get the board to approve the change with the information presented. In this situation the way it was handled is the condo is still responsible for any upkeep of the roof itself since the deck does not touch the roof, the deck actually protects the roof and this deck is high enough above the roof for good access to make any roof repairs at a later date. The roof is also brand new. The owner of the deck is responsible for any upkeep and repairs of the deck itself. The deck is for the sole use of the unit that provides the access and will be sold along with the unit in the future as being part of the unit. The building insurance covers the deck as a person could jump/fall from the deck just as easily as they could from the roof itself. Common courtesy also was extended to the rest of the condo neighbors as in there will be no loud parties on the deck, any grill will be electric, and any furniture is heavy teak wood so there will be no damages from anything blowing off the roof deck in high winds and the deck design was created to accent the building’s architecture adding visual appeal to the building itself. So start with your condo docs, then make friends with the board, and good luck to you!

    7. Finally there is the DC code about grills, and questions about why some people are allowed heaters. Common sense says people alllllll over DC do things they are not allowed to by law, but if you are going to follow the law, here it is.

    308.1.4 Open-flame cooking devices and Liquefied-petroleum-gas-fueled cooking devices.
    Pursuant to the DC Fire Prevention Code Outdoor Grill Safety Amendment Act of 1990, grills, charcoal burners, other open-flame cooking devices, and LP-gas burners with tanks shall not be operated on rooftop terraces, balconies or within 10 feet (3048 mm) of any dwelling.
    Exceptions: 1. Natural gas grills.
    2. Any common area within an apartment complex designated by
    the landlord, management company, or owner for outdoor grill use.

  • Anyone want to guess or share the cost of pop-up plus roof deck? I remember past PoP postings as saying popups cost $100k+ but $8k for a roof deck makes it seem like a popup could be cheaper, no? And, if just doing a roof deck, how much do stairs cost?

    • Well a roof deck is simply pressure treated wood, a pop up is framing, sheet rock, doors, windows, siding, roofing, rafters, paint, etc… etc…ect…

    • We have a third floor that we would like to raise the ceiling of by 1-2 feet, so not quite a full popup but a completely new ceiling and some additions to the exterior walls. Architects and builders have quoted us around $150K to do that and rebuild the roof deck. This price estimate included a new bathroom on the top floor, several skylights, etc. I’m certain you could do it for a lot less but if we are going to go through the trouble it will be done right. Project currently on hold due to graduate school.

  • This is among the most helpful posts ever. I’m sure lots of us who own rowhomes have, at some point, considered it, and end up with a handful of hearsay and misinformation for our efforts before we give up on the idea. But this … assuming some of the comments and the information in the initial post are not from BS artists … this is good stuff.

    I echo Styglan1’s call for similar information on pop-ups.

  • Ahhh you give them Deck info and they ask for Pop-up information, will this madness ever stop! : )

    All of the info was true to course. I believe in paying it forward, glad to help someone else.

    The architect I used was Martin Barnes
    “martinbarnes AT”

  • My addition would be to budget in extra money and go with Trex or similar decking material. Pressure treated lumber isn’t supposed to be sealed until it is weathered, but mine skipped weathering and went straight to trashed. Replacing with trex (and hauling 50 10 foot boards up 3 flights of stairs winding through narrow staircases) sucked.

    Roofdecks get extreme heat beyond what ground level decks see so just go with trex or equivalent.

    Also… carpenter bees suck and will ruin much of your deck enjoyment as they hover in your face. I have no problem with them on our ground level decks, but roof deck use requires alot of bobbing and weaving to avoid those bastards.

Comments are closed.