Pergola construction details

Pergola construction details

April 16, 2013; 14:28 pm by Neal Adamiak

We have received a lot of great questions and interest as to how we designed and built this pergola (see photos). This pergola design "gives the appearance" that it is "connected" to the roof structure. Here’s an explanation about how this pergola was made and hopefully inspire you to create a similar structure for your home.

The initial concept came from interior designer, Anthony Catalfano. for whom this home was built. He wanted to make the dining room space (inside behind the patio doors) and ceiling beams to continue out to the patio. The design intent and architectural theme of the house was to make a distinct connection to and complement the surrounding landscape and picturesque views of the neighboring Maine seashore. Anthony wanted the dining room to have the ability to open up (via the large French doors) and extend the "indoor space" out onto the patio for seasonal entertainment purposes.

With the client’s direction and vision in mind, Woodmeister went to work to try and come up with a way to make it look like the pergola was extending out from the dining room. We also needed to figure out how to make the pergola connect to the roof without creating potential complex flashing details / water infiltration issues inherent with typical exterior to interior wood framing connections. "Cantilevered" framed decks structures are a great example where water infiltration is often a problem.

To avoid water infiltration, the pergola beams were designed and detailed to be "set off" the roof by approximately ½" from the roof shingles with stainless steel "T" shaped roof clips. This construction detail gives the appearance that the pergola beams are built-into and continuing into the "beamed" ceiling of the adjacent dining room inside the home, and, from the inside of the dining room, it appears that the beams continue to the outside pergola patio.

The bottom of the "T" clip is fastened to the roof and flashed (on top of the ice and water shield substrate). This ½" offset-clip detail allows the rainwater to runoff between the top of the roof shingles and bottom of the pergola beam.

You can find these roof clips with most "roof snow guard" manufacturers. The stainless steel clip is mortised into the center of the beam end, bolted and plugged then finished and painted to hide the bolt connection holes on the side. The exposed ends of the cut beams (cut to be parallel with the roof slope) also needed to be properly coated, primed and sealed for water exposure.

To View a PDF of this Pergola Construction Detail [CLICK HERE]

We built this pergola with cedar to match the material of all the other trim on the exterior. However, it would be just as favorable to have the beams made with a composite material for less maintenance — especially for coastal homes — that are often exposed to extreme wet weather conditions.

I have included a detail sketch and a couple of photos as a visual reference.

Good luck on your pergola projects!


Neal Adamiak | February 26, 2014 | 16:30 pm

Hi Sheri,

This is a tough question to answer! The pergola details presented here were specifically designed for roof materials that are relatively flat, such as the wood shakes used in this example. You might be able to find or make a deeper custom ‘T’ clip and fasten the pergola beams in between the clay tiles. Having used the flat roof materials, we were able to keep the bottom of the pergola beam close to the face of the shingle making it look like the pergola beam was “coming” out of the roof. It might be tougher to achieve this look with the clay tiles.

The architectural details would need to be carefully worked out.

Sheri | February 24, 2014 | 17:48 pm

How would you attach this to a Spanish "S" tile roof?

Noah Simmons | July 3, 2013 | 1:10 am

Mr. Komenda,

My name is Noah Simmons and I live in Central Arkansas and currently helping a buddy build a Pergola at his residence. We have set three 14ft 6×6 treated post about 8ft apart at a depth of 24" with approximately 5 bags of quik-crete to each post, so they are well supported. The next step is to actually start the construction of the Pergola and the goal is to attach it to the roof as shown in your pictures. I plan to place the beams on 16" centers spanning approximately 20′ or so. I am concerned about how to attach the beams to the roof without causing leakage from securing the beams.

I understand the "T" clip concept and know that I can have them machined for the project, the question is would I need to have a roofer come in and prepare the areas for the beams with the flashing as I am not a roofer and really not much of a construction worker but I can figure things out pretty quickly. Any guidance or other options you can provide me would be great. I know the finished height of ceiling will be 9′, I hope that gives you some sort of idea. I cannot attach a 2×10 to the brick because there is not room for one and the head room will not allow for it. The only other option would be to set three more post on the patio which would cost my buddy about $300 more in material.

Thank You

Pergola construction details

Noah Simmons

Rosemary Walsh | May 20, 2013 | 16:40 pm

"However, your contractor should be able to advise you for your particular pergola. Ultimately, the "T" clip is just one way to attach the beams to the roof."

Chris, I was fortunate in that I was able to talk with Neal Adamiak about using the T clips. Previously thought we’d tie into the roof rafters for the pergola beams. Several people have cautioned me about possible/probable water problems if the integrity of the roofing is messed with. Simple me was thinking that flashing, properly installed, would mitigate that risk. Any advice on how to BEST attach the beams. They will be 6×6 cedar most probably, because they will be spanning about 16′.

Again, appreciate your advice and counsel.

Chris Komenda | May 20, 2013 | 15:47 pm

Hi Rosemary,

It’s hard to give you an assurance on the "T" clip, or whichever fastener you decide to use, without knowing the full scope of your project. We used 1/4" stainless steel for our project. However, your contractor should be able to advise you for your particular pergola. Ultimately, the "T" clip is just one way to attach the beams to the roof.

Rosemary Walsh | May 20, 2013 | 14:32 pm

Chris, thanks for this link. I know absolutely nothing about snow guards (live in GA) and couldn’t figure which of the products you thought would work. Have a composition shingle roof. Don’t know what the membrane is that’s shown mounted just above. Also, these are aluminum or brass and I need reassurance that this would be a strong enough metal. I thought the stainless steel custom T connectors were approx. 1/4" thick (sorry, don’t know what gauge that translates to).

So many questions, so few contractors interested in my job. I’ll find the right one though. He’s out there somewhere waiting for my call.

Chris Komenda | May 20, 2013 | 14:18 pm

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