Thermally Broken Roof Framing

The builders of the 2018 FHB House illustrate how unique hardware from Maine Deck Brackets helps them to reduce thermal bridging and leave room for exterior insulation.

By David Good

The finished roof over the first story of the California house will be one sleek, continuous plane when it’s done. However, we had to come up with some unique framing details to keep that clean look while also reducing thermal bridging.

There are several roof areas that are not over conditioned space: the porch, the north overhangs, the breezeway, and the master-bedroom balcony. This created the need for several unusual transitions across the roof framing. Because we want the exterior insulation to wrap continuously up the walls and over the roof, we fastened the various ledgers and overhangs to the walls at these transitions with Maine Deck Brackets. The I-beam-shaped aluminum brackets provide a standoff of 4 in. from the framing, which is exactly equal to our exterior Rockwool mineral-wool thickness on the walls, allowing the insulation to slip behind these framing elements on its way up over the edges of the roof.

The aluminum standoffs hold the ledger 4 in. off the building to reduce thermal bridging. This ledger is for the porch roof on the west end of the house. A strip of the water-resistive barrier (WRB), Delta Vent-SA, is run at the top of the wall before bolting the Maine Deck Brackets in place so that there’s a continuous air barrier.

With the ledger in place, the roof of the large covered porch is framed with Trus Joist TJIs.

The overhangs on the north side of the house are also attached with Maine Deck Brackets.

Once the overhangs and porch roofs are framed, the crew integrates the air barrier/WRB with the strip that was installed behind the ledgers.

This view shows the first-story roof over the mudroom and first-floor bathroom (covered in black Delta Vent S underlayment), and the plywood sheathing of the breezeway roof to the right. It’s easy to see how the height of the ledger attached with the Maine Deck Brackets is 5 in. above the roof over the conditioned space of the house. The two roof surfaces will be in plane when 5 in. of exterior Rockwool insulation is placed on top of the Delta Vent S.

More from FineHomebuilding.com

Fine Homebuilding Recommended Products

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

Leather Tool Rig

This is tool rig is heavy duty, professional, and well-thought-out for tool storage — plus it can help reduce fatigue throughout the day.

Buy at Amazon

QuikDrive PRO300s

Whether you're installing floor sheathing or decking, this tool will keep the installer upright, putting less stress on workers while saving time and energy.

Buy at Amazon

Caulking Gun

It's important for any insulator to have a good caulking gun for air sealing or adhesives, and this one features a revolving frame that makes orienting the tip a breeze.

Buy at Amazon

View Comments

Deleted | Jan 13, 2019 03:37am | #1
“[Deleted]”
AshleyKLemelle | Jan 13, 2019 03:38am | #2
Great roofing

Log in or create an account to post a comment.

Become a member and get full access to FineHomebuilding.com

View All

Fine Homebuilding House California 2018 Sponsors

Donating Sponsors

Up Next

Video Shorts

Featured Story

Duhumidifying With Heat-Pump Water Heaters

Dehumidification is listed as a selling point for HPWHs, but are they actually effective at lowering humidity?

Featured Video

How to Install Cable Rail Around Wood-Post Corners

Use these tips to keep cables tight and straight for a professional-looking deck-railing job.

Discussion Forum

Highlights

Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

View All

Fine Homebuilding Magazine

Fine Homebuilding

Follow

Get home building tips, offers, and expert advice in your inbox

Membership & Magazine

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

California 2018

Thermally Broken Roof Framing

The builders of the 2018 FHB House illustrate how unique hardware from Maine Deck Brackets helps them to reduce thermal bridging and leave room for exterior insulation.

Navigate the Build

Behind the Build

View Comments

Log in or create an account to post a comment.

Become a member and get full access to FineHomebuilding.com

More California 2018

Fine Homebuilding House California 2018 Sponsors

Donating Sponsors

Up Next