Gimme Shelter
If you need to end a drought in Colorado, take the gutters or the roof off a house. Deconstruction always brings on a downpour. Our May weather highlights the need for proper gutters, downspouts, grading, and sub-surface drainage. Mother nature constantly reminds us that the primary function of architecture is SHELTER. 
Our restoration and addition of the mid-century modern T. Maslin House (see previous post: Modern History) illustrates the balance between function and preservation.
The new owners of this project know that to build a solid house, they have to spend money on some hidden, unglamorous things. Some of these items are waterproofing on foundations, perimeter drains buried deep around the building, roof sheathing, and insulation. The remodel of a house older than 15 years demands upgrades in energy conservation and comfort. But the needs to heat, cool, and provide natural light, often come into conflict with the need to preserve a building’s exterior.
CHALLENGE:
Along with making the house sustainable, the homeowners and the Landmarks board want to preserve the outer appearance, including the façade’s fixed transom glass and thin roof structure that are characteristic of the style.
The City of Boulder requires a HERS 60 for this house (equals 40% better energy performance than a standard new house built today). Among other things, this means putting R-49 insulation in the roof (14” of cellulose)…but the rafters are only 2×6 with transom glass tight against the rafters.
OUR SOLUTION:
The transoms and the slender eaves prevented us from making the roof deeper. We devised the detail below.
- Fill 2×6 rafter space with 3”+ of closed cell spray-on foam insulation (R-19).
- Add 4” polyisocyanurate board above the sheathing, tapered at the eaves to maintain the slim 2×2 fascia.
- Install semicircular gutters.
In between spring storms, the contractor peeled away years of roofing build-up and clunky gutters to restore the eaves to their original look.
NEXT: high-efficiency windows come in this week. Click here to read more about the construction progress of this project.
Juana, I would love to have some copies of photos of the eave detail for Landmarks so we can show folks that it is possible to add insulation to the exterior of the roof without changing the fascia profile. Nice job.
Mark,
Thank you for your comments. I will send you photos via email.
Juana
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