Doghouse Dormers: Framing From the Ground Up
Assembling parts on the ground and cutting the roof at the last minute provide a low-stress route to a high-value project.
Synopsis: Doghouse dormers can be the perfect accent to many house styles. Rhode Island builder and Fine Homebuilding contributing editor Rick Arnold shows his technique for cutting and assembling doghouse-dormer parts on the ground to minimize rooftop assembly time — and also to minimize the duration that a house’s interior is open and at risk to the elements. Arnold highlights the process with details about how he calculates a precise roof pitch, then uses the Pythagorean theorem to determine dimensions for framing members and dormer parts. Included are sidebars about dormer design and the California valley that Arnold uses when installing a doghouse dormer.
One of the most popular ways to open the dark, cramped upper level of a house is to build one or more dormers. From a homeowner’s point of view, these small additions can increase curb appeal and create more-hospitable living space in the top level of a house. From a builder’s point of view, dormers concentrate almost all aspects of residential framing into one small package. Like any building project, the success of constructing dormers depends on precise calculations, careful planning, and some smart assembly work. Trust me, the last thing you want is to be on the roof trying to figure out why the wing wall won’t fit while a rain cloud hovers overhead, waiting to take advantage of that big hole in the roof.
Over the years, I’ve built a number of dormers, improving the process each time. I’ve finally settled on a system that enables me to figure all the dormer measurements precisely, cut and assemble most of the pieces on the ground (or in the attic), and put off cutting a hole in the roof until the last minute—no blue tarp needed.
This system is safer…