Ask Katie: Thoughts on adding a garage to a ranch

Q: I’m currently remodeling my 1960s single-story ranch home. My question is whether you think it’s possible to add an attached garage (with living space above) without dwarfing the original box-type ranch? I believe that I’m constrained by the original 6/12 pitch of my ranch and the height needed for living space above the garage.

 Matthew from Westfield, MA

A: This is tricky. You’re right; you’ll want to modulate the difference between the eave/roof height of the existing ranch and that of the new garage which has living space above. Otherwise, the new, taller addition could easily overwhelm the existing, single-story building.

For the sake of this discussion, I’m going to make the following assumptions:

  • You’d like to leave the original ranch largely intact as a single-story structure.
  • The existing ranch is sited with its long dimension facing the street (meaning that it’s side-gabled).
  • You have town-approved room on your property adjacent to the ranch and farther back from the street for a small connecting space and the new garage.
  • Your local zoning and other governing authorities will allow the use of the living space above the garage and the height required to accommodate it.
  • The new garage houses one car, some storage space equal to about half of a car-stall, and an interior stair. (A smaller garage will make the contrast in size between the house and garage -- which has living space above -- less of an issue.)

Creating a space that links the existing ranch and the new garage can help the transition between the two. I’d recommend a small single-story open breezeway or arbor to act as the connecting link. If you prefer that if be enclosed, treat it as an enclosed porch with a lot of natural light and transparency. Use a flat roof or a medium-low pitch gable like the ranch roof. If possible, step it back from the front of the ranch and such that it intersects the garage a few feet from the front of the garage, which should also step back from the front of the ranch. This will help to keep the ranch prominent when seen from the street.

Consider using an asymmetrical side-gable roof on the new addition. The roof slope on the addition will need to be steeper than the ranch roof slope. Try a 9/12 or 8/12 pitch. Start the eave on the front just high enough to accommodate an overhead door and its tracks. This will make the front eave fairly low, though perhaps slightly higher than the original ranch eave line. Then slope the roof away from the street to a ridge point that is beyond the center point of the garage footprint; this makes it asymmetrical. The ridge should be just high enough to accommodate a small second-story living space under the rafters. Match the slope used on the front of the new addition on the back too. Receive the rafters on the rear with a knee wall, five feet or less above the finished floor, and include a rear shed dormer with an eight-foot plate height to improve interior function. Try a medium-low 6/12 roof slope on the dormer, like the ranch roof pitch, or something as shallow as a 4/12 slope if that works better.

This is a one and one-half story solution. When viewed from the side, the addition will appear somewhat like a saltbox, with a low eave line on the front and higher eave line on the back. You may want to place a shed dormer on the front, set back from the face of the garage below, and nested in the overall roof in order to increase daylight and headroom. Match the slope of the rear dormer on the front dormer.

Place the stair to the new upper level within the garage footprint. A straight stair traveling up in the same direction as the front roof may make sense. Stairs are always a challenge, so you’ll need to try several placements to find the best and most functional solution. You may be required by your building official to include a second egress stair, so be sure to check.

Run an arbor behind the new addition (if the orientation and use makes sense) or attach some lean-to type storage compartments for yard or summer equipment to keep the rear elevation of the addition from appearing overly tall. The lower eave height of the arbor or lean-to will help soften the height of the addition.

For folks wondering about other attached and detached garage solutions, click here to see a PDF of a garage story that I wrote and illustrated for the Fine Homebuilding June/July 2007 issue, or click here to go to the Journal of Light Construction website to access a garage story that I wrote and illustrated for them.

by Katie Hutchison for the House Enthusiast

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