Steep Roof Replacement on a Story-and-a-Half — Dormers and Staging
You have a steep-roofed story-and-a-half or Cape Cod with dormers and bedrooms under the roof, and the quotes are higher than your neighbor's rambler for the same footprint; here is why and what the job involves.
Steep roof replacement on a story-and-a-half house is slower per square than a rambler: the main slopes are too steep to stand on, so JMB Builders works from roof jacks and planks with harnesses anchored at the ridge, and every dormer adds walls to step-flash, a valley and a small roof of its own. We also fix the ventilation in the side attics behind the knee walls while the roof is open. Across the Twin Cities metro, priced per project.
- Roof jacks, planks and harness anchors on steep slopes
- Each dormer: step flashing, kick-out, valley, cap
- Knee-wall side attics vented while the roof is open
- Send photos, reply within one business day
- Licensed MN contractor BC809005
Send photos and hear back within one business day — or book a free in-home estimate.
The story-and-a-half is everywhere in the older Twin Cities suburbs: a steep main roof, bedrooms tucked under it behind knee walls, and one or two dormers poked through for headroom and light. The same footprint as a rambler carries far more roof surface because of the pitch, and almost none of it can be walked without staging. Those two things, surface and staging, are why the number is higher.
On a slope that steep we set roof jacks and planks in rows as we go up, anchor harnesses at the ridge, and carry bundles up in smaller loads. Tear-off is slower because debris slides and has to be controlled rather than raked off the edge. Every dormer is its own small roof: two sidewalls that need step flashing, a front wall or window head that needs flashing, a cricket or valley where it meets the main slope, and a kick-out at the bottom corner so water does not run behind the siding. A house with two dormers has roughly a dozen extra flashing details that a plain gable does not.
The part homeowners cannot see is the side attic behind the knee walls. On most of these houses the only path for air is from the soffit, up behind the knee wall, through the narrow sloped ceiling bays and into the small upper attic. Those bays are usually packed with insulation that blocks them, which is why the upstairs is hot in July and the eaves grow ice dams in January. With the roof open we can add baffles from above where the bays are blocked and make sure the ridge vent has intake to pull from. That is the one chance to do it without opening the sloped ceilings inside.
What you supply
- Photos of each side of the house from the yard, showing the dormers and the roof edges, and any from the side attics
- Your shingle choice from samples at the free in-home estimate
- Driveway and yard space for the dumpster and staging; cars out from under the eaves on tear-off day
- A heads-up about upstairs rooms with sloped ceilings, where dust falls from the nail holes
What JMB supplies
- Roof jacks, planks, ridge anchors and harnesses, set and moved as the courses go up
- Tear-off to the deck with debris controlled on the slope, decking replaced where soft and quoted per sheet
- Ice and water shield at eaves, every valley and dormer cricket; synthetic underlayment elsewhere
- New step flashing on every dormer sidewall, head flashing, kick-outs at every dormer corner, new boots and caps
- Ridge vent with the slot cut, baffles added from above where the sloped bays behind the knee walls are blocked
- Architectural shingles, matching hip-and-ridge, the city's permit and inspection, magnet sweep, finished photos
How it is priced: per project
Quoted in writing from your photos, with a reply within one business day. What moves the number:
- Pitch: everything on a steep slope takes longer per square and needs staging set and moved
- Squares: a story-and-a-half carries far more roof surface than its footprint suggests
- Number of dormers, each adding walls, a valley or cricket, a kick-out and its own small roof
- Decking condition, often plank on these houses, overlaid where the shingle maker requires
- Ventilation work: baffles into blocked sloped bays, soffit intake opened, ridge vent sized to it
- Height of the eaves and access for the dumpster and material lift
- Chimney flashing rebuild and skylights, common on these roofs, as separate lines
Send a photo of each side of the house from far enough back to see the whole roof, and one from inside a knee-wall access if there is one.
How long it takes
Two to three days on site for most story-and-a-half houses, driven by the pitch and the dormer count rather than the footprint. Plank decks or a chimney rebuild add time.
How your project works
- 1
Send photos, get a written quote
Send three photos of the space and a sentence about what you want. You get a clear, itemized reply within one business day. Prefer a look in person? A free in-home estimate is always an option.
- 2
Pick materials, or bring your own
We help you choose profiles and materials that fit the house and the budget, or match your existing millwork exactly — or you buy the door or trim yourself and we install it. Everything is confirmed before the crew is scheduled.
- 3
Clean, precise installation
The crew shows up on time, protects floors and furniture, and installs with tight joints and consistent reveals. Photos of the finished work go in your job folder.
- 4
Walkthrough and invoice
We walk the finished work with you. If anything is not right, we fix it before we call the job done. Then one invoice, paid by check or direct deposit — no card fees, no payment links.
Situations and options
Gable dormers
The small peaked dormers common on Cape Cods. Each has two valleys where its roof meets the main slope, two step-flashed sidewalls and a kick-out at each bottom corner.
Shed dormer
One long, low-pitched dormer roof across the back. The low pitch gets full ice and water shield under the shingles, and the long sidewalls need continuous step flashing with a kick-out at the eave end.
Knee-wall ventilation during the reroof
From above, we open the blocked sloped bays and set baffles so soffit air reaches the upper attic and the ridge vent. The one chance to do it without opening the upstairs ceilings.
Story-and-a-half with a cathedral section
Some have a vaulted room with no attic at all. That section can get rigid foam over the deck during the reroof, which is covered on the cathedral ceiling page.
Steep Roof Replacement on a Story-and-a-Half — Dormers and Staging: questions, answered
Why does a steep roof cost more to replace than a low one?
Two reasons. There is more roof: pitch adds surface, so a story-and-a-half carries far more squares than a rambler with the same footprint. And every square takes longer: the slope cannot be walked, so roof jacks, planks and harness anchors are set and moved as the work goes up, bundles go up in smaller loads and tear-off debris has to be controlled instead of raked off. The materials per square are the same; the labor per square is not.
How are dormers handled during a roof replacement?
Each dormer is reroofed as its own small roof and tied into the main slope. The sidewalls get new step flashing woven in with the shingles, the bottom corners get kick-out flashing so water does not run behind the siding, the roof-to-roof joints get ice and water shield under a valley or cricket, and the dormer's own ridge is capped. A house with two gable dormers has roughly a dozen flashing details a plain gable does not.
Can you fix the hot upstairs and ice dams on a story-and-a-half while reroofing?
Partly, and this is the time to do it. The sloped ceiling bays behind the knee walls are usually packed with insulation that blocks the air path from the soffit to the upper attic. With the deck open we add baffles from above where they are blocked, make sure the soffit intake is open and cut a proper ridge vent. Air sealing the knee walls and the attic floor from inside is separate work on the insulation pages, and it is the other half.
Do you need scaffolding for a steep roof replacement?
Not usually. We stage the roof itself with roof jacks and planks in rows and anchor harnesses at the ridge, and that is how the whole slope gets worked. Scaffolding or a lift comes into it when the eaves are very high over a walk-out or when a chimney needs rebuilding. If it is needed it is a line on the scope.
Will the dust come through my upstairs ceilings?
Some will. On a story-and-a-half the sloped ceilings are nailed to the same rafters we are hammering on, and there is often no attic space between to catch what falls. Expect fine dust at the nail holes and along the ceiling seams upstairs, and a bit more if the deck is plank. Cover beds and dressers in the upstairs rooms on tear-off day and we will tell you which rooms are under the work.
Why do story-and-a-half houses often have plank decking?
Because most were built before plywood was common; the roof deck is boards nailed across the rafters. If the boards are tight and sound they can be shingled over. If there are wide gaps or split boards, the shingle maker requires an overlay of plywood or OSB so the nails hold. We check from the side attics at the estimate and confirm after tear-off, with the overlay quoted per sheet.
Recent JMB work, from our job log
59 installs recorded across 30 Twin Cities communities since Dec 2025. Window and door installs for homeowners, builders and dealers. Counts come straight from our job log; no customer names.
Get a written quote for this job
Three photos and a sentence is enough: a reply within one business day, or ask for a free in-home estimate. Or text the photos to 763-333-4066.
Related jobs we do
Roof Replacement Contractor — Full Roof Replacement, Start to Finish
Your roof is at the end of its life and you want one contractor for the whole job: inspection, materials, tear-off, deck, flashing, permit and cleanup, with the number written down before the first shingle comes off.
Read moreKnee Wall Insulation — Story-and-a-Half and Cape Cod Side Attics
The upstairs bedrooms in a story-and-a-half are hot in July and cold in January because the short walls and the slopes were never insulated right; we fix the wall, the floor under it and the slope together.
Read moreCathedral Ceiling Ice Dams Fix — Vaulted Ceiling With No Attic
Ice dams build every winter along the eave over the vaulted room, even though the rest of the roof is clear. There is no attic to crawl into, so the fix comes from inside or from the top.
Read moreRambler Roof Replacement — Low-Slope Single-Story Roofs Done Right
You own a 1950s to 1970s rambler with a low, wide roof, the shingles are going, and you want it done in a day by someone who knows what a shallow pitch and a deep overhang do in a Minnesota winter.
Read moreChimney Flashing Repair — Step and Counter Flashing Rebuilt
A stain on the ceiling next to the fireplace, wet brick in the attic, a ring of roof cement around the chimney — the flashing rebuilt in metal, cut into the brick, so it stays fixed.
Read moreRoof Replacement Day — What to Expect and How to Prepare the House
The roof is scheduled, the dumpster is coming, and you want to know what the day looks like from inside the house: where to park, what to move, how loud it gets and what is left behind when the truck pulls out.
Read morePage reviewed October 2, 2026 · JMB Builders LLC, MN license BC809005 · All roofing pages
Where we work
Roofing near you
Based in Zimmerman, scheduling across the Twin Cities metro. Closest first: