A carriage house over a Ladue garage puts two roof lines and a living space under one address. The garage roof runs lower, the apartment roof rises above it, and the place where they meet is where water tends to find its way in. Before anyone orders shingles, the roof plan has to say how the crew reaches the upper slope, what happens inside the apartment while the tear-off is underway, and how the wall between the two roofs is flashed. Those three questions decide more of the price and the schedule than the square count does.
Town roofing
Many older Ladue houses have a garage or outbuilding set back from the main house, and some have a room or two above the garage used as a guest suite, a home office or a storage floor. From the street the building reads as one structure. From the roof it reads as two. The garage roof usually has a lower pitch and sits against the wall of the upper room. The upper roof has its own ridge, its own valleys, and often a dormer or a gable end facing the drive.
In St. Louis the freeze and thaw cycle works hardest where two roofs meet. Snow that melts off the upper slope runs down and stops at the lower roof edge. If the lower roof is cold and the eave is not ventilated well, the water refreezes and builds an ice dam. Meltwater then backs up under the shingles and can run along the wall into the apartment. A carriage house is one of the common places this happens, because the apartment wall is heated from the living space while the garage roof above an unheated garage stays cold. The roof plan should say how that junction is flashed and how the eave is ventilated, not only which shingle goes on the field.
Access is the second question. A crew can reach an upper slope by a ladder from grade, by a ladder set on the garage roof, or by a stair through the apartment itself. Each choice changes where the ladders land on the lawn, which beds or walks get crossed, and whether anyone has to move furniture in the apartment to reach the attic hatch. On a Ladue lot with mature trees and landscaping close to the garage, the ladder landing can take as much room as the dumpster. Ask the roofer to mark the planned ladder spots on a sketch of your lot before the date is set.
Winter adds its own problem. If the drive is steep or the garage apron is shaded, the crew may need to clear snow and ice before the first ladder goes up, and a frozen apron can turn a short delivery into a long wait. Ask who clears the access path on a cold morning and whether the bundles will be staged where they will not be blocked by melt.
Hail season matters too. In the spring and early summer, the upper slope of a carriage house usually takes wind-driven hail first, so the walk of the upper roof should be photographed slope by slope before the tear-off begins. Document the dents on the apartment siding and on any gutter section along the upper run, since they show which direction the storm came from. Keep the photos as originals with their date data, not as screenshots, so the file can be checked later.
What it costs
A carriage house roof is priced as a roof, but it carries extra lines that a plain gable roof does not. Ask each roofer to show these as separate lines so you can compare them directly.
- Wall flashing where the upper roof meets the apartment wall, whether that is step flashing woven into the siding, counterflashing set into a reglet, or a kick-out at the lower roof edge. This is usually counted by linear foot, and it is often missing from a quote that lists only the field shingles.
- Valley work at the junction of the two roofs, including the metal, the underlayment and any ice and water membrane the roofer adds at the eave.
- Access setup, meaning ladders, a stair section or a scaffold, and the time needed to move them each day.
- Protection inside the apartment: floor coverings, removal or covering of wall hangings above the work area, and the dust control needed when the attic above the apartment is opened.
- Any exterior stair, railing or light fixture that must come off and go back on.
- Permit fees, if the work needs a permit, and any inspection the municipality requires for a roof over a living space.
A quote that puts all of this into one line for the whole house is not showing you the job. Ask for the lines to be split so that the upper roof, the lower roof and the apartment work can be compared on their own. If one bid includes the apartment protection and another leaves it out, the lower total may only mean the second roofer expects to work around the apartment later, and that expectation should be written into the proposal.
Permits are handled by the municipal building desk for the city or county where the house sits. Ask the desk whether a roof over a finished living space triggers a permit or an inspection, and ask the roofer who will pull it and whether the inspection has to happen before the roof is covered. Get the answer from the desk, not only from the roofer, and keep a note of who you spoke with and when.
Keys Roofing installs Atlas and Malarkey shingles. Whichever roofer you talk to, ask that the shingle line, the underlayment and the flashing metal be named in the proposal, so a later substitution shows up on paper. Keys documents damage and puts a written scope with photos and measurements in the homeowner's hands, which is the document to set beside every other bid.
What to ask
Bring these questions to each roofer and write the answers down next to the proposal.
- Show me on a sketch where the crew will set ladders, and which walk or bed each ladder crosses.
- Will the crew enter the apartment for any part of the work, and if so, which rooms and which ceilings sit below the upper roof?
- How is the wall junction flashed: step flashing, counterflashing in a reglet, or a kick-out at the lower edge?
- How is the eave ventilated above the garage roof, and what membrane runs up from the lower edge?
- Which lines in your proposal cover the apartment protection and the access setup?
- Who pulls any permit, and does the municipal building desk require an inspection before the roof is covered?
- Will you photograph the wall flashing before the cover goes on, and will I receive those photos?
- Who clears the access path and the drive on a cold morning, and where will the bundles wait if the delivery arrives early?