Contractors are accustomed to offering estimates or providing roof repairs that don't result in a real work contract: the homeowner simply "researches" or chooses a lower price.
For roofing or roof repairs, this can include calculating hours, arrivals and transitions to potential workplaces, and raising and lowering ceilings you may never have worked on.
You can easily quote roof repairs right off the ground and even by phone or email if the home owner can provide some measurements and drawings.
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Some complex roofs may require ascent and accurate measurement of cells, sidewalls, chimneys, and ceilings, or inspection for rot or damage. However, most roof assessments can be done from the ground up by following these simple steps.
Measure the house and calculate the slope of the roof
Draw a simple diagram of the ceiling and note and mark any changes to the slope, limahoi, tripods and boundaries, chimneys, ventilation pipes and other translucent elements.
Then all sections of the exterior wall are measured corner to corner, by adding projections or ceiling mounts. Record these measurements in the appropriate places on the table.
Then calculate the roof slope, which is usually measured in inches. Few customers know the height of their roof and can give it to them, but it's easy to determine this yourself.