Solar in Manchester starts with the roof the mill or the house actually has. A flat Amoskeag roof with parapets, drains, and mechanical curbs is not a pitched roof on a North End cape. Tall brick neighbors shade the millyard for much of the day. Trees shade the houses. A membrane that ponds or a shingle roof with two tired layers should be fixed before anything is fastened to it. Say the building before you talk about the sky.
New holes in a worn mill membrane become the next leak into a top-floor unit. On a house, ice and a valley full of seeds will find a bad flashing faster once the roof is disturbed. Snow slides off a smooth pitched surface onto entries and lower roofs. Hardware has to live with wind in the valley. None of this is a forecast of output. A phone call that pretends to know production is not a serious call.
Electrical gear in a mill unit may be a small panel far from a roof hatch, or part of a house service that is already full. Damp basements and crowded mechanical rooms change the path. Walking a flat roof among drains and curbs is a layout problem, not a blank rectangle. Slate is uncommon here compared with the villages, but a decorative or steep house roof still should not be drilled casually. Mention access: stairs, hatch, or a narrow side yard.
Shade you cannot remove, including the brick block next door, belongs in the first conversation. So does a roof at the end of its life. Ask how mounts or ballast will respect the drains and how a later leak gets closed. A unit under the roof deck needs to know where people can still walk. Say if the roof is shared, because one owner cannot give away the parapet.
Call with mill or house, flat or pitched, and what shades the surface. Mention drains, trees, or a soft deck. Ask about structure and flashing. Do not expect a production promise. Call the number on this page.