The financial return on rooftop solar depends on how much electricity you use on site, when you use it and how your supplier credits exports. To assess a system, look beyond the rated output of the modules. The condition of the roof, installation costs and access for maintenance matter too. Review the electricity bills and roof covering together so you can size the system for the building. Generation may peak at midday when the house uses little electricity. The surplus goes to the grid. In the evening, you buy electricity under the terms of your contract. Multiplying the entire annual output by the retail electricity price overstates the savings if you export part of that output at a lower value.

How much noise you hear under a metal roof depends on the entire roof assembly and how well it was installed. A damping layer on the underside of the sheet can help. Its test result describes the conditions of that test, and the effect in a particular room can differ. Start by identifying the source of the sound. Raindrops set thin metal sheets vibrating, and the supporting structure can carry some of that vibration indoors. Wind can also move a poorly secured component. A knock that always comes from one spot gives you a specific place to investigate before considering work on the whole roof.

Metal roofing can suit both a traditional house and a simple contemporary building. The pattern of the profile, the proportions of each roof slope and the treatment of the edges all shape the result. Modular steel roof tiles, tile-profile sheets cut to length and standing seam panels each produce a different effect. Metal tiles divide a roof into horizontal courses that can line up visually with windows and façade elements. Compare the height and number of tile modules on the actual roof drawing. A deep profile can dominate a small house, while a shallower pattern lets the walls and windows stand out. Match these choices to the technical requirements of the roof.

Slight ripples in the flat part of a metal roof panel may only show up in strong sunlight. Residual stress in the metal, the supporting surface, the fixings and thermal movement all play a part. A slight wave does not necessarily mean the roof leaks, but not every irregularity is harmless. Discuss the expected appearance before ordering: panel choice and careful installation do more than attempts to flatten an installed sheet. Small deviations from a flat surface catch reflected light at certain angles. The same roof can look different in morning sun and under cloud. This visual effect is often called oil canning.