above angles appearance building capping cover covered covering edge exhaust-pipes exterior external grooved grooves height high roof roof-area roof-capping roof-whirlybird roofing rooftop shapes sky sunlight sunshine textures tiles tiling turbine-ventilator vent ventilation ventilation-exhaust-pipes ventilation-system ventilator vents whirlybird whirlybirds wind-turbine metal open-sided paved paving pedestrians people posts ribbing rounded shelter steel support walking walkway colorful reed roof cover warm warm color cleaning danger dangers ear protection high-pressure improvement maintenance pressure pressure-cleaning renovating renovation repairs restoration restoring risks risky safety skies spray tools tough water wet work workman architectural color colored colors colour coloured colours dark edges edging elements light lines perspectives protection protective rows shade shadows surface surfaces wavy beneath glass glazed rain station