The home's size and roof lines should look harmonious with the upper deck level. Sketch the house and surrounding yard to figure out the height of the uppermost deck level. You might sketch a deck to extend from the upper level of a bi-level house just outside a bedroom, for example. Make this level harmonize with the house roof lines and the overall structure. You will need to ensure this upper deck level looks appropriate from every yard angle.
Design a lower level to flow with overall yard space and landscaping. This level might look appropriate just one or two feet lower, for example. You will need to make various sketches of the whole house, both deck levels and yard areas to surround deck space. Decking should blend with the house in terms of placement and size. The deck space should not stand out more than the house.
Measure the house and yard space in detail. Draw these areas, plus the planned deck space, on graph paper. Figure out railings, steps and deck furniture that will look harmonious with the house. As one choice, plan to slant railings outward around the entire deck. You may want to add mulch areas and landscaping details along the railings of the deck. The two deck levels should not look overcrowded with outdoor furniture or too many landscaping details.
Railings and bench seating in the overall design will tie both levels together. Think in terms of unifying upper and lower levels using color or materials as well. You can use metal railings with lumber floor decking for a different look. Add bench seating that functions as storage cabinets as a possible choice. Storage boxes with hinged lids can serve as deck seating, so you can store outdoor lawn cushions or other items inside.
If you desire, add steps between the two deck levels and a roof cover. Plan steps with a handrail to connect the upper and lower levels in a visually pleasing way. A staircase with a handrail might be appropriate if the height difference between the decks is significant. Design a small patio cover over part of the upper or lower deck to create shade. The roof cover might be a standalone patio cover, or you can secure it to the house roofing.