With a room arrangement typical of many antebellum plantation homes, Mableton’s original 1879 floor plan reveals more of its Southern heritage. To maximize natural air circulation through the house, a wide central hall bisects the house from front to back, and opens to shaded verandahs at either end. Typical of the most common plans, two rooms on either side of the central hall each provide additional direct access to the verandah. In lieu of conventional windows, the rooms open to the verandah through “slip-head” windows. Very tall double hung windows that extend to the floor, slip-head windows may also function as doors. Unusually high ceilings were essential to accommodate these oversized window openings within the walls. A highly effective passive cooling system was achieved by the combination of verandah-shaded exterior walls, high ceilings, and interconnected rooms. In Southern examples, sources of heat and potential fire hazards were often removed from the main house, with utility and service areas (such as the kitchen) located in nearby separate structures. Alternately, the kitchen and other service areas were placed in the ground level basement (the location of Mableton’s original kitchen).
In a departure from typical Southern precedent, Mableton’s design allows for the admission of natural light through a long skylight above its central hall. Between the central hall and each of the four flanking rooms, wide doorway openings are fitted with sliding pocket doors. These generous openings perform multiple functions: in addition to sharing natural light between spaces, they enhance cross-ventilation, and allow greater flexibility in how rooms can be used. The unusual width of Mableton’s central hall, and the presence of a fireplace at its far end, permits it to function as both living and circulation space. Designed for entertaining on a grand scale, this plan creates the potential to effectively combine all of the rooms into a single, contiguous space. The surrounding verandah further expands the interior spaces, and reinforces the strong relationship between the house and its landscape
Prior to the development of bedroom space in the attic, all of the McDonald family’s living areas were located on the main (first) floor. It is probable that the two rooms towards the rear of the house were used as bedrooms. However, in the informal context of a summer home, it is likely that these rooms (and possibly the others as well) were employed for multiple uses. Notable is the presence of a large interior bathroom, placed between the two rooms along the south side. This original feature was an unusual luxury at a time when most homes (especially in rural locations) still relied on outdoor plumbing facilities. To better accommodate a growing family, the McDonalds soon expanded the home outward and upward, to include more living, bedroom and bathroom space.