The design considers on the protection of lakeside to minimize the water and air pollution. An unoccupied building could have another benefit by modifying the function of the building into commercial function. The transformation of building function consistent with the local government policy as the effort to increase the quality of lakeside environmental.

However, there are some obstacles during the development of the area. The obstacle factors are erosion or abrasion, sedimentation, and high cost on the siteplan development because the development involve specific technology and construction. Therefore, the formulation of land use concept determines the function of the area as the resort with some supporting facilities to optimize the resort function. The concept will provide an access for the public, providing some green, economical, accommodative facilities for long-term period in order to attract the visitor.

According to the activity that facilitated by Matano Lakeside Resort, there are three resort activities: category, primary, secondary, and tertiary function.

a) Primary function. The function is the primary requirement for the resort, such as:

1) Occupation

2) Entertainment and recreation

1) Administration

The promotion category will facility are the hotel announcement to the tourists and organize the event to attract the visitor to come the resort.

1) Service

A service will support all resort activity, include maintenance /repair and building maintenance.

2) Service function

The function will present a service to the resort guest. All quest needs will provide by service function. The service function facilitated with main kitchen, engineering, praying room, and parking area.

4) Sport

The sport facility is to support the requirement inside the resort. The facilities are swimming pool, jogging track, and outbound area.

The administration related to the all resort management, such as: manager room, staff room (administration), etc.

2) Commercial service

Commercial facility is the facility that support the quality of the resort, such as cafe, ATM, minimarket or convenience store and souvenir shop.

Based on the design theme, the resort certainly presents an entertainment and become a recreative area located in the Matano lakeside. This function is the primary attraction of the resort. The attraction will realize in form of mini waterboom/water park, outbound arena, swimming pool, and some others supporting facilities.

The occupation is the primary function in the design as the place for relaxation, to stay, and enjoying the Matano lake environment from the resort. The resort facility should facilitate the visitor activity to create a comfort atmosphere.

b)Secondary function. The realization of this function is to support or operating the primary function, such as:

3) Promotion

C)Tertiary function. The function is to support the primary and secondary function, which are:

The resort facilities above conclude that the room requirement define by the building function to be facilitated the room inside the building. The next part will describe the site plan of lakeside resort area of the Matano lake and some recreation facilities inside the resort area (see Figure 1).

The site plan is 60,000 m2 or 6 hectares. Total of the lands space is 11,569.31 m2 or 19.28 % of the site plan. 48430.69 m2 is non-built-up area and most area is a reforestation area with big tree and shrub vegetation. The allocation of built-up area and non-built-up area proportion usage is one of the implementations of design with nature concept with the application of balance between resort physical design and reforestation composition in Matano lakeside land.

All wooden material must dry, old, straight, and without a crack, and the humidity degree is less than 15% as the requirement stated in PKKL 1970-NI.5. The selection of wooden material because a wood construction is an accessible material. The material is the material that mastering by the local engineer because the characteristic of wood are easy to cut and flexible (measurable, easy to cut, elastic, and etc.). The truss construction for the roof will resist the wind pressure horizontally and proved by the application in the traditional house. In fact, the construction is standing for a hundred years, depend on the preparation of the wood material (see Figure 2).

The sub structure of building practice the caisson pile to adapt the land contour, and pedestal column applied in the building pile. The middle structure of house building is reinforced concentrate and the upper structure is a wood truss. Some buildings have foot plate sub structure, a common structure found in the high building with soft land condition. The foundation characteristic is economical and the land pit is few that make the project time saving.

The light and the air are the most important elements to provide the illumination into the building interior and sufficient natural ventilation. The elements also present amenities to the user for their activity. The rooms with ventilation and natural illuminance will have sufficient humidity and keep the environment condition. Moreover, sufficient ventilation and natural illuminance will save the electrical energy, because the building will not com- pletely depend on the artificial light and mechanical ventilation. The strategy of natural energy consumption inside the Matano lakeside resort area (see Figure 3).

Energy consumption inside the building will maximize by the implementation of building orientation that positioned between the sun path and the wind (Sahabuddin, 2019). The most advantageous building positioning is to the west from the eastward. The opening head to the South and East to avoid direct sunlight. The building will have enough wind opening, the ventilation positioning is horizontal and vertical, and the larger room positioning will direct to the wind direction. The building considers on the window orientation to the sun with natural material that absorb the heat. The material includes wooden material for the interior, fence and vertical garden, pitched roof formation (simple plane) to reduce the temperature under the roof. The design provides a terrace for the building/house as a transition area between outdoor (yard) and indoor (building) that create a micro atmosphere either inside the building or around the building. The design enhances green vegetation, secondary skin concept on the faced to reduce the heat of the sunlight, providing an open space inside the building, and located the pond around the building area. Moreover, there are implementation of building form configuration, cross ventilation, and skylight to reflect sunlight from the top.

Water efficiency more emphasize on the reuse of rainwater utilization for operational resort. Reservoir system provides a reservation for the rainwater. Reservoir tanks is dark painting to obstruct the growth of algae, enclose, the ventilation is like a filter, and easy to clean (if use for a clean water system). The water Reservoir tank material is from concrete and clay. The reservoir container material is from Fiberglass Reinforced Plastics (FRP) which available in various form and dimension. The reservoir tank or storage is the most important component for rainwater system and usually is the most expensive system. Reservoir water tank located as close as possible to the rainwater splash area and the dimension calculation is based on the requirement, rainfall frequency, wide surface, budget, and aesthetic (see Figure 4). The tank position to the rainfall area and filter in accordance with the water current and important to maximize the water collection. Therefore, some strategic location selected for reservoir tank and along with the characteristic of the location as describe in figure below.

According to the allocation of various room requirement to optimize the resort function, two water tanks should be able provided up to 150,000 liters with consumer standard needs is 10-15 Liters/person/day. The water tank characteristic is communal or center. The water will distribute through the pipe with water pump support.

According to design approach that emphasize the green building concept and design with nature, the material selection priority on the green material. The green material is not only for environmental sustainability, but more efficient and energy saving based on the long-term estimation cost aspect. Green material selection includes the aspect of technology and application. According to the aspect of technology, material selection avoids the toxic contain material and the production is compatible with the nature. Wooden material application is appropriate with the quantity and availability of material in the nature. As long as the site plan area has abundance wood resources then wood utilization still appropriate for the construction process. Moreover, in the utilization aspect, green material selection like is transparent glass material will generate more reflection of the natural sunlight. Wooden is in accordance with the requirement and avoiding produce a residual material.

Most of the material in building resort is used natural material, such as wood, stone, and straw. Moreover, the glass material implemented on the building window. The purlin roof and lath, terrace, and the upper wall is wooden material and the main wall is brick wall.