Project Description

The development is a renovation considering green building concepts. The old building was a residence and recently renovated into both house and an office. The existing ground floor was developed into residential unit and the first floor was developed into office function. The concept of this building is to build an Architectural office for the designer with the residential capacity. Therefore, before selecting the site there were many considerations being an architectural practice it was not required to locate the office in a city centre. However as the practice is engaged with government institutions it was decided to find a location within the administrative capital. The land was 18.6 perches or 470m2 in extent surrounded by a 12m road and located in a residential zone. Where professional offices are permitted. The property was specifically selected as it was within 60m from the owners’ residence and approximately 60m from the main bus route. However it was purchased with knowledge of the complication related to the existing building on it.

Rna 2
Rna office
Rna office copy
Rna m

Building Details

Office + Residence - as a convertible space

Renovated building project

470 m²


312 m²

288 m²

172 m²

Gold Rated, Green Building Council of Sri Lanka

EURO 68,500

EURO 220



Project Team

Ranjan Nadesapillai Associates


Mr. Gamini Wijeratne

Eng. Nilan Herath

Archt. Ranjan Nadesapillai

Archt. Ranjan Nadesapillai, Principal Architect of RNA counts over 30 years of experience since graduation. He is a Chartered Architect and Fellow Member of the Sri Lanka Institute of Architects. Fellow Member of the Royal Institute of British Architects,, Chartered Member of the Institute of Environmental Professionals of Sri Lanka, Fellow Member of the Institute of Management of Sri Lanka ,and an Accredited Professional of the Green Building Council of Sri Lanka. Currently he is the Immediate Past President of the Sri Lanka Institute of Architects. His experience also include five years in the Urban Development Authority of Sri Lanka in the early 1980's. While in the Private sector he had the privilege of being associated with some of the prestigious projects in the early 80’s In the state sector his scope of work included Architecture, Planning , Urban Design and Project Management and serving on many statutory committees including Cabinet Appointed Tender boards. In 1989 he resigned from the UDA and established the practice RANJAN. NADESAPILLAI ASSOCIATES primarily an Architectural Practice serving several projects in collaboration with allied professionals as consortium consultants. In the Practice he plays the role of Principal Architect and Project Manager.

Eng. Palitha Abeywardene

CQS. Upali Jayalath Quantity Surveyor

Climate Analysis

Pelawatte has a tropical climate and fair temperature all throughout the year. The temperature averages around 31 degrees Celsius maximum from March to April. The April is the hottest period of the year and shading is seen as the best effective method of cooling. You can find major changes in the weather during the monsoon seasons from May to August and October to January when heavy rains can be expected. The solar radiation during the day sometimes border on intolerable because of the combination of heat and humidity.

Solis ortus

Design Approach

The selected site is a plot of land from a subdivision of a Rubber estate. Most plots are around 20 perches in extent and maintain open landscape spaces around them; maintaining approximately a plot coverage of 60% or less. Thus was decided that the development should no be more than 50% plot coverage. The development was restricted to 31.23% plot coverage.

A typical sub-urban neighbourhood in the nations capitol. Re-use of the existing buildings was the main focus to reduce carbon consumption and avoid greenfield site development. The project brief encompassed the need for hardscape in the open areas of the building. The following methods were used for more than 75% of the hard-scape, in the courtyard and parking lots to reduce negative impacts. Provide shade utilising the existing tree canopy. Vegetated areas as courtyards Paving blocks that have the least solar reflection with grass in between The existing building was oriented to the South East –North West axis. Therefore cutting down direct light and radiation was a major concern. Out of the types of roofs which are commonly used, gable roof with long eaves was a better option. The steep angle helped to cool the interior by taking the hot air up. Also the roof facing the North West was an ideal location to fix the solar panels for building’s operation.
New picture %286%29


Special Feature

Solar energy generated contribute to reducing the use of power from the national grid .Solar powered & powered sensor operated lights to illuminate the exterior to minimize light pollution. The glass used on windows in upper floor minimize the glare and heat contributing to making the internal environment cooler and comfortable. Perforated blinds control glare and radiation, yet allow visibility.

WATER EFFICIENT LANDSCAPING From the calculation, it is observed that rain water is more than enough for the irrigation. Planted and turf, trees does not need daily supply of irrigation. Therefore quantity of portable water used is negligible Added water efficient fixtures to reduce water demand – mainly dual flush WC etc. In the near future for landscaping a permanent arrangement with well water will be installed for irrigation. WATER EFFICIENT IN A/C SYSTEM Use of AA type of A/C machine which does not require water for cooling is used in the building Generated water from the A/C machine is directed to the landscape areas

Building was designed to obtain optimum ventilation and have optimum temperature. The average air temperature in the interior is maintained at 26 deg.C for thermal comfort and economy.

Stabilised soil blocks as a primary element for new walls are deemed cost effective in terms of building and Life-cycle-cost.

Light fittings with low energy bulbs are provided for each work station with individual switches

Re-use of existing buildings and materials is an important factor considered in the approach.

Building Material

Renovation of an existing building was a key decision. After studying the existing building it was needed to demolish most internal partition walls, to achieve a open plan concept which is ideal for a office set-up. Only the store area, care takers area, toilets and the meeting room was enclosed. Structural engineer’s recommendation was to preserve the external walls of the building, and strengthen with a new grid including columns. The weight of the proposed upper floor is transferred through the new grid as a independent structure.

RCC individual pads for new structural grid

Ground floor walls were made of used and recycle bricks. Walls on the upper floor were constructed using ECO BRICKS. Which is an Eco friendly building block constructed with 70% clay.

Doors and windows use aluminium framed glazed units, with single-glazing. User controlled internal shade screens, shade and reduce glare.

Cement float, cut and polished. Provided a cost effective, low maintenance finish. High Floor reluctance is also an advantage.

LOW EMITTING MATERIALS Painting and Coatings Use of paints and coatings which do not exceed the VOC limits. Clear floor coatings, stains, sealers and shellacs do not exceed VOC limits established in SCAQMD Rule #1113, Architectural coatings.

The roof is made of insulated Zinc Aluminium sheets, that includes a timber ceiling. The roof is covered with series of solar panels. Solar panels also serve as a protective layer reduces the direct heat gain from sun.

Composite timber and Agri- Fibre products ECO Groove 150 Is an engineered wood product manufactured from wood chips, sawmill shavings, or even sawdust, and a synthetic resin or other suitable binder, which is pressed and extruded. Particleboard is a composite material which can be used as a substitute for timber cladding etc. This material was used for the boundary wall replacing the solid high wall that existed.

Energy systems

linear florescent and compact florescent lamps. Individual control at task spaces. Ambient light is primarily from daylight integration

Solar powered LED Motion Sensor controlled to avoid excessive light pollution in the night time.

Ceiling and wall mounted fans in selected areas in office floor.

Split AC units. Maintain an average temperature of 26 deg.C in the office section of the development. The residential / multi-use space on the lower level is naturally ventilated.


Motion Sensor controlled to avoid excessive light pollution in the night time.

Installed the solar power renewable energy system to acquire almost 100% of the energy. And also installed the system to provide the excess energy to national grid.
New picture

Lessons Learned

The biggest challenge of this project is to renovate the existing residential building to a mix development of residential and office. The analysis was required in both ways to understand the quality of the site as well as the quality of the existing building.

The building user enjoys the developed project such as Low energy use, Lower operating costs, Fewer contractor callbacks, Better building documentation, Improved occupant productivity, Verification that the systems perform in accordance with the owner's project requirements. Since the renovation used green materials such as eco bricks etc, a lesser amount of maintenance required. However, the landscape maintenance were done by the user while developing landscape into a vegetable garden. Therefore, the additional maintenance cost was recovered.

''Today all the staff and the family enjoying the quality of the developed site. Not only human users but also animals such as , birds, squirrels, bees and monkeys reap the benefits of this development '' - RNA