Part of the Kenyan Architect ’s responsibility in green architectural design is to ensure that water sustainability is achieved in the project. Water being one of the key natural resources that are necessary for human activity and habitation must be maintained and conserved. Every source of this precious commodity  must be rationalized, and proper care taken for it to be maximized to all reasonable extents. Rainfall is one of the most abundantly available natural source of water, and maximizing water from this source is of concern to any building consultant or developer interested in doing sustainable projects.

Achieving Water Sustainability Through Rainfall Management, Tips for the Kenyan Architect

water landscape for Kenyan architect

water landscaping

Rain falls during various seasons of the year, and in some cases may even come suddenly in the course of time. Rainfall patterns along the equator can be forecasted and peak periods are well known for purposes of planning. However due to global warming, climatic conditions have started varying and rainfall patterns may not be as predictable as previously. In addition, pollution in urban areas has added to climatic woes such that rainfall in certain areas with heavy industrialization ends up becoming polluted and acidic. In such areas, it is not advisable to depend on rainfall water as a source of water for heavy domestic use; rather it can be used for non-potable uses.

However in areas which enjoy clean atmospheric conditions, one may find that water being harvested in these areas being suitable for domestic usage. In this case residents require to proactively harvest this water when it is available for future utility. It is not wise to let this wonderful natural resource to flow away without making proper use for it.

Harvesting rain water requires proper provisions to be integrated within the built structure by the Kenyan architect right from the planning and design of the development. These elements for water harvesting do have spatial considerations that need to be taken in order for the design to integrate them intrinsically, rather than adding them as superficial elements later once the project has already been occupied and in use.

Rainwater Harvesting; Design Provisions That The Kenyan Architect Must Consider

Roof Collection of Rain Water, Importance of Compatible Roof Coverings to the Kenyan Architect

This is one of the most basic elements of a building that can be used to harvest rain water for domestic use. In order to do this, the roof needs to be constructed out of materials that are non-toxic to human beings, and loose impurities that can be carried by rain water need to be avoided. Materials such as asbestos and other carcinogenic substances in the makeup of the roof covering cannot be tolerated and should be avoided altogether.

Traditional roof coverings which support rain water harvesting include roofing constructed from clay tiles, as well as concrete tiles. It is preferable that these are constructed on roofs with a moderate to steep pitch of at least 15 degrees to avoid stagnation of water and accumulation of algae on the roof surface.

Use of stone slates or wood shingles have been another traditional roof cover offering attractive homely finishes yet also allowing for harvesting of rain water from the roof. These also require relatively steep pitches to avoid accumulation of undesirable algae on the roof, as well as ensuring that the roof does not have leakages.

In areas where they are available, a simple material that can be used as a roof covering that supports rainwater harvesting very well is galvanized iron sheets. Even better are prepainted galvanized iron sheets as these have a longer lifespan and are more rust averse than normal iron sheets. These can be easily cleaned if the building is situated in a dusty area, or allow for collection of rainwater a few hours after rainfall has begun so that surface impurities are swept of the roof covering first.

New roof coverings have since been invented which support for collection of rain water from the roof surface. Granulated stone coated zinc/aluminium roofing tiles have become a favorite among many developers as these have the same appearance as traditional clay or concrete roofing tiles, yet they are much lighter structurally. This would assist to make some savings in the roof structure required to carry these tiles as the roof covering.

Required Roof Fittings And Furniture That The Kenyan Architect Must Incorporate

A good roof covering requires having good roof furniture in order for it to be functional for harvesting rain water. These typically include elements such as gutters, roof drains and downpipes, which channel water to their points of collection. These can be made of matching materials as the roof finish, and should be selected in a manner as to enhance the building’s aesthetics. Pre-painted gutters can match the color of the roof or contrast attractively.

Roof furniture needs to be in good condition to ensure that it does not have problems with leakages. In addition they should be appropriately sized to cope with the quantity of water that would be expected to be channeled through them. These can be properly calculated by the project’s engineers who are able to estimate the volumes of rainwater that will require to be channeled through the pipework to the final harvesting points.

Rainwater goods require to be checked often to ensure their functionality. Full-bore drainpipes for example require to be regularly cleaned to ensure there are no blockages. Other elbows, drainers and junctions need to be fixed and anchored firmly, and especially should be able to have adequate ability to cope with the rigors of the environment. It is preferable that these are also finished to complement the aesthetics of the built development.


The Kenyan Architect who designs these construction elements and integrates them into the detailing of his building project is able to achieve greater success in water  harvesting and sustainability techniques. These simple provisions will assist a client or developer obtain greater value for their projects through proper sustainability provisions. Green and sustainable developments are thus achievable for the Kenyan Architect through use of these principles.