Basement Drainage in South Africa

Hi All

Im a South African Student currently studying Civil Engineering. I have to write a paper on basement drainage solution for existing homes. The problem is there are not a lot of basements in SA! You guys in the US have a lot more first hand experience and I hope you could help me out. My project needs to include a short(5page max) guidebook in which I describe the different causes of dampness in basements, different solutions/systems and some kind of a flow diagram that a homeowner can follow to arrive at a solution. The diagram will start with a the problem and then site specific questions etc will elliminate some solution until ariving at a solution.

This is what I have so far only problems caused by groundwater is considered+condensation, no burste pipe or water from other floors etc)

The main sources of damp
Lateral penetration(seepage)
Rising damp
Condensation
Rising water table(flooding)


The solutions

External drainage(french/fin drains)+sump
Chemical damp proof course
Internal cavity drainage system+sump
Dampproof Membranes(interior or exterior of wall)
Waterproof membranes(interior or exterior of wall)

Can you guys tell me which systems are the best and cheapest for each type of problem. Any help will be greatly appreciated!

Are there any similar guides available???

Thanks a lot

Ernst

 

I would have to write the paper myself to answer those questions. I will say one thing though. Remove interior waterproof membrane as a possible solution. That might work for dampness but not for waterproofing.

 

Don't forget preventative is the best approach. Keep water away, and avoid it as much as possible. Roof drainage and water runoff, as well as an appropriate grade plan must be addressed. this can also include avoiding even the placement of landscape gardens adjacent to foundation walls.

Also consider the type of material used for the basement/foundation walls. Cement block/cinder block verses concrete or even wood. On site poured concrete verses pre-formed walls could also be a possible variable depending upon installation and soil condition. Also consider the site, and the existing normal water table level and relationship in depth to the clay layers. With a shallow water table keep everything high and consider a raised foundation also for example. Everything you mentioned are solutions to address existing water coming in verses possible better planning and building ways to avoid that impact as much as possible and therefore reducing the need or at least impact for all of the tech product based solutions.

 

Try looking at buildingscience.com. I believe they have information there about this topic that could be helpful in your research.