Water proofing of buried foundations- can it be avoided in dry ground condition?

[sfat]

Hi,

I am facing this issue raised from Client and Architects, that if the condition of ground is dry, and ground water table is very deep in the site area, they ask not to water proof the RCC sub-structure (isolated/combined foundations and plinth beams). Please note that there is no basement, and structure is residential-one unit. They ask me to suggest admixture for water proofing in concrete but want to avoid external water proofing to save time(i don't put my trust fully on admixtures). My concern is , that water can penetrate in soil from nearby leakages of plumbing lines, and rain water (though it seldom rains here, once a year) etc.

I have also noticed in many projects of structural assessment of existing structures, that when i get foundation dug for 25 or 30 years old RCC structures to inspect, foundations are always found in good condition, i.e. concrete cover intact and in good condition. I don't observe any waterproofing layer in such cases and see bare concrete surface. It might be the case that waterproofing layer had disappeared/eroded over time? but my point is, that can the water proofing of substructure in dry condition area be avoided?

 

[hokie66]

Yes, in the conditions you described, waterproofing is not necessary. Reserve your waterproofing efforts for things above the ground.

 

[MTNClimber]

Sounds like waterproofing can be omitted. I've seen waterproofing still used in areas that are dry but there is high risk of sulfate attack from the surrounding soil. I'm not sure if you're in an area where this is a problem.

 

[Ron]

Omit the waterproofing. Not necessary for your application. You don't need an admixture waterproofing either. As long as your cover on rebar is ok.

 

[sfat]

Thanks all of you!