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RCC Basement vs Pillar Foundation for Home


BilalAhmad
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I need your help in deciding whether to go for a RCC basement or Pillar foundation for home construction. I am not a civil enginer. I want the home to be constructed on a strong foundation. I have heard from someone that basement makes the home weak in terms of its foundation. For example in earthquake home with a basement can be more vulnerable to cracks or collapse. I have zero knowledge about construction. That is why I need your help.

Should I go for a RCC basement OR pillars foundation.

My only concern is that the home should be on a strong foundation. I am planning for ground floor and in future if needed then first floor. Please guide me which way to go.

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The simplest answer would be both thins are possible with equal safety.It is only you who is to decide whether you need basement for extra space or not? because ultimately it is going to affect your cost of construction. Kindly tell in which city/area this house is going to be constructed. Also tell what type of terrain/ site grading is there. Some times providing basement may reduce your cost of backfill. So tell something about soil and site grading. Is it flat, slopy, hilly or what?

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The added cost of constraction because of the basement is not an issue. I can afford to go for it but again my concern is the saftey. Specially in earthquake. Site grading is also not an issue because only 3 feet grading is required. The surfuce is plain and does not require more than 3 to 4 feet backfill. The water level is 60 feet in the area I am planning to build the house.

It is on the main G.T Road of the Peshawar Noshehra near New City Home Residintial Housing.

If In case I decide for the basement, does only the exterior walls has to be RCC OR the inner walls also need to be RCC?

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Only exterior walls need to be of RCC. For construction purpose, U can consult the following manual. and MUST follow its practices. But remember, it is not the design manual. So you need to have a good design of your house including footings, RCC walls, band beams, and corner columns etc. 

 

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On 2/9/2017 at 10:47 AM, BilalAhmad said:

The added cost of constraction because of the basement is not an issue. I can afford to go for it but again my concern is the saftey. Specially in earthquake. Site grading is also not an issue because only 3 feet grading is required. The surfuce is plain and does not require more than 3 to 4 feet backfill. The water level is 60 feet in the area I am planning to build the house.

It is on the main G.T Road of the Peshawar Noshehra near New City Home Residintial Housing.

If In case I decide for the basement, does only the exterior walls has to be RCC OR the inner walls also need to be RCC?

I remember Nowshera has some flood history too so you might want to reconsider the basement portion based on that.

However, if you still wan to to have a basement, a semi-basement, just 4' below grade might be more in-expensive option. You can also ask your structural engineer to design a masonry retaining wall (if he can). That can save you some money. Also, things to watch out are water proofing details at the exterior face of the wall.

Thanks.

 

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Adding a basement for home construction is obviously the owner's choice. But as a structural engineer for home construction in Pakistan, I would highly recommend not to add basement. This is due to lot of additional expenses, like RCC retaining walls, waterproofing, flood control, toilet/bath expenses, ventilation etc.

If designed and constructed properly you do not need to worry about earthquake. Again, I would have added one and half additional floors from the same money being spent on basement and also forget about the worries mentioned above. Or could have spent it elsewhere like finishes, elevations etc.

And what do you mean by Pillar foundation?

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