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Muti Ur Rehman

Comparison of Masonry and Raft Foundation for Houses

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Assalamu Aalikum,

Hi, I am a new member. I have a plot measuring 30*70 feet. Most of houses being built here (in Rawalpindi) have masonry foundations (a pyramid of bricks on PCC or sometimes the PCC layer has three to four iron rods of size 3/8 or 4/8  in this "PCC" layer. I want to make a raft foundation instead of masonry foundation but the cost seems to be high. I want to ask if I make a raft  1 feet thick and put a single mesh of center to center distance  12 inch. Even this will cost more but if it gives more strength then I want to  go for this. Would such foundation more durable and strong?

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2) I want to dig three feet to make a one foot thick slab. After the mat/ raft  I want to simply start 9" bricks layers. For column I will make a footing on the slab but the footing will be only concrete with only bent rebars. (3) I will not make plinth beam, but put few inch DPC. (4) At windows/ doors level I will make a continuous beam of four iron rods. On the roofs I will make complete beams. Would this structure more durable then masonry foundation building??? Actually I want to optimize, be economical and want a strong building. I want a two story building with mumty on this plot. Thank you.?

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Raft for a house is overkill unless you really need it. An example is where the house is being built of area that is a fill and the ground might settle. If the construction in your area is masonry, stick to it. You won't get any benefit out of a raft. 

 

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why you are giving Raft for a two story building?

Rcc material will definitely give higher strength , But to create a cost analysis of the two materials carry out quantity survey and compare with your market price

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