Asalam-o-alikum!
I am constructing a house in bani gala, islamabad. The plot is situated on a hill that is about 100 feet height from the road. My question is that during the excavation of foundation a week ago the soil was soft primarily due to the rains i think. Our contractor thought it to be dangerous so instead of digging up only the marked area for the foundations he dug up the whole area and at some points the dept of the whole crater that he has created is 8 feet. So we are clueless how to proceed from here. The soil after getting a few sun shines seems quite intact and does not have that much moisture now. Now filling up the plot again and raising the level again is another cost and resource issue. I have a lot of stone for stone masonry that is lying in the plot. I want to know if its wise to do the foundations in stone masonry so that we can achieve some height and then continue on with the raft and pillars once we reach the desired level or any other way to save cost. Any help from the experts would be highly appreciated. Thanks! Junaid
AOA,
Very strange situation. First of all,Is your contractor an expert in his field because only a novice can make such a mistake.
But any how:
Filling again is not at all suggested because than you would have to do compaction..
In olden times the base was made of stone masonry instead of steel and concrete.which has a proven track record.some 100 years old building are still standing strong.
But i dont think you will find an expert in stone masonry now days.The other option is to use cement and wiring for stone masonry (depending on location)to make a solid base than a raft would work.Keeping in mind that its stone if not bind together properly than may be in future when the plot next to you is being dug for construction it may hamper your home.(God forbid)
the last option is to make a raft than buniyad to the road level(in your case 8 feet) than do the filling inside.This option is most common now days.
Please dont take risk and get structure engineer advice to avoid any future problems.
Regards
H-T and DSA, actually I think Junaid thought it was a hill on his land but in fact it is not a hill - it is just a pile of mud which had hardened a little with time.... But still it is just a pile of earth not a hill so it cannot withstand the weight of a concrete brick house.
He should just assume that the plot is at road level and start digging the foundations down from road level and dig deeper than usual. Then put in some extra brick and steel work into the foundations.
What do you think guys?
No it will not work and if it is pile of mud then it can create problems…Not recomended to build a house there…
@Junaid. It's better to consult a structural engineer. I know an army man in Bani Gala who made his house on Korang road and in rainy season, his house was shaken due to erosion of some soil under it. It was a filling area.
Also, go to google earth and target you proposed home plot. Go historical imagery and rewind it back to few years. See if the hill was still there or its man made hill. If the hill is for a fairly long time than you are safe. You have a solution for it.
Make foundation like Murree houses are constructed. Go deep for column's base only. Make columns upto plinth beam and connect all these columns through plinth beam and make it a uni structured foundation.
All this is from a lay man so don't trust me. Consult a structural engineer and get expert advice. But this google image thing will do the trick rather unconventionally. Such facility is in computer's google Earth and not in mobile devices.
@ paki 1
If what your saying is true about a pile of soil than yes building a house there would be very risky.
i agree with DSA consult with any engineer who can visit the site and ask him to preform soil test atleast 15 feet deep....
Since you have dug 8 ft deep already, I would personally do a concrete foundation at least 1 ft deep and then start brickwork on top of that. It is expensive to cover the floor with thick concrete as a base but in the long run it will be a strong foundation.
I request to ppls please please dont hire any un skilld person for construction.alway hire well qualified and expeirenced ppls.
A qualified structure engineer is the nessery part of whole job.
And i also request to all contractors pls dont take the risk of ur career,do the job under qualified consultants and avoid the future problems.
There is no harm in doing deeper excavation, particularly where there has been filled area. However it is expensive but you will get a stronger foundation.
Dear
just do a soil test of your plot, take advice any local structure engineers which might be attach with any architect. So visit his office and get his opinion. Dont take risk. And your labor is not skill. Change your labor contractor as well.
regards
faheam
03217867889
Thanks every one for ur valuable feedback. Its on a hill and its the same hill Imran Khan’s house is located. Have shown to some structure engineers the soil was soft as the plot is downhill and some artery of a stream maybe passing or just the rain water may have accumulated for a while. The other half of the plot is solid rock.n Going to fill the plot with (ghera “stones from riverbed”) then do compaction and then the raft and rest of the foundation Insha-ALLAH!