Cost to rebuild a 2.5 storey house

[petetherock 13]

2 hours ago, snoozee said:

My wife’s friend’s parents place had their wall collapsed when their neighbor tore down their house and rebuilt. 
when my house was rebuilt, the low party wall with my neighbor on my detached side collapsed due to soil movements from the excavation from my side.

I think whether can add on structure on the top depends on how the existing structure and foundation was designed. If the structure had been designed with provisions for additional attic in mind including the RC floor slab already cast during initial construction, then adding the attic structure ( columns, beams and roof) at a later stage might be possible. But if the house was designed just for a 2 storey house and want to add on a full RC floor slab and roof later, I don’t think this would be possible. 

Wow, hopefully the house itself wasn't affected?

Re attic level: Thanks, I was put off by the price - 150k back then, so I went with a pool instead. The builder said the foundation were good, so when they dug the pool, it was simple. They also braced the walls and despite some heavy rains, the build was done in a month or so. 
But they did not dig very deep. 

 

[3Cube 9]

Just my personal opinion on the issue at hand.

Whenever the Professional Engineer design a structure, there is a safety factor. Maybe I'm wrong but I remember I was taught this is usually a factor of 2 or more. This means, THEORETICALLY, the building structural elements can take up twice the design load.

Having said that & for structural safety consideration. this does not mean that stacking up another floor is implied to be acceptable. This should be the concept even when the scenarios is that the structure was design with intended consideration for future "stacking" or addition of floor or floors.

 

Point number 1:

In the past, I had involved (before I started my own construction firm) in various A&A jobs where the Professional Engineer, engaged directly by the property owner, simply just added (allowed by the regulation back then) steel beams, concrete / steel bars reinforcement, etc before stacking another floor (constructed with combination of steel beams & concrete reinforcement).

In such cases, leakage usually occurs due to the nature of the work. Hacking of the old concrete is required in order to form the joint for the strengthening added beams, columns, etc. During hacking, the old concrete surface is vibrated to break the concrete. Hence cracks appear. Nobody will be able to control the extent of the crack. It maybe hairline cracks which will enlarge over time which eventually leads to leakage, sometimes at weird spots far away from the construction joint.

Point number 2:

The safety factor to the entire structure that I've mention above should remain status quo after addition or stacking is done. This should never be perceive as overkill. Due to time factor (ie: from completion of old building to start of new extension or addition) & records accuracy, the structural calculation might be flawed.  Worse case scenario you might end up with a lower safety factor than intended.

My thinking here is based on "Murphy's Law" which states:

"Anything that can go wrong will go wrong"

"If everthing seems to be going well, you have obviously overlooked something"

Better to be safe than sorry.

 

In closing, these are some of the reason why my company will only focus on total demolition / rebuilding & minor renovation works.

Edited July 4, 2021 by 3Cube
added words

[snoozee 98]

4 hours ago, petetherock said:

Wow, hopefully the house itself wasn't affected?

Re attic level: Thanks, I was put off by the price - 150k back then, so I went with a pool instead. The builder said the foundation were good, so when they dug the pool, it was simple. They also braced the walls and despite some heavy rains, the build was done in a month or so. 
But they did not dig very deep. 

 

The contractor fixed back the collapsed wall and my wife’s friend’s parents are still staying in the same house now. 

for my case, the low party wall which collapsed was removed by my contractor and redone properly together with the wall on my side. 

[Topline 1]

21 hours ago, snoozee said:

The contractor fixed back the collapsed wall and my wife’s friend’s parents are still staying in the same house now. 

for my case, the low party wall which collapsed was removed by my contractor and redone properly together with the wall on my side. 

Do you have to pay to fix your neighbour's wall? Or the contractors?

[snoozee 98]

1 hour ago, Topline said:

Do you have to pay to fix your neighbour's wall? Or the contractors?

no. it's at my contractor's own cost.

[3Cube 9]

18 hours ago, snoozee said:

no. it's at my contractor's own cost.

Most of the time, the 3rd Parties Liabilities clauses in the Contractor's All Risk Insurance Policy (to be procure by the builders before contract commencement) will apply in this scenario.

Say the cost of the repair as $X. The Excess in the insurance is $Y. The builder will claim from the insurance company $X - $Y. If the repair cost is less than the Insurance Excess, then the builder will do the repair themself.

[ColourPen 0]

On 7/4/2021 at 6:45 PM, snoozee said:

The contractor fixed back the collapsed wall and my wife’s friend’s parents are still staying in the same house now. 

for my case, the low party wall which collapsed was removed by my contractor and redone properly together with the wall on my side. 

I guess having the contractor fixed back the collapse is expected and the least that can be done.

Did the contractor alone manage the affected neighbours or did owner also speak to neighbours? Wondering how best to manage neighbourly relationship in such scenarios.

[snoozee 98]

1 hour ago, ColourPen said:

I guess having the contractor fixed back the collapse is expected and the least that can be done.

Did the contractor alone manage the affected neighbours or did owner also speak to neighbours? Wondering how best to manage neighbourly relationship in such scenarios.

not sure about my wife's friend's family.

But I spoke to my neighbour and apologised for the inconvenice caused to them.