Building A Duplex

Hi

I have a block of land that I would like to build a duplex on. It slopes slightly to the side and possibly gently away from the street.

I have been talking to project builders to arrange site inspections however I have hit a snag already!

It seems that drainage of storm water has become the make or break of whether I can even get a duplex built on the land. Apparently if my land is not sloping towards the street then the storm water has nowhere to go - unless I get an easement built through a neighbours property to carry it away. (which I hear is unlikely to be agreed upon)

I have seen lots a lots of duplexes built on all sorts of sloping blocks and they couldn't all have had to build an easement on neighbouring land!

Is anyone able to shed light on the drainage issues for duplexes and solutions?!

I'm also looking for recommendations on companies to build a duplex with. I have heard a lot about variation nightmares and poor site supervisors ruining the jobs. i'm hoping I can find a company that will make this process as easy and worry free as it can be!

I look forward to any info you can offer to help me along! :confused:

Regards
 
Hi Duel,

Sounds like you have a major problem. You do need to drain the stormwater to the council drainage system. Therefore it's to your roadfront or through a neighbouring property. You may be able to have a charged system if your site is not too slopey. Your tank overflow height would need to be a certain height above the gutter - but ground level may be below. Check with your council planning dept or a local plumber who knows the specs. You need to design this one carefully or you will be in for a major disappointment if the DA is knocked back. :)
 
Thanks for your help Rockstar. Does this drainage issue also apply if I were to just build a single house on the land? I'm wondering whether it might be easier to go down that path if this duplex drainage gets out of hand!

Regards
 
With a single house you should be able to create a drainage pit to drain water into. We have one on our house as it was impossible to get the stormwater to the street. They don't allow you to use this method in dual occ in our shire. Check with your local council planners
 
Seems funny.

The catchment area on your block will be the same....whether it is vacant or whethre you have a duplex on it.

Currently, if it is sloping away from the street, I assume all current overland flow will be going to a neighbour.

Why would this be any different.

You are not constructing something that adds more water or rainfall to your plot?

Maybe a big water tank for each duplex might be an idea (which gets connected for dirty water operations.) This would save some overland flow issues. (i.e. when water tanks aren't full)

Interesting to hear outcome.

Cheers,

F
 
I've dealt with quite a few NSW development applications where people have been in your situation and have had to get an easement over some of a neighbours land. I have had one applicant who paid about $17k for the priviledge and also one who could not get access and had to build his site up so that the fall went to the street (it was a near flat site). This would not be an option for you, it seems.

So, you will have to get an easement or pray that the Council will allow pump outs (most dont).

Having dealt with this issue via my planning jobs, I would always make sure any site I wanted to develop in future sloped toward the street. Neighbours have you over a barrel otherwise.

BTW, the guy who said yes to an easement was a developer who was building on a neighbouring site, all the "no" answers have come from "mum and Dad owners" who generally, in my experience, take great delight in thwarting anyone with the guts and ambition to create something of value next door...the whole "jealousy of anyone getting ahead" thing....

Good luck.
 
Howd this turn out?

Im in the same predicament. Though im hoping to build 4 on my lot and and theres a drainage easement at the back.
 
I currently have the same problem on my block.

Slopes away from the street, but wish to build a duplex. I have been advised by council that if it was a single dwelling drainage would not be a problem but for the duplex I have the following options:

a: Consult neighbours for an easement.
b: Consider building up the ground area to slop towards the front to a maximum of 1 m.
c: Submit a contour plan by a Surveyor to an Engineer to offer an alternative

So far for me option c: is worst case as I do not think the Engineer will be able to help me.

I will be over the 1 m requirement for the build up of the block.

I will be going for option a: currently one neighbour has declined another is considering the request (for a trade I will supply an upgrade of X on your house for you to give permission for the easement).

I am surprised you are assuming the neighbours will decline your request without asking the question.

I am in Queensland so my council requirements may differ from yours.

Cheers,

Fourex.
 
I currently have the same problem on my block.

Slopes away from the street, but wish to build a duplex. I have been advised by council that if it was a single dwelling drainage would not be a problem but for the duplex I have the following options:

a: Consult neighbours for an easement.
b: Consider building up the ground area to slop towards the front to a maximum of 1 m.
c: Submit a contour plan by a Surveyor to an Engineer to offer an alternative

So far for me option c: is worst case as I do not think the Engineer will be able to help me.

I will be over the 1 m requirement for the build up of the block.

I will be going for option a: currently one neighbour has declined another is considering the request (for a trade I will supply an upgrade of X on your house for you to give permission for the easement).

I am surprised you are assuming the neighbours will decline your request without asking the question.

I am in Queensland so my council requirements may differ from yours.

Cheers,

Fourex.

Hi mate,

what you have is a very common issue when the block is sloping towards the rear neighbours.

1) the best option is to talk to your neighbour that is affected and try to get their permission. i dont know your situation but from my experience you usually only need permission of only one neightbour (the one that is being affected by your proposal). we have had experience when adjoining neighbours were demanding exorbinent amounts of money for their consent.

2) on one of our projects in Brisbane, we had the neighbour objecting to the proposed duplex and there was no way that they would give us permission to go through their block for drainage. We consulted an engineer and they designed a onsite drainage system that did not affect the adjoining neighbour. the DA got approved no worries.

obviously try first for the cheaper option.

i hope it helps
 
Hi

From what I have found out it seems the front half my land slopes to the street and the back half slopes to the rear - so apparently it wont be such a big deal... (one company suggested to build up the land and another company said building up the land is not possible. so lots of diff answers!)

Also, I have been recommended NOT to get am independent contour survey done as the project builder will do his/her own anyway (hence I would pay twice)

I have spoken to a few companies and most have said that you can put a duplex on any block - they just need to come up with the solution to the issues (like drainage) at the time. Could be sales talk?!

Anyway I''ll let you know the drainage out come when it comes time...

I have got a rough quote from a project builder which has quoted me approx. 200K per dwelling including medium finishes. PLUS approx. 100K in council and other costs to get it built. IE. total approx 500K all up.

I originally had a much lower budget in mind but have not been able to find anything decent with a reliable builder (have read many online reviews). I am very happy with this design and finish however I am very confused as to why it would cost 100K for extra costs for council.

I know that MASTERTON charge approx 400K for their duplex but then would add the council fees etc but I do not know what this is so I cant compare..

Does anyone know if this 100K sounds right? I've spoken to friends but they all have different opinions. I thought it would be something like 40K...

Im thinking I should ask for a break down in writing for what this money covers. I guess my main concern is whether to trust the salesman! Also, a friend of mine has suggested I add a clause to my contract that states I do not pay anything if it is not DA approved? Has anyone done this??

Basically I just want to make sure I am not getting ripped off with "mystery" costs.

Any advice on how to handle this first pricing stage would be appreciated!
 
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Hi Duel,

Good to see that you are persisting with the development. Project builders often quote prices for the house construction without site costs. They cannot be determined until they do a contour survey and soil test. They may be including this cost in the extra 100k? Council contributions and strata costs should be under 50k depending on the scale of the project. Site costs could be 10 - 20k per dwelling depending on the site. Variables include soil type (affects footing or slab design), distance from services, cut and fill, existing vegetation, access, etc.

Get some clarification from your sales consultant regarding what your quote exactly covers and what it doesn't cover.

All the best with it, :)
 
Trust me, this is a minor problem and can be rectified. And you'll have heaps more. But patience and persistence is profitable.
Rainwater tanks are a solution. Plus have a tank that will collect the excess water and pump it back to the street. Its a simple solution and doesn't involve neighbours. A friend of mine did this and Brisy council accepted it.
As for cost. Not being a smart a....e but have you got multiple quotes? Try as many large contract builders as you can. Doesn't matter if the walls are crooked or a few things aren't spot on. The valuer looks at size, fixtures and fittings and comparable sales. The beauty of large project builders is they usually have a plan that fits the block, is code compliant, and can get through council ASAP with minimal costs.
 
duplex

hi raymond here.i am building to town houses on my block.my stormwater flows to the front of my block.i bought a laneway from coucil 15years ago.my neighbours stormwater flows in to the lane there in no easement there so council wants me to put my neighbours stormwater in and put an easement on my property for the neighbours stormwater and gift it to council.all at my exspense is this normal or should council compensate me.
 
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