Getting the dreaded “Help my new house has flooded” phone call…
Alistair McLean
Category: Building, Renovations

Alistair: Posted on Thursday, 7 June 2012 2:03 PM

Ms M has learnt the hard way that the value of good design has nothing to do with getting some cheap plans drawn up.


The drought has broken.  Melbourne has had a wet autumn, and it looks like we are heading into a wet winter. Ms M rang Secret Design Studio completely out of the blue one wet day a few weeks ago.  She has never been a client or had any previous contact with Secret Design Studio, and I was pleased to hear from her, even though she had problems with her current development and was looking for help.

Quite a few years ago I had first met Ms M, as she was a pre-existing client of a town planning and architectural consultancy that I worked for, way before Secret Design Studio had even been conceived.  I quite liked Ms M as she was a go-getter, and was building up a small portfolio of townhouses and units.  She was a repeat client and her first development was a pair of single storey terraces. Based on the success of those I was responsible for the design for town planning of her second development.

She had purchased a block of land with a small house in a pleasant leafy street in Ringwood which was ideal for redevelopment.  Towards the front of the block, was a small, slightly run-down 2 bedroom weather-board cottage that had seen better days, but was still habitable.  The block sloped steeply down towards the rear boundary, but the steepness was concealed by the overgrown and neglected garden.  It may have been a deceased estate when Ms M had purchased it, as the garden had certainly been let go, and I seem to recall blackberry bushes when I first inspected it.  The density of blackberry bushes are always good at disguising slope.


Ms M’s intention was to give the front cottage a quick lick of paint with a cheap and cheerful renovation. Then move tenants into the front cottage as soon as possible, while the town planning and building work happened to a new 3 bedroom townhouse to the rear.  The block was about 48 metres long, and the existing house was offset to one side, which allowed a decent driveway on the eastern side to access the new garage for the existing house, as well as the proposed unit with its double garage.


Unfortunately the slope of the site combined with council’s height restrictions was problematic, and would need some careful design consideration to get it through the town planning issues.  Over the length of the lot (48 metres) there was a fall of 4.2 metres.

When working with steep sites I like to work with split level solutions, similar to those commonly used by Australia’s most iconic project home builder Petit and Sevitt.  Feel free to refer to Secret Design Studio’s Petit and Sevitt blog posting at


The principles of a split-level home do take a bit more thinking and design consideration at the early concept stages, but they provide many advantages for the steeply sloping site if executed well. Split level solutions usually provide a closer connection with the garden, minimize the costs of cut and fill, work better with the height limitations imposed by the town planning regulations, and provide visual interest internally.

When outdoor space is at a premium, such as in a dual occupancy development, it is good to try and minimse the need for ugly (and expensive) retaining walls as much as possible. The small footprint of this rear unit had a fall of ground level of 1.4m across the building, so a split level solution was the way to resolve this 1.4 metre drop, and avoid the problem of connecting the garden to the house with long flights of stairs, and tall retaining walls.


Pictures above and below – Some bad examples of ill-considered design in regards to the relationship between indoor and outdoor living areas – not the work of Secret Design Studio.


Pictures above and below – Some bad examples of ill-considered design in regards to the relationship between indoor and outdoor living areas – not the work of Secret Design Studio.


Unfortunately the split level solution is not used as often as it should be today, especially with the major builders.  Split level homes are harder to design well, and they take more time and experience (and cost) to get right.  The major builders prefer to cut-and-fill the site to provide a flat slab for their standard product, which is often to the detriment of the landscape and the relationship between the house and garden.

By transferring the additional building cost that a sloping site requires from the cost of the house construction to the ever-flexible site costs means that everybody should be happy.  The standard builders product remains close to the standard display on a flat slab and they haven’t needed to spend any money on design to adjust their standard product for the sloping site, so the cost of the house component remains close to the original quote.  However the project cost, which includes the retaining walls for the cut, and deeper footings for the fill areas has increased, but these are easy to get approval from the customer as they are required by the engineer.

While the design for Ms M’s townhouse was unconventional the ground floor plan worked really well with spaces defined by the changes in level.  The entry level consisted of an entry hall, a powder room, a living room, a small flight of stairs going down to informal living, and another flight leading up from the entry hall to the first floor with secondary bedrooms and additional north facing living area.

The lower level consisted of a large north facing family room, which opened at the rear to a good sized courtyard, a master bedroom suite, a kitchen, and a laundry.  From the laundry there was a small flight of steps leading up to the garage – and this is crucial – the garage was on a higher level than the laundry, kitchen and family room.


Plan above shows the original town planning drawing with raised threshold between garage and laundry steps.

The value that a good designer can contribute to any project is the years of experience that they bring to the table. An inexperienced draftsperson often cannot see the potential issues. In this project Ms M learnt that you get what you pay for.  This is especially true when you go with the cheapest option rather than the more expensive option that has higher value in the experience and professionalism behind it.

For Ms M’s project I had had concerns about the possibility of flooding while completing the design development stages, and I always like to take a belts and braces approach to minimize this type of risk.  Unfortunately some “flooding” is less an act of God, but more a case of incompetent design, with an inevitable outcome. This means that when you have a 30metre long driveway that has a fall of 3m over the length before it reaches the garage, that you don’t rely on a single drain to catch all of the water at the garage door!


In the town planning drawings I designed two features that would reduce the risk of flooding. The first was to level the driveway out for a 3 metre length where it widens out, about 4 metres before the garage.  This would assist in reducing away some of the momentum of the run-off, and allow some of the water to be redirected into garden beds and away from the vulnerable garage door.  This is the same principle used in theme parks with water slides.  At the termination of the slide it levels out to reduce the momentum of the rider.

However my main concern was that if the storm water drain blocked, then water would flow into the garage, then through the internal door at the back of the garage, down the steps into the laundry and into the kitchen and family room.  In a more conventional design the access between garage and house usually has a step up at the threshold, but due to the split level nature of this design the internal access threshold was stepping down – and water always runs downhill!

My solution was to provide a step up from the garage to a small landing at the door threshold, then add another step to the stairs going down to the laundry, to provide a fool-proof solution.  Any water that flowed into the garage would then be stopped at the step-up, and should flow out the rear external door of the garage into the garden rather than the laundry and kitchen. In addition I would have provided a lip to the edge of the slab where it was adjacent to the family room, but this sort of detail is not required for town planning drawings, and it would be included in the working/construction drawings.

From the lodgement of the town planning application I lost track of the project.  I moved on to other opportunities, and founded Secret Design Studio, and the application went through council, fairly smoothly it appears, and received a town planning approval as I had designed it.


I occasionally wondered how Ms M, and her growing property portfolio was progressing.  I had always meant to drop around to see the finished unit to see if it had turned out as well as planned, and if council had required any changes to my design before granting approval.  I did not want to contact her, as to the best of my knowledge she was still a happy client with my previous employer, and I knew that they would be looking after her.

And then I received the panic phone call from Ms M.  She knew that I had long left the consultancy where I had designed her townhouse, and she had found my name and number via the magic of Google.   She told me the worst thing that one person can say to anybody involved in building design –  “Help my house has flooded”.

The townhouse was nearing completion, there had been lots of rain, and not only the garage, but the laundry, kitchen and family room had flooded. I asked her to send me the construction drawings so I could refresh my memory on the design, as it had been a number of years.  The first thing I noticed was that the construction/working drawings had not been completed by my old employer. At first glance the drawing sheets looked neat and professionally executed, with proper lineweights, text and were easy to read.

Apparently Ms M, had finished making use my previous employers services shortly after I left, as they were “too expensive”.  I was a little surprised to hear this as the service that was provided was always professional and the team was well experienced in this type of documentation. Their fees, which while not the cheapest, reflected the value of the teams professionalism and years of experience with this type of project.

I thought I should find out a bit about the company that had completed the construction drawings and found their website, where they promoted themselves as draftsmen and building designers.  I was very amused that they had a tab called “Downloads”, on their website, with only two documents available for download.  The first was a “Copyright Information Sheet” from the Australian Copyright Council, which provides a brief introduction to copyright issues for builders, draftspeople and architects, and for those that engage these services.   The second document was the same set of plans that Ms M, had sent me of the townhouse that I had designed for her all those years ago, that was being promoted as an example of their work!

I asked Ms M what she had thought of their services and how much she had saved.  Well she had saved quite a bit in the fees, in fact the services were only 25% of the fees proposed by my previous employer.  However she was not happy with the errors that had been made.  The builder had discovered after construction had commenced that there was not enough head clearance to the stairs up to the first floor and the redesign and rebuild cost had been considerable.  The new man, “Mr 25%”, had said that it wasn’t his fault as that was what was on the town planning drawings.  He had only drawn one sectional drawing through the townhouse and it didn’t include the stairs, which is always good practice to confirm correct head clearances.  In addition there was no stair detail in the eleven sheets, and a house of this size would normally cover at least 15 or 16,  A3 sized sheets in the working drawing set.

From Secret Design Studio’s perspective, Mr 25%, as the man responsible for completing the detailed construction/working drawings, and building permit application,  should check that the head clearances work, rather than misinterpreting a less detailed town planning drawing – it needs to be right before it goes to site.  I started to wonder what other elements may be missing from this cheap set of drawings?

Apparently Ms M had a fairly heated conversation about the issue and her additional costs to overcome his oversight/neglect.  “What do you expect for 25% of the fees that the others quoted?” was Mr 25%’s response!  For some reason when I heard about this I started to think about peanuts and monkeys.

One afternoon in the same week I was in the Ringwood area for one of Secret Design Studio’s Mid Century Modern clients, so I rang Ms M to see if I could drop around to have a look at the site and the flooding.  I wouldn’t normally do this for somebody that had never engaged Secret Design Studio, but I did feel sorry for her, I was curious how it could all go so wrong, and what I could learn from the inspection for my own future reference.

The causes of flooding were numerous, and obvious.  The townhouse was nearing completion, with kitchen cabinetwork installed, and awaiting final painting, tiling, carpeting and floating timber floors to be installed.  The family room floor was awash with a couple of millimteres of muddy brown water lapping around the freshly painted MDF skirting boards.  The garage and laundry had been similar, but had partially dried out leaving damp patches and a thick muddy stain across the concrete. The long driveway was a quagmire, with no concrete poured, and no drainage.  The gutters were attached, but no downpipes or stormwater connections.

In fact there was a pile of colorbond downpipes stacked in the mud, that had been installed, and then removed, and were being replaced by PVC pipes to feed the closed water system to the rain water tanks.  It appeared that the colorbond downpipes had been removed just prior to the week of rain, so all of the water collected in the roof gutters, just ran out and soaked into the clay soil around the perimeter of the house. When the clay could no longer absorb any more roof run-off the flooding had started. Unfortunately the 75% cheaper drafting fee had not included nominating the location or type of downpipe, and somebody had made the wrong guess in ordering the downpipes – I wonder who paid for the replacement cost?

With a wet week, no drainage, and no downpipes connected it was inevitable that the garage at the bottom of the quagmire driveway would collect water, but where would the water go?  The raised threshold step for the internal access to the laundry, which had been clearly documented on the town planning drawings, had gone! Mr 25% had decided that while he couldn’t check the clearance to the main stairs, he could remove the “uneccessary” step up, then step down into the laundry, so half the water from the 30m long unsealed driveway went through the garage to the laundry doorway, down the steps into the laundry – and some even flowed through into the kitchen to puddle around the baseboards of Ms M’s new kitchen cabinetwork before drying out.


Why hadn’t the water flowed out the rear external door of the garage into the garden? A standard timber external door frame was used in this doorway, with a timber door sill sitting on the garage slab.  This timber door sill had done a great job of damming the water flow and redirecting it to the adjacent laundry door that had no sill, where it could flow down into the house. This external door would have been better without a timber sill sitting on the garage slab, as without an eave overhead it will be exposed to rain, and will rot out in time.  A better detail would have been to use a door frame without a susceptible timber sill, and perhaps detail the edge of the slab for a doorway, or a brick sill?  However this sort of design detail takes experience to know about, and a little bit of time to draw up and detail, and this type of care and professionalism was not covered in Mr 25%’s cheap fees.


Picture above is a neater solution to a rear opening garage door and doesn’t use a standard timber door sill.

So where did the other half of the muddy water go from the garage?  Over the edge of the slab (without a lip), and down the edge of the slab behind the timber stud wall, then under the MDF skirting and across the family room floor, where it pooled. The plans call for a timber floating floor to be installed to the family room, so I hope that the builder allows time for the slab to dry out completely before the timber floor is installed over a damp slab.

Despite the smell of drying muddy pools of water, the feelings of dampness and mustiness, Ms M’s townhouse was built as I had designed it, and worked very well for the site and its steepness.  The split levels for the ground floor worked well, the family room and the upstairs living room were flooded with northern light, the master bedroom had a pleasant garden aspect,  and the family room door had easy access to the rear courtyard.  As far as I could tell there had been no changes required by council from my original design, which pleased me..

One of Secret Design Studio’s favourite Frank Lloyd Wright quotes is “You can use an eraser on the drafting table or a sledgehammer on the construction site”.  Building (and demolition) costs are very expensive compared with design and documentation fees.  What Ms M saved on the fees for working drawings, she had more than spent on a stair rebuild, downpipe replacement, skirting board replacement (MDF and muddy water aren’t friends), and cleaning up mud.  Unless she pulls down the wall between the family room and garage she will never clean up the mud that is caked onto the edge of the slab behind the wall.  But apart from the financial cost there is also the stress cost which I had heard through her voice from her initial “Help my house has flooded” phone call.

Despite this disaster Ms M is very lucky.  There didn’t appear to be any damage to the kitchen cabinetwork,  which was in a glossy two-pack finish.  Her carpet and floor tiles had not been laid – the carpet would have had to be replaced if it had been waterlogged with muddy water.  It could have been much worse if the house had been occupied with damage to furniture and electrical items. While most insurance companies cover Acts of God (if you are not flooded in Queesland), do they cover inadequate detailing that leads to flooding?

Ms M’s town house now has all of the downpipes properly connected.  The driveway has just been poured, including the flat go-slow section, and additional storm water drains have been included. Nothing can be done about the missing raised laundry door threshold, or the poor sill detailing to the external rear garage door, so let’s hope that the new occupants remember to maintain the storm water drains from blockages.

I have included some excerpts of the working drawings that were completed by Mr 25% to illustrate this blog.  I am sure he won’t mind me using the freely available .pdf download of this project design from his company’s website.  According to his other download, the “Copyright Information Sheet” from the Australian Copyright Council, the copyright of the design actually belongs to my previous employer – I just love the irony!

The lesson that I hope Ms M has learnt is that there is value in well thought out and considered design, and design decision-making.  Every line on a set of plans should have thought and a decision behind it, and the experience behind these decisions needs to be paid for, which should be reflected in appropriate fees.  The value of a well thought out set of plans is not in the lines and paper, but in the thought behind the lines.  In this case a set of plans, that looked professional at first glance, had some serious omissions.  Inexperience and cheap fees also cost, both financially and in stress levels.  Secret Design Studio wishes Ms M the best with this development and her future development endeavours, and hopes that she will not be needing to spend money on a sledge hammer as she “economised” on her design and drafting fees!