Concrete Slab

The concrete slab has been poured and she's a beauty. The whole day was cloudy and overcast which meant the slab avoided direct sun while it was curing.

The surface is covered in a white powder. The builder says this is salt (?) coming out of the concrete, and after a pressure clean will come out much darker.

You can see the bathrooms, ensuite and laundry have been lowered 20mm into the slab, so when they are tiled they sit flush with the rest of the ground floor.

In this detail of the slab you can see the edge insulation, the plastic sheet, the burnished finish, and a groove to encourage cracking. The slab will crack, it's just a matter of where, so you try and encourage it along lines where it doesn't matter. This line is underneath the ensuite/bedroom wall.

Slab Heating

Footings and sewerage pipes have been installed. Now the various preparations for the concrete slab pour are underway.

This is the hydronic in-slab heating. The 30kW gas boiler is outside with the hydronic manifold inside the laundry cupboard. This will double up as a drying cupboard.

You can see the slab reinforcement mesh. The engineer has specified slightly thicker mesh than you normally use for residential slabs, because of the sloping block and the height above ground.

The outer course of bricks is a veneer. The inner course transfers the weight from the slab down to the footings. Underneath the black plastic is foam insulation.

The builder now needs to wait for a good day to pour the slab. Too hot, too cold, too dry, too wet, or too windy, will all mean an inferior slab. This is going to be a burnished concrete finish, so it needs to be just right.

Foundations Laid

The builder wastes no time putting in the footings for the concrete slab.

Until now I've only seen the house in diagrams and 3D renders. The footings give me a much better idea of the size and layout. 

The footprint is larger than I expected. The builder says that the house will seem even larger once the walls, roof and plaster is finished. I was aiming for modest. I think I've missed that target.

Demolition Time

The past few months have been a frustrating bureaucratic exercise. Without going into too much detail, here are some warnings for anybody considering a knockdown-rebuild.

• Banks don't like architect designed homes; I think it's fear of the unknown.
• The local council's only purpose is to make your project difficult.

But after several months I finally have approved plans, certification ticked off, a builder onboard, construction diagrams, and the total price is still within budget.

So without further ado, here is the demolition of the old house.

This is a 20 tonne excavator. 

The demolition seemed to take about 15 minutes. But the excavator needed several hours to load all the rubble into a convoy of trucks.

It was an odd mixture of emotions watching the house come down. A little sadness to see my former home destroyed, but mostly uncertainty as to whether I'd made the right decision.

Too late to back out now!

Experts Only

A knockdown-rebuild is now looking more likely than renovations. The options are a project home, or a unique architect designed home. I approach TT Architecture to get some rough drafts. Then if I don't like their design it's only a few $k lost on drawings. No big deal.

Needless to say, they hit a home-run with the very first draft.

Wow. That's great. The TT design has two pavilions. The front pavilion has the main bedroom and study. The rear pavilion is for kids bedrooms and living room. The corridor between them holds the utility rooms such as bathroom and  laundry.

This is the upstairs for the front pavilion. This area includes the dining room, family room, kitchen, scullery, and decks. 

My favourite thing about this design is the orientation on the block. Rather than being square to the street, the house is angled to face the sun. The angle creates four outdoor areas which are "tied" to the house through windows, doors, and decks.

This integration of the outdoor areas with the indoor rooms finally convinces me that a knockdown-rebuild is the best option.

Drawing a Blank

I've sketched a few ideas for new layouts. This first layout aims for minimal change. The third bedroom is now the main bathroom. The kitchen and dining room are swapped. Several internal walls have been removed. I'm not happy with this sketch; the house still feels like a maze.

This second layout puts the living areas on the North and South for better light. The utility areas move to the East and West. The galley kitchen isn't spacious but it is practical. This layout has a much better separation between guest areas and private areas.

This third layout is my favourite. The L-shaped public area includes the kitchen, dining and living rooms. The bedrooms are north-facing and clearly separated from the rest of the house. The major problem with this layout is the amount of change involved; I'd have to completely gut the house & relocate all the plumbing, electrics, and internal framing.

And there's the dilemma in a nutshell... major renovations are difficult and disruptive. I don't have the skill or enthusiasm for renovations so I'm going to have to hire a builder anyway. And no matter how much I rearrange the internal rooms, that won't solve big problems such as orientation on the block.

Evolved Design

I've drawn up the house in Sketchup so I can work out the renovations. One internal wall, a leftover from a previous extension, is load-bearing but everything else can come down. There's a disconnected brick chimney in the centre of the house that needs to be removed.

The house layout has evolved organically over 50 years. There have been a few mistakes made, e.g. the kitchen gets the best light; the bathroom is in the centre of the house, the second bedroom is a corridor to the main bedroom, etc.

These layout problems can be solved but only with some major renovations.