Polished Concrete

polished concreteSo you like the idea of Polished Concrete. . . . but with costs ranging from $55/m2 to $120/m2 there are quite a few things to think about.

Slab Design and Construction

Quality of finish starts with the design and specification of the slab. That includes:

Colour

Although a standard concrete can look good when polished there is also the opportunity to make the following changes:

Aggregate Talk with your specialist subcontractor who should be able to provide a range of different aggregates.

Cement Paste In addition to the standard light grey a range of concrete colours can be provided with the addition of various oxide based pigments.

Typically if you want either, or both, of these options the slab will be laid with a layer of concrete with your selected finish as a final delivery of the pour, over a standard concrete.

Grind and Seal Finish

Suitable for indoor and outdoor concrete.

In this process the floor is generally ground twice . The floor can then be grouted (see below) followed by 2 coats of sealer to give the concrete a shiny appearance (The sealer will eventually wear and need to be sanded back and re-applied.).

There are typically between around 5 steps in the process.

An advantage of this process is that you are able to make it anti-slip by puting  grit into the sealer. Great for around pools.

Mechanically Polished Concrete (MPC)

This high end process is really only suitable for inside concrete

This concrete polishing process the floor is generally ground twice depending, as above.

It’s then grouted (see below).

A densifier is then applied to harden the floors surface.

Next is up to 7 passes with diamond impregnated resin pads to get the desired shine (the concrete itself shines rather than a sealer which could scratch off).

Finally a penetrating sealer is applied to leave a stain resistant floor that that looks and feeling like glass.

The process has between 10 – 14 steps.

Aggregate Exposure

There are 3 levels of grinding exposing various levels of the aggregate commonly known as:

  • Nil Exposure –(less than 1mm) – Very little/no stone shows on the surface of the concrete (Difficult to achieve unless the concrete has been poured perfectly)
  • Minor/Random Exposure or Salt and Pepper Look (1-2mm) – Small amounts of aggregate visible on the surface – some areas may have minimal exposure while other areas some may have heavy exposure.   – approx 1-2mm from surface.
  • Full exposure (5mm) – this is where you can see all the stones on the surface.

Grouting

Any insitu concrete will have some defects such as small ‘air’ voids or small cracks.

To get the best finish they need to be filled with grout.

With a  natural cement concrete grouting may be carried out with a cement paste in the case of a grind and seal.

If you have a coloured concrete a better grout result is achieved by mixing a latex based product with the concrete dust from the grinding procedure to get a better colour match. This procedure should always be done for mechanically polished concrete.

Summary

There are a lots of options when thinking about ‘Polished Concrete’ so make sure that you understand the options and specify exactly what you want.

 

For more information see Concrete

 

 

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather
WAS THIS INTERESTING? . . . . WHY NOT BUY anewhouse GUIDE ONLY $4

Quick Build ?

One of the reasons that people may choose a builder is the promise of a ‘Quick Build’ . . . . . but how realistic is that promise?

Getting the house finished quickly might be attractive to you so here are a couple of things to think about before you make a choice.

Is Obtaining Permits Included?

Builders will either want to say they aren’t responsible for any planning/building permit delays of over 1 month, or even exclude the planning/building permit period entirely from the period.

Approvals should be quick for a new major development subdivision and may only take around a month.

If you are building in an established area such as an single block subdivision, or Knock Down Rebuild (KDR), it can take several months.

What Are The Liquidated Damages?

Any ‘Quick Build Offer’ means nothing unless you are compensated for any time overrun!

The way this is done in a building contract is by specifying a Liquidated Damages amount.

Unless this amount is a reasonable sum (say close to what you are paying in rent) the offer isn’t really worth anything!

 

For more information see Liquidated Damages.

 

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

The House of Darth

One for all those Star Wars fans out there!

star wars conservatory

Seen on the Angry Architects Face Book Page

For more Unusual House Photos, Wins, and Fails, have a look at: What the………………….?

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

Comparing Gas and Electricity

Traditionally gas has been cheaper than electricity but with the price of gas rising this could change.

Actually comparing value for money is quite complicated so I though I would explain how to do the various calculations.

Cubic Metres to Megajoules

Gas is measured at the meter in cubic metres but you pay by the megajoule (MJ) To convert cubic metres of gas to megajoules you have to multiply by

  • The Heating value (*Typically around 38.7)

and

  • A Pressure Factor (*Typically around 1.01)

*check a recent gas bill for the actual values

The value you have calculated is the Megajoules input into your heating system. The actual output can be quite a lot less.

Gas Efficiency

To find the heat output from your heating unit you need to find the actual efficiency of the unit, which can very considerably.

No gas heater has 100% efficiency as some heat is always lost up the flue.

A basic gas heater (3 Star) may have an efficiency of around 60% while some of the 6 star units have an efficiency closer to 95%.

Once you know the efficiency you can just multiply the Megajoule input by the efficiency to get the Megajoule output/Cubic Metre

Megajoules to Kilowatt Hours

1 MJ = 0.278 kilowatt-hours (kw-hr)

Electrical Efficiency

There are two different ways of using electricity to heat your new home.

Direct, or conventional, heating or using the power to run a Heat Pump, or Reverse cycle air conditioner.

The method you choose can make a dramatic difference to the heating efficiency.

Conventional Electrical Heating

With conventional Electric heating, such as panel heaters or fan heaters things are much more straightforward.

Every kw into your house means one kw output (100% efficiency)

That doesn’t mean that overall electricity is 100% efficient, just the inefficiencies occur before the power goes through the meter.

Heat Pumps and Reverse Cycle Air Conditioning

An advantage of Heat Pumps/Reverse Cycle Air conditioning is they have a positive efficiency, they can put out more kw of Heat than the electricity that goes in.

They do this by extracting the heat out of the outside air.

Pick a good unit and you might find them 2005 or even 300% efficient for heating!

 

 

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather
WAS THIS INTERESTING? . . . . WHY NOT BUY anewhouse GUIDE ONLY $4

Will You Be A First Home Buyer In Perth?

Sponsored by First Home Owners Centre

The Department Of Finance has released good news if you are considering becoming a first home buyer, in Perth or anywhere in Western Australia.

FHOG

Changes in 2013-2014

The adjustment announced last year, in the projected State Budget for 2013-2014, included an increase in the First Home Owner Grant from the previous amount of $7,000 to $10,000. This increase is for any first home buyer in Perth, or elsewhere in Western Australia – constructing or buying a new home.

In addition, it will offer a $3,000 allowance for any first home buyer obtaining an Established Home Commence Operation from September 25, 2013. Essentially, this means that any first home buyer that signs an agreement to build or purchase a new house from that date, or has already begun laying the foundation for the building of a new house, is entitled to the enlarged $10,000 endowment.

If you are a first home buyer signing a new agreement to purchase a previously constructed home from September 25, 2013, you may be qualified for an award of $3,000 towards that purchase.

Duty Liability

As a first home buyer qualified for the First Home Owner Grant, you need to be aware that a percentage rate of transfer duty will apply if the assessment of the property falls below a certain limit. When you apply, the details of this duty will be explained in the documentation.

Other Resources

As a potential first home buyer in Perth, you should look into what other resources might be available to you to assist with your home buying funding. In addition to the funding available from the Department of Finance, there is also grant funding available from the Department of Commerce. Founded under the Real Estate and Business Agents Act, The Home Buyers Assistance Account, offers a support grant of up to $2,000.

For more information on learning how you can become a first home buyer in Perth, visit FHOC.

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

Soil Heave – Protecting the Slab

There has been a lot of talk in the Melbourne papers recently about ‘Slab Heave’ when Building on Clay so I thought I would explain how to minimise the risk during construction.

A key issue when building on clay is to avoid any extra moisture getting into the clay under the slab. causing the clay to swell, by keeping the area around the slab well drained.

This is particularly important where part of the slab is below the natural ground level such as when ‘Cut and Fill’ is required to get a level site.

Detail For Protection Against  Soil Heave

The diagram below shows what you should be looking for, during construction, to protect the ground under your slab from gaining moisture.

Protecting slab Stage 1

The key issues are:

  • The excavated surface falls away from the edge of the slab for at least 1m with a minimum drop of 75mm.
  • Where the water will not continue to flow away from the slab an Aggi Drain in a granular back filled trench should be provided. This drain should be a minimum of 100mm below the surface level of the clay and fall to a suitable discharge point.
  • Any trench in the area between the slab and the aggi drain should be topped with well compacted clay to ensure there is no easy passage for water to penetrate under the slab.
  • Roof drainage should be connected to a suitable point of discharge as soon as possible after the roofing material is fixed.

Although the requirement for an aggi drain is not as critical where the ground slopes away from the slab, it is nevertheless good practice to have one.

 

Also see Agricultural Drains

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

Stuck on Brick – Fail

Not a new house but this amused me when I saw it.
silly brick

I have never been a fan of stuck on bricks as they never look real to me. . . . . . but these have been fixed (not very securely) over a perfectly good brick chimney!

 

For more Unusual House Photos, Wins, and Fails, have a look at: What the………………….?

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

WAS THIS INTERESTING? . . . . WHY NOT BUY anewhouse GUIDE ONLY $4

Danger of Under Insuring

In a New House Insurance post I explained how easy it is to under insure a property so here is an explanation of what can happen with an under insured property.

Let’s you insure your new house for what you paid the builder, say $200,000.

Total Loss

In the case of a total loss, yes, you get $200,000, but you will need to meet demolition costs and all the other issues mentioned in New House Insurance say $300,000.

Partial Loss

But what about if  part of your home is damaged?

Say it would cost $100,000 to repair the damage, but the insurer isn’t going to pay $100,000 to repair the house, – they’ll calculate that you were only 66% insured, and only pay out $66,000. Leaving you to find $34,000.

What can make this worse is that insurers aren’t obliged to pay out the cash! . . .  they may embargo the $66,000 until you’ve come up with the rest of the money.

Major Under Insurance

If you are really under insured there is a risk that the insurer will argue that you’ve deliberately under-insured and your policy is void.

 

facebooktwittergoogle_plusredditpinterestlinkedinmailby feather