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Waffle slabs

Hi We are building a house and the builder has an M slab as the base inclusion. The soil report has rated the land saying it needs an H2 slab. Our builder has installed a 4c Waffle pod slab. Does anyone know what the comparable difference is between H2 and 4C waffle slab? Are we in trouble with our build or are they the same rating? Any help would be greatly appreciated.


Question by Dean Hosking

bungalow house plans dp?

can someone pleaase help me i've been trying to sort plans for a bungalow im having built so i can work out what furniture can fit where but the plans are in 'dp'? but i dont know what this means or how do i put this into cm? ive attached the plansif anyone could help me change the measurements. thankyou so much

Question by Nik Stowe

underground electrical conduits in reactive soil

I have to provide a 160A 3P service to a building over a 65 meter run in highly reactive soil. We have been told to allow for a vertical movement in the soil of up to 300mm around the building perimeter. I am thinking of using 100mm diameter HD corrugated conduit. Will this do it or is there some other solution? I am concerned because to me 300 drop over only 65 meters seems a lot. I can allow for extra cable and loop inside the cabinet and this should protect the cable from being ripped out of its connectors but I am concerned that the conduit may tear or split.

Question by Peter Caruso

Verandah Rails

Hi everyone,

My partner and I are looking to complete our verandah with Stainless wire horizontal and a Merbau Top Rail. We are wondering what the law is now for the stainless wire fitting i.e. gap required and tension required as well as the mandatory height for handrails.


Question by Kai Tolson

Laundry in a cupboard

Are you required to have a floor waste in a Laundry in a cupboard

Question by Glenn Rees

Cancelling a project

If I cancel a Building project in Vic and cancel the Building Surveyor, how soon can I re start the project with a new Building Surveyor?

Question by Sue Dight

Treating & finishing new spotted gum decks

Recently paid a lot of money for professional to paint exterior of our 2 story home. Now a chippy is about to totally replace both top & bottom decks in wide spotted gum boards (upper deck is partially exposed to weather). Getting conflicting advice from builders -v- paintshop & painters. Builder saying don't need to use Prep / Revivor & sand - just leave finished deck for 2 weeks then coat with Intergrain Ultradeck. Paint shop says must use Prep, then Revivor prior to applying Ultradeck with light sanding in between.

Question by Jim Mckenzie


Hi my house is in the hills and my property is on an extreme slope of about 40 degrees. the slope is higher in the back, and that is where I have a problem. Along the back of the house there is a flat walkway just over a metre wide. Then there is a retaining wall that is about 1.5 metres high. I know that against the wall I should have a drain. But how do I make sure that any water that flows onto the walkway drains into the drain and not under the house? The house is a weatherboard cottage on stumps. how do I resolve the walkway to the back side of the house?

Question by Gustav Louch

Requirement to change street light bulb within commercial building

Do i need to hire a electrician to change the street light bulb (See attached picture) within commercial building assuming i have a scissor lift and a licensed operator. (or do i even need licensed ewp operator if it is within a ladder reach). Thanks for your help.

Question by HangChuen Lew

Concrete bench top moisture barrier for cupboards


when you pour a concrete bench top onsite over existing cupboards do you suggest a "moisture barrier" (black plastic) be placed under the concrete to protect the cupboards


Question by laurie purcell

Pepairing a deck between 1.0 m and 2.1m off the ground

Hello, I am thinking of replacing the treated pine deck and replacing it with merbau or spotted gum. At the same time replacing the vertical timber slats with Stainless steel wire. The height of the top hand rail is in excess of 1.00M. The distance between the posts varies from 80cm and 356cm . Can you advise the distance required between the posts if I go ahead with the stainless wire. There are 9 cypress posts in total 100 x 100mm, incl. gateThree of the posts hold up a colourbond bullnose roof 140cm wide.

Question by Jim Kennedy

Safety Glass

I have a sliding glass door (33" x 75") on the interior of my rental property that leads from the living room to a sun room. Does the glass in this door need to be laminated safety glass?

Question by Adam Van Hise

straw bale installation

Does straw bale installation meet the BCA standards

Question by Simon Verrender


Dear Madam/Sir,

I am planning to build a high school in Kenya, Mid sized, initial student population ;500, on 10 acres. Do you have any advice on where i can start or sample estimates & plans, i dont have any experience in the building sector.

Thank you,


Question by Solomon Wekhomba

laundry window

hi i was wondering is there a law where you have to have a window in a laundry?
i am about to renovate ,my laundry and the window that is in i want it removed and dont know if i need to still keep a window or by law?

Question by Callum Honey

window ventilation

we want to buy an apartment which only has glass bricks for light instead of an opening window. There is ducted airconditioning in the room but no opening window. Is this allowable? We would think this is possibly a health hazard.

Question by diana sier

Separation Walls between dwellings

Hi Guys,
I just have Qs relating to masonry wall construction between 2 units I am building.
I would like to know can I use the following?
I have been looking at BCA requirements and also was given information from the brick suppliers.
But I am still a little unclear as to understand if it is an acceptable construction...?
I would like to know if I can use the following...

Question by Baz Clarke

Aggregate size

what size of aggregate to use for residential house slab? 14 mm or 20 mm


Interior stone cladding on plywood

In my apartment, behind the TV panel, i have covered the wall (to a height of 7 ft) with marine plywood. I want to fix cladding stones on the plywood. What is the recommended adhesive to stick the cladding stones on plywood?

Question by maj dev

Rangehood requirement


I am building a house and my builder made a mistake by only leaving 200mm gap between my cooktop and sink in the kitchen, although I have made a variation (signed off) to increase the gap to 400mm.

After my inspection (rangehood, oven & sink installed), I made a complain about it and they said they are willing to the cooktop but not the rangehood & oven, with the comment below.

Question by Sylvia Hartono