New AS1684
There was a new AS1684 - 2010 (Timber Framing) referenced by the BCA 2011. This has meant some changes to some timber sizes which the timber yards are on top of. One of the small interesting changes was a note added to Table 9.21 (page 202) detailing the use of plywood bracing for tie down which states "not applicable for tie-down at sides of openings". This means for all our jobs except N2 tile roof (tie down is nominal) we must 'add' tie down beside openings.
Signs to water tank taps.
There is a difference between the requirements for signs on the taps from water tanks between the Qld Development Code and Plumbing Code. The State Government has verbally advised either one is OK. My view is this is water supply and controlled by the Council Plumbing Inspectors.
New Products
There are always new products on the market with the salesman promising it will solve all of our problems and it may but be careful you look at the paperwork or send it through to us to look at it to make sure we can justify the compliance before you go to far down the track.
Follow the plans
We and your admin staff work very hard to make sure the approvals a correct. Make sure the site personal follow the plans or ask the question before going away from the plans.
Brace sheet tie down
A bit more info on bracing tie down. A brace sheet rated at 6.4kn/m requires a 13kn tie down each end and at 1200mm centres. This is a bolt or screw that will with stand a pull out strength of about 13 tons. If your tie down system is say 8kn this is a 29% reduction and now your 900mm ply brace is worth 3.50kn with a loss of 2.26kn each brace. When you are selecting a tie down system check the pull out strength, edge distance and depth will suit the purpose. Example: it is no good using a 150mm screw in bolt mid-slab if the slab thickness is 100mm.
Quiet times
We are using this quiet time to:
Go through our old un-finalised approvals and sending letters to owners giving them 3 months to achieve a building final or the application will lapse and be sent to Council to deal with.
Scanning all of our paperwork so it is easily accessible anytime you have a question and looking at our systems and developing specific checklists that will help the applications go through more quickly.
If you are experiencing slow approvals or finals and are not sure of what the hold up is please contact me as this should not be happening. I understand its cash flow that keeps us all in business specially due these quiet times.
Sound Ratings
The sound rating between units such as duplexes and townhouses is very high compared to 2 years ago. When you choose your separating wall system no only do you have to achieve a one hour fire rating (60/60/60 FRL) but also the sound requirements such as between habitable rooms is 50 Rw+Ctr (Ctr is a negative number) and discontinuous construction (cavity). In many cases a plain 200mm block wall will not comply with the sound rating requirements.
Acoustic Requirements
If you are engaging an acoustic engineer make sure they will certify their report so that it complies with the requirements of Qld Development Code MP4.4 schedule 3. This is a list of information the acoustic report must address.
Structural Software Protocol
Because there are products appearing on the market that can be used by anyone and as they did for the energy rating software the Federal Government is proposing a protocol standard that software developers must meet when designing structural design software. This will mean in the future, training and accreditation will apply to the users of this software.
Cyclone Yasi
In late April James Cook Uni released a report into structural damage to buildings and found that less than 3% of all post-80s houses experienced significant roof damage and 12% (up to 20% in some towns) of all pre-80s had significant roof damage. We must be doing something right since Cyclone Tracy. The study did reinforce the need to design the whole building including the cladding, doors, windows, roller doors, eaves lining and skylights to resist the expected ultimate limit states wind forces. This was also one of the findings from the wind storm that went through the Gap in Brisbane.
That's all I have and not one mention about retaining walls..........
