Monthly Archives: April 2016

Construction blunder

BCA’s have a responsibility under the Building Act 2004 to check that “an application for building consent complies with the code.” They must not issue a building consent unless they are satisfied on reasonable grounds that if the Plans and specifications are followed, the building will be code compliant. It’s fairly simple description of the responsibilities and the duty of the BCA.
The type of buildings are categorised into Residential 1: 2: 3 and Commercial 1: 2: and 3. The people performing the duties are supposed to be allotted a certain competency level depending on their level of knowledge. This means that is a certain area of a building is an alternative solution for, and the person is only assessed acceptable solution competent, the checker needs to have the consent looked at by a more qualified person. Simple in theory but in practise, BCOs working above their competency or BCO actually competent for what they are assigned is not investigated.
Tauranga City Council recently had a consent which showed a roof coming out of the upper wall. At the lowest point, the intersection with the gutter is shown in FIG 8B of E2/AS1. The parallel apron flashing is shown in FIG 48. The upper end of the roof penetration is still within the wall, and the flashing requirements of the upper termination is not an acceptable solution detail. This does not mean it is overly risky, just the policy people in the former BIA and DBH did not recognise the particular detail would become popular among the risk taking designers.
To close off the cavity to prevent any wind driven moisture from the entering the cavity the apron flashing must have a stopend at the high point and sealed to the cladding on the outside, This stops moisture flowing down the wall or from wind driven sources from entering the cavity. This detail has been approved by mot BCAs presented to it because the moisture is prevented from entering the cavity in quantities which would cause mould, nuisance or rot.
The BCO rejected the detail and the explanation which showed the moisture being prevented. He made the designer flashing 200mm either side of the junction from the uppermost roof point (600mm above the junction) to the floor slab. The barge flashing along the high part extends into the cladding penetration, introducing a capillary action moisture point so the detail the BCO accepted needs to be flashed more strongly because of the introduced capillary moisture ingress.
Clearly the BCO does not understand the movement of moisture, the simplest method to prevent ingress nor the building code and as such should not be making decisions which are far above his head. He is what I would describe a monkey checker. As long as what is shown him is the same as the picture in the acceptable solutions, he ticks the box. If a detail is different he does not have the knowledge t0 assess it and make a decision. Because he cannot make a decision, he needs to ask a question, but he does not know what to ask for. He does not discuss it with anyone else, but asks a secret squirrel type question (The wall to roof flashing detail does not clearly show compliance with E2. The relationship between the wall internal corner flashing (below the soffit) and the roof wall flashing is not clear. Please revise?) The question is accompanied by a screen dump of the gutter end of the junction, which is addressed in Fig 8B.
The designer is left scratching his head, and the expert he asks for assistance also has no idea. He addressed the entire roof wall intersection from the accepted alternative solution detail at the high point to the E2/AS1 details. He finishes by pointing out the wall junction is below and isolated from the roof wall and there is no relationship between the two. But this was rejected (obviously the BCO thinks he is more knowledgeable than the expert) and the designer was “guided” to produce the completely over the top detail.
Will the designer complain about the process? No. he has already done it and is now being punished by bullying checking. The level of detail he is required to produce is 10 times the detail Jennian or GJ Gardner are asked for comparable homes.
Does the home owner? No. He wants the consent as quickly as possible.
Does Ministry of Building Innovation and Employment have a procedure for assessing complaints about BCAs? Yes and no. The Ministry will only assess a complaint after you have exhausted the Councils complaint procedure , searched the determinations to see if there are any comparable decisions already made, found the complaint form on the Ministry of Building Innovation and Employment website and filled it in in its entirety and been accepted by the Determinations department. It is too convoluted to be effective.
This is one of the ways the role of Councils increase the costs of construction and it is common place in the New Zealand. The Council produced rebuttal against the claim Councils increase costs did not look at anything other than fee and charges. Delays, fees, unnecessary construction all were ignored.
The Council need to have the BCA removed from them. If they wish to provide the service then it will be in competition with other providers. This will see the 150 per hour charge for unqualified and inexperienced BCO lowered drastically. CPEngs are able to be engaged for less. The actual building consent process and inspection need to be opened up to competition for the sector to realise the level of efficiency that will bring benefits.