Why Use TrussVision?
vc_separator no-text align_left wpb_content_element vc_el_width_5075pxstyle="border-style:;border-color:#fc5f16;border-width: 4px;"12#fc5f16Residential buildings.
The Law.
Owners of residential buildings must be aware of their responsibilities.
Substitution of Regulation A19
Regulation A19 of the Regulations is substituted with the following Regulation:
70 Substitute Regulation A19 with the following: A1 9 – APPOINTMENT OF PERSONS RESPONSIBLE FOR DESIGN, INSPECTION AND ASSESSMENT DUTIES
(1) Where in terms of these regulations and in respect of the erection of any building: (a) a Rational Design or rational assessment, is required in terms of : (i) Regulations ZA(l)(b)(ii), A(1)(3), A23(4), G1(3), 04, P2(2), q3), R(3), Tl(2) or W4 in respect of a system, measure, facility, parameter, or installation, as relevant, or (ii) a part of SANS 10400; or
(b)a geotechnical investigation is required in terms of Regulation F3 the owner of the building shall subject to the provisions of sub-regulations (4) and (5) appoint and retain one or more approved competent persons to undertake responsibility for the work associated with such regulations including any inspections and certifications that may be required.
56 No. 31084 GOVERNMENT GAZETTE, 30 MAY 2008
Commercial Buildings.
Owners are reminded of the requirements of Regulation 9(4) of the Construction Regulations 2014, (emanating from The Occupational Health & Safety Act No 85 of 1993 which requires that any structure be inspected regularly to ensure that the structure is safe for continued use.
Section 11(2) states:
“An owner of a structure must ensure that:
- a) Inspection of that structure is carried out periodically by competent persons in order to render the structure safe for continued use;
- b) That the Roof inspections contemplated in a) above are carried out at least once every six months for the first two years, and thereafter annually;
- c) The Roof structure is maintained in such a manner that it remains safe for continued use;
- d) The records of inspections and maintenance are kept and made available on request to an inspector”
Even though legal claims pertaining to this depends very much on evidence to prove negligence and might be hard to prove, owners of commercial property are urged comply to this regulation to ensure safe working environments and avoid any possible claims. The roofs that are most commonly susceptible to structural failure have been found to be large span (over 10m) timber Roofs with concrete roof tiles. The good news is that this reduces the risk for most residential roofs, but on the other hand includes most commercial buildings.
Roof structures that have survived for 20 years offers no grantee of future structural integrate!
The Insurance Dilemma
Home owners are often unaware of their Insurance obligations and for this purpose, I have included an important extract that was presented to me by an insurance broker recently:
KNOWING WHEN TO COMPLY.
Agreements like short term insurance policies contains General Exceptions Conditions and Provisions requiring the parties to comply to these terms and conditions with consequences attached to non-compliances. Your attention is drawn to the following general Exception Condition and Provision.
GENERAL EXCEPTION, CONDITION AND PROVISION.
Defective Design, Lack of Maintenance and Cost of Maintenance
Policies do not cover loss of or damage caused by or attributed to defective design, defective workmanship, defective construction or defective material or lack of maintenance and the cost of maintenance to the insured property.
GENERAL CONDITIONS: Prevention of Loss
The insured shall take all reasonable steps and precautions to prevent accidents or losses. In the event of a claim and it is identified that the root cause of the claim results from non-compliance, the claim will be rejected.
Why are roof structure inspections necessary?
It is a statutory requirement to comply with all the provisions of both the Building Standards Act Section 14(2A) and the National Building Regulations (Regulation A19) in order to obtain an Occupation Certificate from the Local Authority.
Through the proliferation of bad practices in the Roof Erecting Industry over many years, we have now witnessed an increase in this disturbing trend of Roof Structure failures.
Case studies, worldwide have confirmed that a lack of compliance with recommended installation procedures were the common cause of most of these failures and collapses.
We know that roof structures are made up of individual wood framing members that are connected with specially designed metal plates. These are amazingly strong once they are installed & braced as a system, but, they are surprisingly fragile as individual trusses. They have very little lateral strength or resistance to lateral forces.
The successful Erection of Timber Structures is possible through compliance with the National Building Regulations Requirements as contained in the SANS 102453 & SANS 10400(L) codes of Practice.
The role of the Inspector is therefor to check that these guidelines are carefully followed.
Pre-fabricated trusses that are handled with care, erected and installed properly, have proven their value in the industry. Unfortunately, their value is sometimes questioned when failure or collapse occur.
It is a fact that many roof structures fail during the construction phase while others take years for an incident to occur.
Incorrect loading or overloading during construction, like high winds or mishandling of trusses during erection, utilizing weak members or bad joint connections, damaged, broken or improperly repaired trusses, or installing unacceptable or unauthorized design changes on site.
These are some of the main reasons why trusses fail or collapse.
Then there is the problem of 3rd party interference after these structures were erected.
These mainly involve adding additional services like air conditioning systems, water system and electrical systems to the structures, which they were not designed for.
There is an International Residential Code of 2006 that states: “Truss members shall not be cut, notched, drilled, spliced or otherwise altered in any way without the approval of a registered Professional Engineer”.
How often have we seen these “remedies” done without any consultation, at the Erectors own discretion?
Structures with proper design and construction of bracing systems are essential in reducing and / or eliminating timber structure failures.
As I have mentioned before, the fate of these structures are to a large extent, determined right at the beginning stages of construction/erection.