Welcome To


Quantity Surveyors

Professional Quantity Surveying

Professional Construction Quantity Surveying

Project Management and Principal Agency



During the start of the millennium in 2000, the Practice, Oosthuizen and Associates Professional Quantity Surveyors was established.
The Practice obtained it’s first and extremely interesting project in Dullstroom Mpumalanga being a Trout and Country Estate, “Dunkeld Country and Trout Estate”.
The appointment was for Project management and full Quantity Surveying services of the overall phased Development as well as the Construction management thereof.  The scope comprised English style boutique hotel, double level cabins, multitude of trout dams, restaurant/kitchen/dining facility, conference facility/chapel and complete infrastructure of civil and electrical services.  The value in 2000 was approximately R 4 million (Currently would be around R 40 million).
Since, this estate became internationally well know and of the most successful estates in Mpumalanga. For further detail please visit www.dunkeldestate.co.za.
Since 2001, the Practice was mandated for extensive Quantity Surveying and Principal Agency services for a Development Company in Somerset West and completed various successful Residential Developments in the Western Cape area.
During the “recession period of 2008”, work become scarce and the Practice was pro-active to diversify in providing additional Professional services and assistance for smaller and large Construction Companies in the Construction sector in a successful attempt to bridge the “low” stage in the industry.

These additional services rendered included but was not limited to contractual advice, mitigation and resolutions, assistance with structuring building construction and quantity surveying departments for more efficiency, tendering, construction management, etc.
The Construction Company, CSV Construction (Pty) Ltd utilised most of the services and time in establishing and heading their Quantity Surveying, Tendering and Building Construction section. Extensive services were also provided for their newly established construction and development company in Namibia.
Being involved with this alternative sector, experience in addition to the Professional Quantity Surveying sector, was gained in Construction, Project Management and Contractual claims and resolutions.
From the structuring of the contractor’s quantity surveying section, the Practice commenced with the establishment of a mentorship system/program (in coordination with the SACQSP registration conditions) which enabled CSV’s willing construction quantity surveyors the opportunity to also register as Candidate Quantity Surveyors under the Practice’s Professional Registration and which became an integral additional service which was rendered. The mentorship program then, was still in its early days.
However, the decision was to expand this during the years to come as an additional service to the industry and enable Construction Quantity Surveyors (and those from other sectors) whom may not have been able to Register as a Professional Quantity Surveyor, the opportunity to follow a full structured mentorship programme and eventually register Professionally with the SACQSP.

The Mentorship programme is in process with three registered candidate quantity surveyors enrolled (two from CSV Construction) which the Practice is assisting on their road to Professional Registration with the SACQSP and whom passed their first exams above average.  The mentorship program is currently being formally structured and will soon be available to more of these candidates. Costs by Contractors or others towards this program may also be utilised in their BBBEE structure.
Notwithstanding the above, since March 2018, the Practice’s principal focus is dominantly to regaining access to the professional Quantity Surveying service market with in addition, the extension of the mentorship program.
The Practice comprise Leonard Oosthuizen as the Principal Registered Quantity Surveyor and Johan Dawid (Dawie) Wiehman as a Candidate Quantity Surveyor as well as a secretary.
The Practice have entered firm relationships and informal associations with other selected reliable freelance Quantity Surveyors and established Practices for assistance in the event of excessive work load, thus lowering overheads and still enabling provision of effective services on any large project.
Notwithstanding the size of the Practice, decades of accumulated experience and knowledge of the Profession, development, construction Industry, substantial resolutions of contractual conundrums, internal effective structuring, etc. differentiate this Practice to others with an edge to risk mitigation and value engineering as being a productive multiple skills Practice ensuring minimum risk Professional services, advice and cost effective projects.

BBBEE status

Application for BBBEE status as an EME under section of Built Environment Professional (BEP), Practice is in process and should be completed in due course which will provide us with an estimated BBBEE level 4 or 5.   



With reference to the above, the Practice relates to a vast base of historical knowledge and experience in the Consulting as well as the Construction sector which provides vision of project viability and risk assessments as early as the inception stage of a project.

We are also well acquainted with alternative successful solutions of construction and/or re-instatement of projects such as Turnkey package, Multiple Procurement-Project management, Cost Plus, Negotiated, Turnkey with provision of financing options and combinations hereof for either time or cost saving to the Client, or both dependent on the scope and type of project. 





  • Concept advice on project-property combination

  • Initial advice on cost of property-viability

  • Initial advice on rentals/sales-viability

  • Concept, elemental and bill estimating

  • Consultants professional fees evaluation

  • Viabilities and analyses

  • Project cost advice

  • Project budget/s and control

  • Cost and procedure negotiations

  • Tenant negotiations

  • Tender documentation

  • Tendering procurement

  • Tender reporting and adjudication

  • Contractual mitigation and resolutions

  • Contractual management

  • Construction cost control

  • Cost planning and advice

  • Design value engineering

  • Life cycle costing

  • Principal Agency

  • Negotiations

  • Valuations and replacement costs

  • Risk analysis

  • Advice on and use of CIDB contracts and sub-contracts

  • Tenant representation

  • Value management


  • Assist in understanding the SACQSP conditions of the professional registration process

  • SACQSP requirements and educational levels of enrollment

  • Facilitating enrollment with SACQSP

  • Mentor-ship of interim process until preparation of final project report and APC verbal examination and Professional Registration

  • Internal and external individual and group mentorship programs for Construction and other QS’s (SACQSP conditions)

  • Logbook and other documentation

  • SACQSP modules assistance


  • Contractual guidance and recommendations

  • Contractual mitigation and resolutions

  • Contractual notifications and claims formulation

  • Contractual claims adjudication

  • Representation

  • Assistance with adjudication, mediation, arbitration

  • Expert witness


  • Project/Building tender pricing services or assistance

  • Tender documentation completion and submission

  • Formulate and manage turnkey projects

  • Contractor’s representative

  • Dealing with contractual matters

  • Construction management and procedure

  • Programming and critical path analyses

  • Construction documentation

  • Contractual notifications and claims

  • Final accounts completion and negotiations

  • Mentorship program of Construction Quantity Surveyors for registration as Professional Quantity Surveyors


  • Life cycle costing

  • Landlord representation

  • Tenant acquisition and allocation

  • Tenant installation cost calculation

  • LTV calculations

  • Marketing and sales management

  • Property finance assistance

  • Maintenance cycle costing property

  • Repairs costing tenant damages

  • Levies calculations

  • Body Corporate and HOA representatio

  • Lease Agreements

  • Deeds of Sale

  • Lease renewals or terminations

  • Portfolio management

  • Property inspections



Knowledge and experience generously shared, reveals multiple opportunity and success

Sincere appreciation for your valuable time in scrutinizing our introduction. Trust this will further a professional relationship for current and future possibilities.



Below we've listed projects that we have been involved with. Some we were involved with as consultants and others we were in charge of construction.

Please click on the images below to view more details on each projects





Leonard J Oosthuizen
Principal Registered Quantity Surveyor
Leonard Oosthuizen commenced with the degree in BSc Construction management in 1984 for initial three years of study and changed curriculum to graduate in 1988 from the University of Port Elizabeth (UPE), currently the Nelson Mandela Metropolitan University (NMMU) and received the degree in BSc Quantity Surveying.

He worked part time at the Cape Town based Construction company, Multi-Bou Cape, from whom a full bursary was granted while studying Construction Management until 1986. Valuable experience in construction management and detail was gained during his vacation work at this firm. Thereafter, he worked as a registered Student Quantity Surveyor at Thompson & Thompson Quantity Surveyors in George until graduation.
After SADF National Officer’s training in 1990, he commenced work at F Jordaan Registered Quantity Surveyors in Windhoek, Namibia as a Junior Quantity Surveyor in Training. Soon thereafter he joined Philip Main Quantity Surveyors in 1993 where he registered with the Namibia Council for Architects and Quantity Surveyors as well as the South African Council for the Quantity Surveying Profession and become a partner at a young age in the firm until he left due to family reasons for South Africa in December 1999.

In addition to experience in various Quantity Surveying services in building and civil construction, extensive experience was gained in the contractual element of the profession such as claims adjudication, dispute resolution through mediation and arbitration and completed various related courses and workshops. He became well acquainted with the country whilst extensive travelling as Project Quantity Surveyor in literally all wind directions visiting various urban and remote rural areas outside Windhoek.

Further, he established a development company during his time in Namibia and successfully developed several residential developments. Experience in Project and Construction Management as well as Tendering in this sector was gained.
He accepted Namibian Citizen (due to marriage) during his stay in Namibia and currently legally holds dual Namibian/South African citizenship enabling ease of traveling and services on both sides of the border in accordance with the Namibian council guidelines and conditions.

In South Africa he started his own Quantity Surveying Practice, Oosthuizen and Associates Quantity Surveyors (O&A Quantity Surveyors)
The combination of the vast scope of experience and skills gained, equipped him at an early stage to venture various interesting boundaries of the Profession and the Construction industry while continuously gaining and accumulating further valuable experience and skills.

His experienced in various fields and sectors of the built environment ensures any Employer to receive personalized service, tailored specific as required by the Employer and/or the Project needs.

Johan D Wiehman
Registered Candidate Quantity Surveyor
Dawie Wiehman studied at the College of Cape Town and in 2007 qualified himself in N6 National Diploma in Building as well as a DOP – Draughtsman. Due to his ten years of experience and continuous mentorship under Leonard Oosthuizen, he was allowed by the SACQSP to register as a candidate quantity surveyor during 2018. With the Practice’s mentorship program under which Dawie is registered, he will be registering as a Professional Quantity Surveyor in the following years to come.

In 2008 Dawie commenced employment for a construction company as an assistant site agent and obtained practical experience in initial construction quantity surveying services as well as in building and civil construction.

In 2009 Dawie was employed by CSV Construction and worked under the mentorship of Leonard Oosthuizen of O&A Quantity Surveyors where he obtained extensive personal experience in construction quantity surveying, contractual issues such as notifications, claims, sub-contractor claims adjudication, etc.

He also managed a section of the tendering department of CSV and acquainted himself with all facets of the costing, tender procurement and submission documentation and process of all different types of tenders such as bills of quantities, lump sum, schedule of rates, turn key projects, etc.

Dawie was located in Namibia for two years where he Project managed and was the Contractor’s site project quantity surveyor on a R 110million UNAM 1152 bed student accommodation project which included the initial estimating, viabilities and substantial value engineering which eventually changed the non-workable project from R 4000/bed to a realistic budget affordable by the market of R 2200/bed and thus a viable project, which today is filled with students and being the first of its kind.

During this time, he also obtained valued experience in consulting quantity surveying services from the Practice which eventually allowed him to register with the SACQSP.
He became well acquainted with the country during his location in Namibia.

Dawie Wiehman is currently with the firm and undergo continuous mentoring under the Firm’s program. He is more than capable in all the above aspects and since 2009 proved himself experienced and extremely valuable within the Practice, Construction sector and the Quantity Surveying Profession.




Mon-Fri 8am – 5pm


Leonard: +27 82 871 7456
Dawie: +27 78 500 3117


31 Topaz Street
Somerset West