Construction Industry (Housing)

Common Defects in Mass Housing have been a continuous issue that made up purchaser's impression of the value of those involved in the construction industries. The problem could be because it is a BUSINESS after all.

I have not seen a clear explanation or clarification by specific professional toward public understanding of what we are all about. Let stir a bit.

Defect

There is a misconception with the use of the word ‘defect’ by layman, site staff, purchasers, or even some architect when describing undesirable quality of architectural products. Incomplete works are not defects, they are incomplete. Improper installations of materials are not defects, they are simply wrongly done. Works that were not constructed according to Architectural drawings and specifications of the Contract are not defects, they are non-compliance.

The word ‘defect’ alone carries a few categories. There is design defect, where the design causes problem to the function, or end users. There is structural defect, which does not meet or comply with the structural specification. 

There is latent defect, which only appears after certain period of time after a particular work is completed. There is patent defect, which may be identified or observed immediately after it was constructed or installed.

Architecture Business

In current environment, a good Architect will understand that in some way, even though they are trained in Architectural Theories, and awarded with Architecture Certificate, in real world, they are not in Architecture business. They are actually in Construction business. 

One point that is necessary to be understood in Construction business is that everybody is not expert in everything, but everything has to be built expertly to become a building. In carrying out his duty, An Architect is not only required to produce good design, but also he has to administer the construction contract to ensure that the Contractor delivers the design in the most acceptable quality, construction manner, and standard.

Standard

What is an acceptable Standard ? PAM Form of Contract describes that the STANDARD in the provision of the Contract is  ’… to the acceptance of the Architect…’ Now, cynically, the clause may be interpreted as; if the Architect accepted it, then the quality is met. 

Having said that, we may have to ask; is there an interpretation of quality in Construction business involving Architecture ?. Do all Contractors share the same understanding on an acceptable Standard of all Architects who administer their contract so as not to ignorantly produce or deliver work of an unnecessarily, unacceptable quality. 

In Architecture business, the description in the PAM Form of Contract may be enough, but in Construction business, the Contractor may be counting on their non-understanding of ‘acceptable standard’ of an Architect as an excuse to most of identifiable defects works, incomplete works, improper works, and non-compliance to the contract. 

By the time the Architect’s instruction reach the site to reject a work, the rectification may require removal of a few other related or completed works.

So, let us give the Contractors an example of the description of a minimum acceptable standard which they should have met, alone, without other parties’ supervision, or cross checking , and hope that we have a good quality product.

(will be posted next)

Development Sequence

"Construction practice may vary in different places or geography, as such, these notes are just general information" . In time, new photos will be added.

 

DEVELOPMENT, TENDER, AND CONSTRUCTION SEQUENCE

Ownership

Land matters

Survey

Layout:

Submission

Layout submission carried out by Planner,

Infra:

Submission-JPP, JBA, TNB, Telekom, JKR, Masma, Road&Drainage

Submission carried out by Civil Engineer

Earthwork:

Submission

Earthwork

Submission carried out by Civil Engineer

Setting out:

Survey and setting out plan

Survey to be carried out by Chartered Surveyor, pegging shall be installed, after which Main Contractor upon taking site possession shall verify the pegging layout with their own certified surveyor. Pegs shall be protected by Main Contractor.

Planning:

Submission

Planning submission (for Building) to be carried out by Architect. Planning guidelines shall be complied.

Fire Fighting

Submission to JBPM shall be done by Architect. Bomba guideline shall be complied.

Building:

Submission

Building submission shall be done by Architect. Building guidelines/ by-laws shall be complied.

Landscape:

Submission

Landscape submission shall be done by Landscape Architect.

Tender:

Preparation of tender

Design proposal confirmed by the Client shall be prepared in working drawing sets, which will be produced as Tender drawings, Submission drawings, and Construction drawings. Tender document in parts, consist of Bill of Quantity, Preliminaries, Preamble, Condition of Tender, Instruction to Tenderer, Specifications, Schedule of Finishes, Schedule of Rates, etc.

Calling of tender

Tenderers are expected to have visited the site before submitting the quotation.

Tender clarification

Selected tenderers who return tender shall be called for tender clarification, to finalize any query before revise quotation.

Award

Selected Contractor shall be issued with Letter of Award describing the condition of the contract.

Site Possession/Commencement:

Mobilization

Upon possession of site, and acceptance of the site condition, the Main Contractor shall start mobilizing equipment, material, workers etc to the site.

Acceptance of site condition

Main Contractor shall write in their acceptance of existing site condition, mentioning that the condition of the site, the site and work access, and no obstruction to the intended works.

Submission of Performance Bond, CAR, WC shall be done by Main Contractor immediately.

Notice that site setting out peggings are protected with timber studs. The pegs shall remains protected until preparation of formwork of the affected area. The difficulties are in keeping pegs in place while the site is run by heavy machinery and excavation starts.

Verification of survey:

Setting out

Survey to be carried out by Chartered Surveyor, pegging shall be installed, after which Main Contractor upon taking site possession shall verify the pegging layout with their own certified surveyor. Pegs shall be protected by Main Contractor.

OGL

Main Contractor shall survey the original ground levels, to determine the quantity of additional or omission of earth required.

Upon possession of site, the contractor shall prepare the site on security, safety and cleanliness. Notice that the earth drain is created to discharge surface water from the site.

Coordination:

Drawings/shopdrawings

Main Contractor shall, in reference to Consultants’ construction drawings, prepare coordination drawings, covering all detail dimensions, construction method, sequence of works, etc.. Shop drawing shall be prepared by Main contractor immediately according to required timing and sequence of work.

Site

Descrepencies

Sequence of works

Test:

Soil

Pile

Concrete

Foundation:

Coordination of site before excavation

Excavation

Excavation work requires proper coordination, so as not to damage the block peggings, excavated earth not to obstruct the next works, and the retained water to be pumped out.

Piling

Piling work in progress, which design derived from soil test. Above are concrete. For the marine clay of the site, bakau piling could be specified.

As built

Formworks

Reinforced bar

Pile cap

After submission of piling point as built is accepted, the preparation of formwork and installation of reinforcing bars starts.

Concreting work for pile cap is completed.

Stump

Formwork removed, and the workers are preparing for backfilling work and installation for formwork of stump: notice the starter bars above pile caps.

Backfilling

Backfilling work completed, and the site is being prepared for installation of formwork for stumps  and ground beams.

Sample/Material

Gutter/Rwdp

Windows/glazing

Sliding doors

Roof tiles/materials

Wall/floor tile

Brick (clay/cement sand)

Sanitary piping/fitting

Cold water piping/fitting

M&E pipe/cable/trunking/ducting

Colour scheme code/board

Ironmongery/lockset

Textured concrete/imprint

Water tank

Fan hook

Main Building work:

Superstructure/ substructure

After completion of substructure works, ground beam formwork and casting are in progress.

R C frame work

BRC laying and formwork for 1st floor rc slab are in progress.

Formworks  for 1st floor columns are erected. Notice starter bars at the edge of floor slab and column, which are meant for brickwall’s rebars.

1^st floor beam and carporch beam formworks are in progress.

1^st floor column formwork in progress.

Rc framework completed up to 1^st floor and formworks are dismantled. At this point of construction, installation of architectural works /elements starts e.g.brickwall, rainwater down pipe in columns, covered M&E pipings and conduits etc. Notice that external sanitary manhole is completed, pending backfilling. Notice also orange colour upvc pipes for dicharge of rainwater ( down pipe)  have been laid pending connection to external drain and backfilling.

Underground services:

Sanitary

Cold water

TNB

Telekom

As built

Above ground rc works

Formworks

Reinforced bar

Ground beam

Ground slab

Concealled services

Ground flr column

1^st flr beam/slab

Concealled services

1^st flr column

Roof beam

Preparation for roof beam formworks. Notice that metal door frames are delivered to the site, ready for installation.

Rc framework is completed. Bricklaying and window frames installation are in progress

Brickwalls completed with aluminum window frames in place. Scaffoldings  are erected in preparation for plastering work. Notice that the rainwater down pipes are in place to receive the pipes  from gutter.

Plastering work is completing, and fabrication of roof trusses commences.

Water tank support

Architectural works

Water tank

Roof trusses

Roof covering

Wall

Windows/Frame

Upper roof covering completed. Lower roof trusses of some units are yet to be installed, pending dismantling of scaffoldings.

Glazing

Doors/Frame

Wall finishes

Wall plastering

Floor finishes

Ceiling

Painting

Painting work commences

As built

Rectification Method Statement

Works not according to Construction Dwg.

Incomplete works

Defects

Infra Works

Road & Drainage

Drain base work in progress.

Drain wall completed, notice the timber props are installed to support the drain wall against the horizontal load of the surrounding earth, until completely cured.

Pipe culvert laying in progress.

Drain cover completed.

Sewerage reticulation

Water reticulation

External Work

TNB

TNB sub station is in progress

Streetlighting

Telecom

Inspections

Consultants

Authority

During preparation and completion of painting and roof works, series of joint site inspections are carried out by consultants and developers, to identify incomplete, improper, or wrongly constructed works. Notice that timber studs used to protect setting out pegs are still remain.

Formwork for drain wall is in progress. Once road and drainage works commences, no heavy machineries should enter the unit’s parameter, so as not to damage on going work.

Painting and lower roof works are in progress. Drain wall rc work is completed pending backfilling.

TNB sub station’s fencing work is in progress.

TNB sub station is completed according to TNB’s specifications.

Preparation of formwork for gate and fencing post.

Completed Semi D units, pending completion of infra work. Notice that 1^st layer crusher run for the road is in progress.

1^st layer of crusher run, road kerb, and fire hydrant are in place.

Binding course and wearing course for road are completed. Landscape work and infra works completed, pending clearing and cleaning up for Authority inspection.

CF