Comparing Apples with Apples
Getting the most from you contractor
When selecting a solid plasterer it is important to understand some aspects to determine the best price and outcome for your job.
It is likely that you will get more than one quote so it is important to have a better understanding of the scope of works for your particular job and what best suits your needs.
Did you know that most people assume that each solid plasterer contractor has the same work procedure? This assumption is probably the most common reason some finished work results in problems for the client.
Following is a brief outline of terms that maybe included in our detailed quotes for your rendering work.
Masking:
This would have to be one of the most loosely termed words used in scope of works. Correct masking contributes to the overall finished appearance of the work.
Masked finished floors such as tiled areas, timber decks, driveways etc should be covered in quality materials. Render in general contains large amounts of water that breaks down materials such as paper masking tape and soak through canvas drop sheets thereby permanently stains and damages these areas.
Windows need particular attention. Glass is a porous material and render can easily leave permanent scratches as it is removed. If fly screens and window glass are exposed to render, damage may occur during the cleaning process. Tape that is left to bake on by contractors is commonly removed with a paint scraper and turpentine. The masking material should be held down with quality long life tape that can be removed after several days. CJA Solid Plastering Pty Ltd uses a quality plastic film to cover the entire opening in conjunction with long life tape.
Control or Expansion Joints
Control joints, also known as expansion joints are necessary in areas that are prone to movement. The movement may not be obvious in the existing brickwork but can be as little as hairline cracks. It is the contractor’s responsibility to make this movement obvious to the client.
Render is hard and cement based and has little or no flexibility. A fraction of a millimeter of movement can cause an unsightly crack and often results in drummy render which can cause delaminating. These areas are sometimes highlighted in existing brickwork by mortar joins that run vertically as opposed to the usual step in the mortar joins that are common in most walls. Control joins are necessary above windows as these areas create a weak point in the structure and are more prone to cracking.
The management of control joints plays an important part in the prevention of render cracking and it is important for the contractor to be familiar with correct procedure for expansion and contraction.
Skim or Screeded Finish?
This is a choice that is not often given to the client but can play an important part in the overall street appeal of your home.
Skim – or skim-coat is a term used to describe the application process of the modern day pre bagged renderers. It is a quicker way of applying the minimum two coats of render required to meet manufacturer’s specifications. Although this is a thinner coat than a screeded finish, it is probably the most common procedure carried out by modern applicators. It is a cost effective method and is most suited to those areas that are not susceptible to sidelight conditions such as an area when the sun is vertically over a wall or when using modern exterior lighting which create a shadow in every hollow.
Areas that suit this finish are small walls (under 2 metres high) or areas without exterior lighting or have good overhead cover such as eaves.
Screeded -This process is similar to skimmed work and is a process that is derived from traditional (mix your own) site render. The main difference between skimming and screeding is the use of a screed such as an aluminium straight edge used after the trowelling and before the floating process. This technique is continued until the wall is flat over a span of 2 metres with as little as 1mm tolerance under the screed.
Screeding is suitable for walls that are susceptible to sidelight conditions such as high walls in excess of 2 metres, fences and walls that are likely to have exterior lighting washing over the wall.