W Stevenson and Sons Ltd recently launched DryBlock, a system designed to enhance the weathertightness of masonry buildings.
Applied in the context of best design practice, the system results in water- repellent walls. This, according to product manager Shaun Owen, offers “an excellent second line of defence against water ingress should the first line of defence, such as sealer, plaster or paint fail”.
“It also facilitates the use of architectural masonry in applications where it would never have been considered previously.”
Mr Owen says DryBlock technology has been appraised by the Building Element Assessment Laboratory’s (BEAL) 14-day leak-test. Having proven all its product characteristic claims to be true, the DryBlock System is now a safe and efficient building system in terms of the New Zealand Building Code.
“We consider this to be a breakthrough in masonry technology. Feedback from our customers, including builders and home owners, supports our view that DryBlock should be the consumer’s first choice for withstanding New Zealand’s wet, cold and humid environment in sustainable manner,” he says.
For the DryBlock system to be fully effective, it is essential that good practice be followed right from the design process through to the completed installation.
DryBlock masonry blocks must be used with DryMortar and all other components of the DryBlock system.
The “panel concept” must always be obeyed to control cracking, with block work being designed in panels, tied together with suitable steel and separated by control joints .
The engineer must pre-empt crack control through well-placed control joints and the use of suitable crack control steel, including in-joint reinforcing if required.
This must be supported by generous top protection, such as eaves and suitable coatings. But, in the end, Mr Owen says, no building system, however good, will succeed if not supported by good detailing and good workmanship.
“Best practice makes the difference. We also like to work closely with designers, builders and blocklayers to ensure optimum application of the system in accordance with DryBlock specifications.”
The product is available as a veneer or a structural block in fair face, honed face and split face finishes in eight colours. It is also designed to take surface treatments such as paint, plaster, clear sealer or a cladding.
The system offers designers, builders and home owners several advantages. It is recommended in all single-skin masonry walls and in some veneer applications.
“This advance in masonry technology ensures water repellency becomes an integral part of the wall. It reduces colour issues such as staining and efflorescence in architectural masonry.
“The builder doesn’t have to wait long for blocks to dry out during wet weather construction, and they also don’t have to wait long for blocks to dry out before lining. In certain situations you can begin lining the interior prior to completion of the exterior weathertight coating.
“The builder can directly fix interior plaster board, which raises the question of the need for DPCs between timber and DryBlock.
“In fact, DryBlock technology offers all the advantages of building with typical masonry, including structural strength, durability, fire-control, noise-control and thermal mass performance, while offering value-added built-in water repellency.”
Call 0800 DryBlock (0800 379 2565) for further information.