Timber balustrades are built in various designs and various different timbers can be used. The most affordable hardwood of course being balau with more expensive options being Massaranduba, keuring etc. The pieces required for balustrades are most commonly found in balau as they form part of the structural pieces stocked by most timber merchants. Massaranduba, keuring etc. are largely supplied in deckboards only and are used for the actual decking with balau being used as the substructure. All three of them are equally as durable and strong and only really differ in colour and grain.
In this article we will discuss the picket style balustrade.
This type of balustrade is often the only one that completely adheres to standard building regulations as the gap between any two pieces is, or can be made, less than 100mm. It should be designed with a cross horizontal support at the top and bottom to give the pickets a support to be attached to. The bottom horizontal support is normally set about 100mm from the ground and secured to each vertical post in as long a length as possible. The top horizontal support can either be set at the top of the post and directly beneath the capping or set 100mm down from the capping to provide a gap between it and the capping. The former being my personally preferred method as it then gives the capping a more rigid support and will reduce bowing and cupping of the cap.
Each picket is then attached to these horizontal supports so that the gap between vertical pickets is equal. Care should be taken in setting the first and last one as the width of each picket needs to be taken into account when calculating the centre of each picket due to the first and last one being the vertical post itself. Pickets can be pre routed on the corners to give it a profile or left square. They can also be routed in situ resulting in the router not running all the way to the end of the picket.
A capping is then placed and secured on top of the horizontal support and posts, or just to the posts if the latter method was used. This capping can then be routed over the edges to break the sharp corner. This capping should also be secured in as long a length as possible to avoid joins wherever possible. If a join is necessary it should be joined with a 45° join directly above a vertical post. This will reduce lifting on the joint.