2.1. Species:
Shiplap cladding boards are generally sawn from naturally durable regrowth hardwoods such as Silvertop Ash, Southern Mahogany or Yellow Stringybark (ie. Class 2 durability). Other species (including Class 1 durability) may also be available on request.
NOTE: Silvertop Ash is one of the approved species for use in “high fire danger” areas by Building Control Comm. Practice Note No. 46 (Dec. 2001).
2.3. Profile:
Radial Shiplap cladding is supplied as a series of dressed 19mm thick boards with “V” shaped tongue and rebate joints (see Figure 1 above). Radially sawn Shiplap boards overlap and have an effective cover approx. 70mm, 90mm or 110mm but wider and other conventionally sawn profiles may also be available from Radial Timber Sales as a special request (NOTE: also inquire about discounted rates on “feature grade” boards).
2.4. Lengths & Availability:
Radial sawn Shiplap is generally kept in stock. Boards are supplied in random lengths of between 2.4 and 5.1m but some shorter lengths may also be included (av. lengths approx. 2.7 to 3.6m but wider profiles will contain more shorts). Short packs containing lengths between 1.8m and 2.4m are available on request. Set length boards may be available in limited quantities as a special request (a 20% surcharge is applicable to all set length orders).
3.1. Fixing Recommendations:
Setting up: Shiplap cladding is typically installed in a regular pattern with the tongues and rebates of adjacent boards fitted together (see Figure 1). Seasoned Shiplap boards will exhibit minimal shrinkage and may actually swell slightly in wetter regions or in bush settings. Noggings, fixing battens or studs should be spaced at max. 600mm centres.
Installation: If fixed horizontally, the tongues of each Shiplap board should face up to prevent water from being trapped inside joints. On long runs, boards may have to be butt joined. Alternatively, walls can be broken up into smaller panels by inserting a flashing or vertical/horizontal timber stops. Stops or mitred joints should also be used on external corners.
Fixings: Boards can be gun nailed, hand nailed or screwed with 50mm long galvanised or stainless steel fixings but care should be taken close to ends to avoid splitting. Pre-drill all holes if hand nailing and use twisted shank nails or screws into pine framing. The recommended fixing rate for 90mm or wider boards, is two nails or screws per board per stud/batten. A single screw or nail fixing is acceptable for the 70mm boards. Secret nailing through the tongues is not recommended and do not nail or fasten 2 boards together.
Seasoning & Storage: Some surface checking may occur if timber is exposed to the weather but these non structural cracks are typical in most Australian hardwoods (NOTE: unprotected west facing walls may be subject to extreme temperature changes and therefore, timber is more likely to check or move). It is also normal for hardwoods to leach red/brown extractives during heavy rain periods. Extractives tend to be less prominent in lighter species but it is advisable to cover or protect walls and paving until all extractives have leached (can vary depending on rainfall but will generally continue for up to 6 months). Packs should be stored up off the ground and under cover or protected with an additional tarp to prevent swelling. If wetting does occur, allow a min. of 24 hours for timber to dry before fixing.
3.2. Suggested Applications:
Shiplap cladding has been used as a feature on: houses, apartments, visitor centres, life saving clubs, sheds & fences.
For images of Shiplap cladding visit: www.radialtimber.com
All exposed, externally fixed cladding will tend to fade to a silver grey colour if left uncoated. The degree of greying will vary depending on the amount of exposure to sun, wind and rain. The timber used in this above ground product has natural durability and when used in conjunction with good building practices, should generally not require additional treatment against decay.
Native timbers should be offered some weather protection while acclimatising to local conditions. Radial Timber recommends the application of an oil based sealer or decking finish on external timber (especially if unseasoned or fixed during extreme weather conditions). There are a variety of treatments, stains and coatings available and most can be applied prior to or shortly after fixing. For more detailed information, please refer to Radial Timber “Finishing Recommendations” at: www.radialtimber.com
|
