We strongly recommend that the installation of our cladding products is undertaken by Qualified Professionals.
membranes
- To be used on all rainscreen cladding.
- UV Facade membrane to be used on open jointed cladding.
- Normal BBA approved breathable membrane to be used on closed rainscreen cladding.
insect mesh
- Install Insect mesh around all open cavities.
timber cladding support battens
- All battens to be treated to UC3, all cut ends to be treated on site.
- Vertical cladding to be supported with 45mm x 45mm treated battens with a minimum 15 degree slope.
- Horizontal battens to be minimum 38mm x 50mm.
- Recommended spacing of battens should be 450mm centres and not exceed 600mm centres.
- Ensure sufficient space behind the cladding for ventilation and drainage.
fixings
- Stainless steel fixings type 304, or 316 near coastal areas.
- All nails to be annular ring shanks, minimum 50mm for 16mm-20mm thick board, or the nail length to achieve a point side penetration of 2½ times the thickness of the cladding board into the batten.
- Minimum 2 face fixings required for boards up to 150mm wide and additional fixings for wider sections. We recommend maximum board widths of 150mm to reduce overall shrinkage or swelling.
- Fix nails or screws approx. 20mm from the end and edge, avoiding splitting of the boards. Some timbers require pre-drilling,
- Do not secret fix through the tongue or groove.
- All fixings to lay flush with the surface of the cladding.
- Fix the cladding, ideally, at 450mm maximum centres.
board configuration and layout
- For horizontal rainscreen the grooves need to be at the bottom to minimise the collection of water or pollutants. So install tongue up.
- Vertical claddings need to be chamfered at the ends for drainage into the cavity.
- Minimum 2mm gaps should be left around the boards for expansion, larger gaps to be left for differential movement, especially in timber frame constructions.
- Allow between 6mm to 10mm for drainage gaps on corner profiles, ends, sides or other materials (check the compatibility of the cladding with other materials in the construction, to avoid/minimise corrosion and staining).
- Ensure all edges and sides are sealed
- Cladding to be installed at least 250mm above ground level.
- Store cladding away from direct sunlight, rain etc prior to installation or during acclimatising to minimise the risk of splitting, checking or distortion.
- Most prefinished cladding requires timber to be dry, ideally kiln dry below 18% and the profile needs to have eased edges *
* Always refer to the finish/coating manufacturer’s specific guidelines before proceeding
with coating/treating/finishing and approval of detail etc.
factory finished/coated claddings
- Always keep separating membranes between the layers during handling and transit to protect damage to the lacquer and sticking to surfaces.
- It is important to follow applied product manufactures guidelines due to the large variety of finishes, coatings and treatments available.
- Ensure all edges and sides are sealed prior to installation, including any fixing holes.
- All factory finished products need minimum annual maintenance i.e. to clean surfaces any pollutants moreover touch up for any degradation.
general maintenance comments
Timber will weather, oxidise and is susceptible to fungal/ mould staining if unprotected or un-treated, changing the aesthetics of the timber. During the early weathering process the timber surface may also show signs of variations in colour, which should gradually even out, this depends on exposure. Colour variation in wood is an inherent characteristic of wood i.e. between and within board variation of colour should be expected in wood. We provide a sample service upon request to help in the selection of cladding species.
Annual maintenance is recommended; i.e. basic care and maintenance for uncoated or untreated wood, depending on the type of pollution present, would be to wash off with water (do not flood), or sand it off. Bleaching can also be used to help remove stains.
Resin exudation can occur in both finished and unfinished cladding and is not considered a defect. Resin needs stop flowing and allowed to harden before removing it e.g. brushing off and final stains cleaned with methyl spirits- over coating is required immediately for finished/painted cladding surfaces.
Surface checks and splits will occur in timber and the extent of these will vary from specie and exposure of the cladding as soon these are detected these need to be improved as quickly as possible in order to prevent further development. The above are general guidelines but cover some of the key aspects, as every project needs to be considered individually.
