Cedar weatherboards and timber

Refer to the PDF flowchart for a visual of the steps below:

1. If unpainted and weathered:

• Treat moss and mould with Resene Moss & Mould Killer (D80).
• Thoroughly scrub with Resene Timber and Deck Wash (D813) with a short hard-bristled scrubbing brush.
• Use Resene TimberLock (D48) to condition weathered Cedar before painting as it can be difficult to sand.
• Ensure the surface is clean, dry and dust free.

If new:

• Ensure the surface is clean, dry and dust free.

2. Prime using Resene Wood Primer (D40).

3. Topcoat:

• 2 coats of Resene Hi-Glo (D31) or Resene Hi-Glo CoolColour (D31C) gloss.
• 2 coats of Resene Sonyx 101 (D30) or Resene Sonyx 101 CoolColour (D30C) semi-gloss.
• 2 coats of Resene Lumbersider Low Sheen (D34) or Resene Lumbersider Low Sheen CoolColour (D34C).
• 2 coats of Resene Lumbersider Matt (D327) or Resene Lumbersider Matt CoolColour (D327C).
• Look for the cc next to the colour name on colour charts for CoolColour options.

Notes:

• Cedar is a durable timber and may be left to weather uncoated. However it contains water soluble tannins which will bleed through waterborne primers and paints including Resene Quick Dry (D45) (see photo above). Prime with Resene Wood Primer.

• Stains from the Resene Woodsman range are not affected by the resin bleed and may be applied directly onto Cedar.

• Conditioning with Resene TimberLock, while a good idea before priming, will not prevent the tannins leaching through Resene Quick Dry primer.

• Avoid painting or coating surface forming wood stains unless stripped. The top layer of cedar degrades quickly under U.V. attack resulting in the stain flaking off. Contact the Resene advice team or ask staff at your local Resene ColorShop if you need to re-stain or paint Cedar that has an existing flaking stain.

• Redwood is part of the same family as Cedar and while it is much less common for new or recently constructed homes it presents the same issues when painted.

• Despite being officially classed as a ‘hardwood timber’, cedar is a comparatively soft timber (more so than pine) and is easily damaged. Do not water blast. Instead, wash and scrub with Resene Timber and Deck Wash.

• Aged grey Cedar may be painted. Apply 1 coat of Resene TimberLock first to condition the Cedar before priming and painting. Typically, cedar weatherboards are not smooth sawn and are difficult to sand and prepare. Resene TimberLock may be used as an alternative to sanding where the surface or texture of the timber makes sanding impractical.

• Cedar is easily painted and is an excellent substrate for paint (more so than pine for example). Once painted, repainting is easy. Spot prime bare areas with Resene Wood Primer rather than Resene Quick Dry.

• Resene Sonyx 101, Resene Lumbersider Low Sheen or Resene Lumbersider Matt suit cedar more than high gloss Resene Hi-Glo due to the surface texture of the timber, particularly quarter sawn boards. If repainting refer to flowcharts 2 and 3 and prime or spot prime with Resene Wood Primer as needed.

• Consider using a Resene CoolColour to minimise heat retention if selecting a dark colour. Resene CoolColours have also demonstrated improved durability over standard formulations.

Key accessories

• Resene Moss & Mould Killer
• Resene Timber and Deck Wash
• A good quality brush:
  • 75-83mm PAL Legend brush or Basil Hybrid for confident DIYers or those with larger hands
  • 63-75mm PAL Legend brush or Basil Hybrid for those new to DIY or if you have smaller hands
• Contract filler for any cracks or nail heads
• 100-120 grit sandpaper for preparing and 180-220 grit sandpaper for sanding fillers etc
• Paint pot to decant into if using 10 litre pails

Add ons

• Drop cloths
• Resene Hot Weather Additive for hot dry conditions
• Painter’s dusting brush
• Turps for Resene Wood Primer/Resene TimberLock
• Painter’s gloves (good for both sanding and painting)
• Resene MoulDefender for extra protection against mould

If applying in cooler conditions (under 10 degrees), add Resene Wintergrade Additive to Resene Summit Roof (D315S) to enable it to dry down to three degrees. Or if light rain showers are predicted, consider using Resene Umbrella Additive.

Note: Do not use Resene Wintergrade Additive and Resene Umbrella Additive in the same product. If needed, use one or the other, but not both.

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