4×1″ C24 Treated Timber Rough Sawn (100×22 mm) – 4.8 m
€10.13
In stock
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Product specification
- Length
- 4800 mm
- Width
- 100 mm
- Thickness
- 22 mm
- Material
- Timber
- Wood Type
- Softwood
Treated C24 Timber
4×1 treated whitewood, 100 by 22 mm, is the exposed backing board: soffit and fascia grounds on an open eaves, shed and workshop linings, and shuttering that will be reused outdoors. Strength-graded to C24 and kiln-dried below 22% moisture content before treatment. Lengths run from 3 m to 4.8 m. Stocked in our warehouse for delivery across Ireland.
Why treated C24?
Backing boards on a roof edge sit in the worst combination of conditions: driven rain from outside, and warm damp air venting past them from inside. Untreated timber in that position has a short life and is awkward to replace once the fascia and gutter are on. A treated board removes that as a maintenance item for the life of the roof covering, at very little extra cost per metre.
Installation guidance
Seal cut ends with an end grain preservative before fixing, particularly on a run that will be enclosed behind a fascia where you cannot get back to it. Use stainless fixings on anything that will be permanently wet, and hot dip galvanised elsewhere. Leave a ventilation gap behind a lining board rather than pressing it tight to a wall, so both faces can dry after rain.
Finishing & maintenance
Treatment stops rot and insect attack, not weathering, so a board left fully exposed will still grey. Paint it if it will be seen, once the timber has dried out after treatment. Where the board is dry and internal, the untreated version is the cheaper specification: see 4×1 C24 timber rough sawn. Browse all C24 treated timber sizes, from 3×1 battens up to 9×3 beams. To compare sawn and treated sizes side by side, see our construction timber page.