How much does a 45 × 95 mm × 2.4 m length of timber weigh?

45 × 95 mm is one of the common regularised framing sizes in the UK (CLS studs are a slightly smaller 38 × 89 mm). Norway spruce “whitewood” is noticeably lighter than Scots pine “redwood” — switch the species to compare — and freshly treated timber can be much heavier.

What to know about the weight of 45 × 95 mm timber

Regularised timber is machined to a consistent size, so 45 × 95 mm is the real cross-section rather than a trade name — unlike a North American 2×4, which is called 2 × 4 in but measures 1½ × 3½ in (the US version is How much does a 2x4x8 weigh).

• Redwood or whitewood? Merchants sell Scots pine as “redwood” and Norway spruce as “whitewood”. At typical densities of 550 and 405 kg/m³, the same 2.4 m length weighs 5.64 kg or 4.16 kg, so check which one the delivery note says.
• Longer lengths. A 4.8 m length of this section is about 11.3 kg, and a 47 × 150 mm joist at 4.8 m about 18.6 kg — fine for one person on the ground, awkward up a ladder.
• Dry graded, treated and wet. Structural timber stamped DRY GRADED was graded at around 20% moisture or less, so it can weigh a little more than this 12% estimate. Freshly pressure-treated (tanalised) timber is often still wet and noticeably heavier.
• A pack for a stud wall. Twenty 2.4 m lengths come to about 113 kg of Scots pine — more than many car roof bars are rated for, so plan a delivery or a van.

Sheathing the same wall? How much does a sheet of 3/4 plywood weigh includes an 18 mm sheet, and the calculator’s sheet mode handles 1220 × 2440 mm boards from 6 to 18 mm.