Application

Maximum m.c. at time of installation for non air-conditioned application

Maximum m.c. at time of installation for air-conditioned application

(kiln-dried timber)

Structural Components

•  columns, beams, bearer, studs ,joists, ties and struts

30%
(Thickness >100 mm)

25%
(Thickness <100 mm)

Not applicable

Not applicable

Roofing

•  rafters, ties, struts, purlins and bracing

•  battens

30%

25%

Not applicable

Not applicable

Staircase

•  stringers, treads, trimmer beam and handrail

•  balustrades

19%

19%

12%

12%

Flooring

•  floor boarding and parquetry

•  skirtings

19%

19%

12%

12%

Walling

•  wall, partition and framing

•  external wall boardings

•  internal wall boardings, slates screens

•  fascia boards

19%

19%

19%

19%

12%

Not applicable

12%

Not applicable

Ceiling Frames

•  cover battens to joints of ceiling sheets

•  ceiling strips and soffit battens

25%

19%

Not applicable

12%

Door & Window Frames

•  door, window and vent frames including their stops and grounds

•  door leaves, window and vent sashes

19%

19%

12%

12%

Furniture

•  built-in fittings, furniture generally

•  workshop furniture

•  science laboratory tops

19%

19%

19%

12%

12%

12%

Beading fillets and edgings generally

19%

12%