Timber Lintol Q

[Rick Hughes]

On my timber frame the standard detailing at window openings was a 3 of 190 x 38 softwood lintols gang nailed together fitted under panel header, and 2

38mm thick 'packers underneath' See pic . (pic is of of 89mm frame not 140mm) was used on windows up to 3m wide. I have a small single storey 'timber frame' outbuilding going up, and while it has to be structurally sound this effective 190 x 140 beam would seem extreme for smaller windows ?

I need to fit in 2 windows that are only 610mm wide . does anybody know what a suitable size wood lintols would be ? (presumably using SC4 ) .. And hoping that I can downsize a bit from 190mm deep.

Is there a span chart ?

[dom]

A definite answer requires load calculations, but 3*38 by 190 does sound excessive for a 610mm beam. OTOH for simplicity of construction it's often easier to stick with the same size throughout. The timber cost is only about =A32/linear metre for 38*190 (i.e. a very common joist size) - but the timber grade could probably be dropped from sc4 (c24 as it is now) to c16 (sc3).