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I joists and solid timber studwork

Dave Matthews

Hi Chris

Do you use I joists instead of solid timber studs for price reasons or insulation reason?  Also where do you source these? Or maybe you make them yourself which I can see as a very distinct possibility.


Topic starter Posted : 18/01/2022 5:00 pm
Chris Brookman
Member Admin

Hi Dave

I-joists can be used where U-values are critical but we would always recommend the use of the pre-insulated ones so that you don't have to insulate the web of the joists on site. Alternatively, it can be simpler to use solid timbers as they require no additional insulation and most insulation batts are cut to fit between solid timbers.

We don't supply I-joists but there are several manufacturers including Steico and JJI. I would generally not recommend using the engineered joists with metal webbing in external walls as they are difficult to insulate and are no more effective than solid timber.

Hope that helps.

Posted : 19/01/2022 12:24 pm
Dave Matthews

Hi Chris

Yes helpful. I have found the metal web joists great for pipes/ cables but a massive pain to insulate. I have been talking to steico about their joists. Turns out they have stopped producing the very handy 145x47's which were very handy and only do 220mm which is a bit large. even with all the recent rises in cost the solid timber comes out the same ish price.

Topic starter Posted : 20/01/2022 4:02 pm

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