Hi everyone,

 

I am scratching my head on how best to insulate this steel. I have posted before and think I've tweaked the spec that will work better. It is already installed and is a big cold bridge. The timbers haven't been installed yet, I am thinking of using aerogyl but it is very pricey. Does this sort of spec seem ok? Can I fit the joists through the aerogyl into the timber packing? Spoke to aerogyl supplier and they pretty much advised trying to wrap the steel in aerogyl at every surface where possible.

 

Is there some sort of external insulation panel I can use/render over instead externally?

 

Thanks

At that thickness even the most expensive insulant won't do much; in fact it would be more-or-less decorative as it would be bypassed by the outer skin sitting on top of the beam (and maybe by the patio door). You may be able to build the brickwork off Armatherm (ask them), but if the brick is already in place there's no good solution. Other than to dismantle it it and approach it differently (and claim the cost back from the structural engineer who designed it?)

 

Edited April 1, 20251 yr by Mike

Should have been two beams.

You'll also need a stepped DPC/cavity tray above the beam.

A course of Marmox or at least Thermolite blocks under the inner leaf will help a bit.

i have a beam over my doors similar and yes it bridges out to in. I have insulated board underneath it attached with CT1 and the beam itself packed with PIR and wooden uprights to attach the plasterboard to, used foam along the inner edge to insulate it where i could. Doesnt seem any colder than anything else, happy with it.