Tape and foam Kingspan if using Multifoil

[fiver381]

Hi I'm insulating my loft conversion and have so far used 100mm kingspan between the rafters.

Am proposing to follow this with TLX Silver, 38mm battens and 12.5mm plasterboard.

My question is the TLX Silver will create a vapour barrier so do I also need to foam fill all the Kingspan gaps and tape all the joints between sheets? Or is this done for another reason?

Thanks

 

[SurreyRoofingEstimator]

Just tape the joints of the TLX-Silver, that should be fine. Taping the joints in the rigid insulation won't do anything apart from give you a headache

 

[fiver381]

That's exactly what I was hoping you'd say. Thanks