There have been a few discussions which have touched on this. Not sure where though, I'll have a think on it.

I think though that the answer is that you won't get a warranty due to the uncertainty of any existing insulation and its condition. You probably won't get building regs approval either as they will want BBA or similar certification, and I don't think there are any products out there specifically offering this.

How about refilling cavity wall , when a job appears to have been badly done ?
knocking a few hole through here and there on a job has shown CWI to be very patchy and further investigation shows very few drill holes used.
Any thoughts

Indeed, or hot flues crossing the cavity... Not that I know anything.

Rgds

Damon

Few thoughts:

1.
Look at p34 and p35 of Approved doc C which deals with damp ingress by geography:
http://www.planningportal.gov.uk/buildingregulations/approveddocuments/partc/documentc
If this says full fill is a no go because of driving rain then there is probably a good reason for the cavity.

2.
If not then other than cables in the cavity I think that you're intro burocratic technicalities (CWI installers are used to dealing with flues etc.). An anonymous chat with your local BCO to find what his thoughts are is worth a punt. Platinum beads should bring you up to building regs and normal might depending on your construction so he might be willing to sign off?

3.
Either way on point 2 I'd imagine that the guarantee and the subsidy eligibility criteria would be the sticking points. If you speak to polybead installers and are clear that you don't need a guarantee and will pay the unsubsidised price you might get lucky... You should be able to determine this over the phone if you can speak to the surveyor them-self. You might also find one of the smaller CWI companies is willing to cut you more slack.

4.
As a last shot there is the polyurethane injection guys who I don't think have a BBA cert although mixing polymeric insulation types is probably a bad idea.

Hope this helps

J