Roof Space Interior Spray

[koiman]

Our loft is a mess, the cement that holds the 1930's tiles in place is very dusty and drops over any thing stored up there. I'm told you can buy a glue type spray that seals it and stops it dropping. Does anyone know where I can purchase the stuff or who makes it ?

[The Builder]

I guess you have slates rather than tiles Koiman?

No matter though. It's an old, outmoded technique known as "back-pointing".
Any Builders' Merchants or DIY store will sell large aerosol cans of polyurethane foam. Simple job to spray over the pointing. Rather a tedious, time-consuming job though.

A little easier... would be to knock up a mix of PVA adhesive diluted with water........ approx 1 PVA to 5 water.

This mix is a little too viscous to spray with a conventional garden/preservative type spray. You may get away with it, but there'll be a lot of clogging in the nozzle.

It would be well worth renting an airless spray from a hire centre. The sort of thing that sprays paint would do it.

Spray onto the pointing, and it'll re-solidify the bulk of the mortar and its surface dust.

[koiman]

Thank you I'll give the pva a go.