Opinions on stormdry/masonry cream

tony3619

Hey, 
Can masonry sealant cream be used as an alternative for missing cavity trays in a cavity wall with a living space underneath?

I've been quoted by a builder to have this done but not sure if it actually stops water penetration during driving rain. 

Regards 

Doozergirl

In a word, no.  Masonry cream is snake oil, it does nothing. Bricks are non porous, that's why houses are made of them.  In 20 years of building and renovating, it has never been mentioned in our business.  It is a solution for nothing.  

What exactly is happening in the house? 

stuart45

Masonry sealer isn't really designed to take the place of cavity trays, although some people try it as a temporary fix.

tony3619

Doozergirl said:

In a word, no.  Masonry cream is snake oil, it does nothing. Bricks are non porous, that's why houses are made of them.  In 20 years of building and renovating, it has never been mentioned in our business.  It is a solution for nothing.  

What exactly is happening in the house? 

Basically I've have some bad leaks in wind driven rain against a cavity wall which have gone into the room below. A builder suggested replacing lead flashing, repointing missing mortar and putting storm dry on the brick work to stop water penetration. There are no weep holes at the base of the wall suggest missing cavity trays. 

tony3619

ite either wind driven rain through the brick , the upstand itself or the gaps near the door. Only happens with wind and rain slamming this wall. Pointing has some holes further up and the top half of the wall does have cavity trays. It's only the bottom half near the flashing they are absent. 

Doozergirl

Where is it coming in inside? 

Grenage

Wind can drive rain up under flashing, but I'd suspect missing mortar first and damaged flashing second.  As Doozer says, don't go getting sealer thrown on the brickwork.

tony3619

Grenage said:

Wind can drive rain up under flashing, but I'd suspect missing mortar first and damaged flashing second.  As Doozer says, don't go getting sealer thrown on the brickwork.

I've tested the flashing and managed to make it leak and as an emergency I have put sealant over the top where it's chased into the brickwork. 

The reason I was thinking brick sealer is every builder that has visited has suggested it's too late to retrofit cavity trays at the bottom, but surely wind driven rain will pass through a single brickwall rather quickly? I don't really wanna use brick sealer but I can't find anyone willing to do cavity trays. Very annoying lol. 

Grenage

I would be looking to sort flashing and pointing before worrying about whether you need a cavity tray.  If you know that water is getting in on the flashing then there's either mortar missing where it goes into the wall, or a crack/tear in the leadwork.  I had the latter in my old place and replaced the damaged section for relatively little (not that lead is cheap).

tony3619

Grenage said:

I would be looking to sort flashing and pointing before worrying about whether you need a cavity tray.  If you know that water is getting in on the flashing then there's either mortar missing where it goes into the wall, or a crack/tear in the leadwork.  I had the latter in my old place and replaced the damaged section for relatively little (not that lead is cheap).

The flashing isn't lead it's a rubber material. The mortar has definitely disappeared. I was thinking maybe leadmate would work better on it that mortar. 

Grenage

Leadmate should be fine.