Cavity Walls, Cavity Trays & Weep Vents - Year?

[KTMsm]

A friend is selling a house which is being condemned by a surveyor for not having weep vents fitted

It was built from 1800 in parts with multiple extensions over the years

Google is confusing me - It states on multiple sites that cavity trays were widely in use in the 1920s

It is then saying that cavity walls were widely used from 1945 - which makes sense

But then how were cavity trays widely in use 25 years earlier ?

I thought weep vents weren't required until much later

[CoolHands]

Can’t he insert some fake ones, that’s what Persimmons etc do

[SteBrown91]

My house was built in 1973 and the original parts have no cavity trays or weep vents.

[Cow Corner]

Cavity walls were introduced gradually from late Victorian times (I once surveyed a building from 1890 that had them, and my own house, circa 1900, has them) and I’d say by about 1925, cavity construction was pretty widespread (though there are of course exceptions).

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

[Promised Land]

CoolHands said:

Can’t he insert some fake ones, that’s what Persimmons etc do

Can you prove that with a link, thanks.

[CoolHands]

Promised Land said:

CoolHands said:

Can’t he insert some fake ones, that’s what Persimmons etc do

Can you prove that with a link, thanks.

I can’t post to TikTok inspector as I’m on my iPad, but yes there are video proofs of weep vents cut in half and embedded in mortar so they look real, but aren’t. You think I lied?

[Chumley.mouse]

Our house was built in 79 no cavity trays or weep vents anywhere

[KTMsm]

Cow Corner said:

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

The issue is that the majority of the house has recently been monocouche rendered

Whilst I'm interested on the general timeline I suppose my real question is when were they manadatory

I started working on building sites in 1990 and I thought they were introduced shortly before that (because the bricklayers moaned and kept forgetting them)

[KTMsm]

Promised Land said:

CoolHands said:

Can’t he insert some fake ones, that’s what Persimmons etc do

Can you prove that with a link, thanks.

It's far from a rare occurrence - mostly depending on the bricklayers and site agent's competence

[CoolHands]

Yes Promised Land comes across as a bit defensive for some reason. Wonder if we’ll hear back from him

[Big Nanas]

Cow Corner said:

Cavity walls were introduced gradually from late Victorian times (I once surveyed a building from 1890 that had them, and my own house, circa 1900, has them) and I’d say by about 1925, cavity construction was pretty widespread (though there are of course exceptions).

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

Interesting. I'm in a 1930's bungalow which doesn't have cavities. Bloody annoying with the condensation it is too.

[Baldchap]

Is it that there are gaps without any covers, or the lack of venting altogether?

If it's the former, rodents can get in so I understand this being highlighted. You can buy cheap packs of vents that just slot into gaps from most appropriate shops.

[Cow Corner]

Big Nanas said:

Cow Corner said:

Cavity walls were introduced gradually from late Victorian times (I once surveyed a building from 1890 that had them, and my own house, circa 1900, has them) and I’d say by about 1925, cavity construction was pretty widespread (though there are of course exceptions).

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

Interesting. I'm in a 1930's bungalow which doesn't have cavities. Bloody annoying with the condensation it is too.

That’s interesting, and in my experience (in London and South East), relatively rare. Though I did once survey a number of post WW1 (homes for heroes type) bungalows, which were of solid wall construction.

It is rare, but some twentieth century houses were cavity built, but with ‘snapped headers’, to emulate a traditional brick bond.

[Mr Pointy]

Promised Land said:

CoolHands said:

Can’t he insert some fake ones, that’s what Persimmons etc do

Can you prove that with a link, thanks.

Lots of examples here:

https://www.youtube.com/@newhomequalitycontrol/vid...

[Cow Corner]

KTMsm said:

Cow Corner said:

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

The issue is that the majority of the house has recently been monocouche rendered

Whilst I'm interested on the general timeline I suppose my real question is when were they manadatory

I started working on building sites in 1990 and I thought they were introduced shortly before that (because the bricklayers moaned and kept forgetting them)

Ah, that complicates things - does he know if weep vents were present before the render was applied and whether the render was applied for decoration, or to attempt to cure an existing ‘damp’ issue?

Off the top of my head, I don’t know when cavity trays were specifically referred go in the approved documents, but I would probably expect to see them present on anything built post 80s.

[Cow Corner]

Also, what did the surveyor actually say - did they just flag that they may be missing, or did they note water ingress likely caused by missing trays?

[Aluminati]

Cow Corner said:

Cavity trays can be retrofitted.

Yes, they can. But it’s a complete ballache, especially if some bight spark has had the cavity filled with polystyrene balls…

[Little Lofty]

I’m not a bricky but from what I remember weep holes only became necessary when cavities started to be filled with insulation, until then any water caught by the cavity tray was diverted down the cavity, obviously when they started to fill cavities with rockwool slabs this was no longer a good idea. Expecting them on a house more than 200 years old is a bit odd, my house was built in 1994 and doesn't have any.

[Cow Corner]

Aluminati said:

Cow Corner said:

Cavity trays can be retrofitted.

Yes, they can. But it’s a complete ballache, especially if some bight spark has had the cavity filled with polystyrene balls…

True, but anyone who does that deserves everything they get

I’ve actually had them fitted to our own house (I’m lucky to have a very good brickie…) and it was tricky but not impossible.

[5s Alive]

Cow Corner said:

KTMsm said:

Cow Corner said:

Cavity trays can be retrofitted, so if they (and the weepholes…) are missing or failed, then it can be overcome.

The issue is that the majority of the house has recently been monocouche rendered

Whilst I'm interested on the general timeline I suppose my real question is when were they manadatory

I started working on building sites in 1990 and I thought they were introduced shortly before that (because the bricklayers moaned and kept forgetting them)

Ah, that complicates things - does he know if weep vents were present before the render was applied and whether the render was applied for decoration, or to attempt to cure an existing ‘damp’ issue?

Off the top of my head, I don’t know when cavity trays were specifically referred go in the approved documents, but I would probably expect to see them present on anything built post 80s.

Absolutely shockin.

I usually avoid his channel because it unleashes my inner Mr Angry.
Grrr...

Oops, meant to quote MrPointy!